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  • 201.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Chen, Si
    Chalmers, Dept Microtechnol & Nanosci MC2, SE-41296 Gothenburg, Sweden..
    Huo, Jinxing
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Gamstedt, Erik Kristofer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik.
    Liu, Johan
    Chalmers, Dept Microtechnol & Nanosci MC2, SE-41296 Gothenburg, Sweden..
    Zhang, Shi-Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Zhang, Zhi-Bin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Mechanically Stretchable and Electrically Insulating Thermal Elastomer Composite by Liquid Alloy Droplet Embedment2015Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, artikel-id 18257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Stretchable electronics and soft robotics have shown unsurpassed features, inheriting remarkable functions from stretchable and soft materials. Electrically conductive and mechanically stretchable materials based on composites have been widely studied for stretchable electronics as electrical conductors using various combinations of materials. However, thermally tunable and stretchable materials, which have high potential in soft and stretchable thermal devices as interface or packaging materials, have not been sufficiently studied. Here, a mechanically stretchable and electrically insulating thermal elastomer composite is demonstrated, which can be easily processed for device fabrication. A liquid alloy is embedded as liquid droplet fillers in an elastomer matrix to achieve softness and stretchability. This new elastomer composite is expected useful to enhance thermal response or efficiency of soft and stretchable thermal devices or systems. The thermal elastomer composites demonstrate advantages such as thermal interface and packaging layers with thermal shrink films in transient and steady-state cases and a stretchable temperature sensor.

  • 202.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Chen, Si
    Chalmers University of Technology.
    Huo, Jinxing
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik.
    Gravier, Laurent
    University of Applied Sciences and Arts Western Switzerland.
    Gamstedt, Erik Kristofer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik.
    Liu, Johan
    Chalmers University of Technology.
    Zhang, Shi-Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Zhang, Zhi-Bin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan, Peoples R China.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thermal Elastomer Composites for Soft Transducers2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    There is a need for thermal elastomer composites (TEC) which are stretchable, electrically insulating and easily processablefor soft and stretchable sensor or actuator systems as a thermal conductor or heat spreader at an interface or in a package.A novel TEC was made by embedding a gallium based liquid alloy (Galinstan) as a droplet in polydimethylsiloxane (PDMS,Elastosil RT 601) matrix with a high speed mechanical mixing process.

  • 203.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Cruz, Javier
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Chen, Si
    Chalmers, Dept Microtechnol & Nanosci MC2, Kemivagen 9, SE-41296 Gothenburg, Sweden.
    Gravier, Laurent
    Univ Appl Sci & Arts Western Switzerland, Inst Micro & Nano Tech, CH-1401 Yverdon, Switzerland.
    Liu, Johan
    Chalmers, Dept Microtechnol & Nanosci MC2, Kemivagen 9, SE-41296 Gothenburg, Sweden.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Zhang, Shi-Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Zhang, Zhi-Bin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Stretchable thermoelectric generators metallized with liquid alloy2017Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 9, nr 18, s. 15791-15797Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conventional thermoelectric generators (TEGs) are normally hard, rigid, and flat. However, most objects have curvy surfaces, which require soft and even stretchable TEGs for maximizing efficiency of thermal energy harvesting. Here, soft and stretchable TEGs using conventional rigid Bi2Te3 pellets metallized with a liquid alloy is reported. The fabrication is implemented by means of a tailored layer-by-layer fabrication process. The STEGs exhibit an output power density of 40.6 mu W/cm(2) at room temperature. The STEGs are operational after being mechanically stretched-and-released more than 1000 times, thanks to the compliant contact between the liquid alloy interconnects and the rigid pellets. The demonstrated interconnect scheme will provide a new route to the development of soft and stretchable energy-harvesting avenues for a variety of emerging electronic applications.

  • 204.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Cruz, Javier
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Zhang, Zhibin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Zhang, Shi-Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Soft Bendable Thermoelectric Generator for Uneven Surface Implementation2015Ingår i: 26th Micromechanics and Microsystems Europe Workshop, 2015, s. A8-Konferensbidrag (Övrigt vetenskapligt)
  • 205.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hagman, Anton
    KTH, Hållfasthetslära, Stockholm.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Jobs, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Liquid alloy printing of microfluidic stretchable electronics2012Ingår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 22, nr 12, s. 4657-4664Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recently, microfluidic stretchable electronics has attracted great interest from academia since conductive liquids allow for larger cross-sections when stretched and hence low resistance at longer lengths. However, as a serial process it has suffered from low throughput, and a parallel processing technology is needed for more complex systems and production at low costs. In this work, we demonstrate such a technology to implement microfluidic electronics by stencil printing of a liquid alloy onto a semi-cured polydimethylsiloxane (PDMS) substrate, assembly of rigid active components, encapsulation by pouring uncured PDMS on-top and subsequent curing. The printing showed resolution of 200 mm and linear resistance increase of the liquid conductors when elongated up to 60%. No significant change of resistance was shown for a circuit with one LED after 1000 times of cycling between a 0% and an elongation of 60% every 2 s. A radio frequency identity (RFID) tag was demonstrated using the developed technology, showing that good performance could be maintained well into the radio frequency (RF) range.

  • 206.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A fast liquid alloy patterning technique for microfluidic stretchable electronics2014Ingår i: A fast liquid alloy patterning technique for microfluidic stretchable electronics, 2014, s. 48-50Konferensbidrag (Refereegranskat)
    Abstract [en]

    By tape-transferring cut patterns in vinyl onto a PDMS substrate and then using it as stencil masks, liquid alloy is printed with arbitrary patterns onto the substrate for stretchable electronics. This brings new possibilities in printing patterns such as loop and ring structures, which are impossible to achieve with a conventional metal stencil that will lose the isolated parts.

  • 207.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Adhesive transfer soft lithography: low-cost and flexible rapid prototyping of microfluidic devices, Micro and Nanosystems2014Ingår i: micro and nanosystems, ISSN 1876-4037, Vol. 6, s. 42-49Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A simple and low-cost approach was proposed for prototyping PDMS based microfluidic devices by transferringadhesive film microstructures onto a flexible substrate as a mould for PDMS replicas. The microstructures were engravedon an adhesive coated film using a commercial cutting plotter and then transferred (or laminated) onto a flexiblesubstrate, allowing for engraved isolated patterns. The proposed technique was demonstrated by a hydrodynamic focusingmicrofluidic device, having splitting and re-combining sheath channels. The whole processing could be finished within 1h in a normal laboratory environment. This approach offers an easy, flexible and rapid prototyping of microfluidic andlab-on-a-chip devices to users without expertise in microfabrication. In addition, by minimizing the use of chemicals, theprocess becomes more environmentally friendly than conventional photolithography based micro-fabrication techniques.

  • 208.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Atomization Patterning and Multifunctional Elastomer Engineeringfor Liquid Alloy Applied Compliant Microsystems2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Unique and beneficial gallium based liquid alloys [1,2] have high potential to a compliant sensor,power source and wireless communication unit. There are several types of patterning techniques forliquid alloys have been reported such as injection [3], printing [4], selective wetting [5], stamping [6]and direct writing [7]. Our recently developed liquid alloy printing technique employing atomizationand tape transfer masking for batch type and large area fabrication is practically useful for micrometerscale conductor patterning to realize a compliant microsystem. The process provides a quick and easyfabrication scheme for soft and stretchable, liquid alloy applied microsystems.On the other hand, an elastomer as a packaging material has an important role in compliantmicrosystem performance. Polydimethylsiloxane (PDMS) based elastomer and silicone have beenwidely used due to their good processability with soft-lithography and versatile behaviors such asstretchability, inertness and transparency for microfluidics, soft robotics and stretchable electronics.Still, the PDMS based elastomer needs to be tuned in many properties, in order to meet requirementsof applications. Mechanical properties tuning of the PDMS based elastomers have been reported withdifferent approaches [10,11,12] to make more compliant and stretchable one. Here, we present ourrecently developed multi-functional elastomers, which are based on PDMS. One is a thermalelastomer composite (TEC) and the other is a soft, stretchable and sticky PDMS based elastomer(S3-PDMS). The former is useful for stretchable thermal systems such as a temperature sensor or athermoelectric generator to achieve higher sensitivity and higher efficiency. Nanometer scale liquidalloy droplet fillers to tune the elastomer to be softer or stiffer can be dispersed in the PDMS basedelastomer by high speed mixing. The thermal conductivity reaches twelve fold higher than the originalelastomer with keeping 100% stretchability. The latter is useful for skin applicable devices, whichdemands lower compliance than skin modulus, high stretchability and self-adhesive surface toreusable attach on human skin. Ethoxylated polyethylenimine (PEIE) enables the PDMS basedelastomer more compliant and stretchable with a simple one step mixing process. Less than a 0.1 wt%additive in PDMS prepolymer makes it sticky as well by heterogeneous crosslinking domainsincluding loosely crosslinked parts. The elastic modulus reaches 24 kPa and the elongation at break isover 300%. The adhesion force is more than 10 times of the original one. Both of tuning processes aretunable with the mixing conditions with additives in one step processing.Several compliant microsystems have been successfully fabricated with the developed patterningtechniques of the liquid alloy, and operated under dynamic conditions. A stretchable strain sensor,stretchable wireless power transfer coil, stretchable radio frequency identification (RFID, 13.56 MHz)tag and stretchable thermoelectric generator are made of liquid alloy patterns and multi-functionalelastomers, which is tuned with liquid alloy fillers and heterogeneous crosslink structures.

    [1] M. D. Dickey, R. C. Chiechi, R. J. Larsen, E. A. Weiss, D. A. Weitz and G. M. Whitesides,“Eutectic Gallium-Indium (EGaIn): A Liquid Metal Alloy for the Formation of Stable Structuresin Microchannels at Room Temperature,” Adv. Funct. Mater. 2008, 18, 1097-1104.[2] T. Liu, P. Sen and C. J. Kim, ”Characterization of liquid-metal Galinstan® for dropletapplications,” in Micro Electro Mechanical Systems (MEMS), 2010 IEEE 23rd InternationalConference on. pp. 560-563, Wanchai, Hong Kong, 24-28 Jan. 2010.

    [3] Y. L. Park, B. R. Chen and R. J. Wood,“Design and Fabrication of Soft ArtificialSkin Using Embedded Microchannels andLiquid Conductors,” IEEE Sens. J. 2012, 12,2711.[4] S. H. Jeong, A. Hagman, K. Hjort, M. Jobs,J. Sundqvist and Z. Wu, “Liquid alloyprinting of microfluidic stretchableelectronics,” Lab Chip 2012, 12, 4657.[5] R. K. Kramer, C. Majidi and R. J. Wood,“Masked Deposition of Gallium-IndiumAlloys for Liquid-Embedded ElastomerConductors,” Adv. Funct. Mater. 2013, 23,5292.[6] A. Tabatabai, A. Fassler, C. Usiak and C.Majidi, “Liquid-phase gallium-indium alloyelectronics with microcontact printing,”Langmuir 2013, 29, 6194.[7] J. T. Muth, D. M. Vogt, R. L. Truby, Y.Menguc, D. B. Kolesky, R. J. Wood and J.A. Lewis, “Embedded 3D printing of strainsensors within highly stretchableelastomers,” Adv. Mater. 2014, 26, 6307.[8] I. D. Johnston, D. K. McCluskey, C. K. L.Tan and M. C. Tracey, “Mechanicalcharacterization of bulk Sylgard 184 formicrofluidics and microengineering,” J.Micromech. Microeng. 2014, 24, 035017.[9] L. H. Cai, T. E. Kodger, R. E. Guerra, A. F.Pegoraro, M. Rubinstein and D. A. Weitz,“Soft Poly(dimethylsiloxane) Elastomersfrom Architecture-Driven EntanglementFree Design,” Adv. Mater. 2015, 27, 5132.

  • 209.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Tape transfer atomization patterning of liquid alloys for microfluidic stretchable wireless power transfer2015Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, s. 8419-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Stretchable electronics offers unsurpassed mechanical compliance on complex or soft surfaces like the human skin and organs. To fully exploit this great advantage, an autonomous system with a self-powered energy source has been sought for. Here, we present a new technology to pattern liquid alloys on soft substrates, targeting at fabrication of a hybrid-integrated power source in microfluidic stretchable electronics. By atomized spraying of a liquid alloy onto a soft surface with a tape transferred adhesive mask, a universal fabrication process is provided for high quality patterns of liquid conductors in a meter scale. With the developed multilayer fabrication technique, a microfluidic stretchable wireless power transfer device with an integrated LED was demonstrated, which could survive cycling between 0% and 25% strain over 1,000 times.

  • 210.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Tape Transfer Printing of a Liquid Metal Alloy for Stretchable RF Electronics2014Ingår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, nr 9, s. 16311-16321Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In order to make conductors with large cross sections for low impedance radio frequency (RF) electronics, while still retaining high stretchability, liquid-alloy-based microfluidic stretchable electronics offers stretchable electronic systems the unique opportunity to combine various sensors on our bodies or organs with high-quality wireless communication with the external world (devices/systems), without sacrificing enhanced user comfort. This microfluidic approach, based on printed circuit board technology, allows large area processing of large cross section conductors and robust contacts, which can handle a lot of stretching between the embedded rigid active components and the surrounding system. Although it provides such benefits, further development is needed to realize its potential as a high throughput, cost-effective process technology. In this paper, tape transfer printing is proposed to supply a rapid prototyping batch process at low cost, albeit at a low resolution of 150 mu m. In particular, isolated patterns can be obtained in a simple one-step process. Finally, a stretchable radio frequency identification (RFID) tag is demonstrated. The measured results show the robustness of the hybrid integrated system when the tag is stretched at 50% for 3000 cycles.

  • 211.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nilsson, Frida
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Huazhong University of Science and Technology.
    Sahlberg, Arne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Berglund, Albin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    High Resolution Patterning of Liquid Alloy with Stretch Shrink Printing for a High Density Array of Small, Stretchable Strain Sensors2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    A liquid alloy allows large strain due to its liquid state in a stretchable and deformable system and thus,a resistive strain sensor made of liquid alloy can measure large strain of human motion. Liquid alloy-based strainsensors have been demonstrated with various designs for a better understanding of human motion dynamics and toimprove the design of wearable robotics. So far, the sensors have a large size of several centimeters.To expand the applicability of liquid alloy-based strain sensors, a high resolution patterning technique would enable asmall size and high density of the strain sensor. This allows strain measurements in area-limited situations ordirectional strain measurement with high density arrays. A small-size, high-density stretchable strain sensor array canbenefit many DOF (degree of freedom) dynamics measurements on, e.g., a shoulder, hand, foot, or neck.For realizing a highly stretchable strain sensor, a novel soft, highly stretchable and sticky elastomer was used toencapsulate the liquid alloy. A quick and simple patterning technique for high density design has been developed. Thiscombined our previously developed spray printing technique of the liquid alloy with a stretched elastomer substrateand encapsulation of it. The substrate could be stretched either one dimensionally or radially, depending on thedesign.High resolution patterns that were radially stretched and uniformly shrunken on an elastomer substrate weresuccessfully achieved with the stretch-shrink-printing technique. This technique enables large area fabrication withone step processing. High density patterns that have a low resistance and large stretchability were realized with theliquid alloy for a small and highly stretchable strain sensor. A high density array of small strain sensors wasdemonstrated in measuring strains in different directions of neck movements of the human body.

  • 212.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Shou, Zhang
    Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
    PDMS-Based Elastomer Tuned Soft, Stretchable, and Sticky for epidermal electronics2016Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, nr 28, s. 5830-5836Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Targeting good user experiences, softness and stretchability are essential features for epidermal devices in body signal monitoring and body area stimulation. A highly soft, stretchable and sticky polydimethylsiloxane based elastomer (S3-PDMS) is achieved by a simple process with a widely used siloxane precursors, the properties of which are tuned by adding small fractions of an amine-based polymer, ethoxylated polyethylenimine (EPEI). This allows formation of a thick unobstrusive patch and may ease implementation of epidermal electronics in wearable healthcare applications. 

  • 213.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala University.
    Shou, ZhangHuazhong University of Science and Technology.Hjort, KlasUppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.Wu, ZhigangUppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sticky elstomer composites for microfluidic stretchable sensor patches2015Proceedings (redaktörskap) (Refereegranskat)
    Abstract [en]

    Epidermal electronics and soft robotics are harnessing the advantages of the adaptable and compliantsoft contacts of soft materials. Soft materials can conformally match the morphology of the contact surfaces, which isthe vital point in the implementation of epidermal sensors or soft actuators (S. Xu et al., Soft Microfluidic Assemblies ofSensors, Circuits, and Radios for the Skin, Science, 2014, 344, 70-74). Unfortunately, this conformality can suffer fromdelamination or air trapping at the interface during contact movement. Here, adhesion of soft material surfaces is thecritical parameter. For example, an epidermal sensor on human internal organs and skin, or soft-robotic fingers forgrabbing or climbing needs proper adhesion to its targeted contact surface. Mechanical softness of elastomermaterials provides a good ensemble with surface adhesion because the conformal contact of the soft materials assiststhe adhesion on the target surfaces. Alas, when the soft device is thicker, with its inherent adhesion its compliancemay not suffice but an adhesive layer is needed to ensure good contact.Sticky surfaces of soft materials will significantly help to improve adhesion on target surfaces by preventing sliding.Therefore, more reliable immobilization and manipulation of contacted objects can be secured. Physical and chemicaladhesion forces of the soft material surfaces can be utilized for this purpose. We have developed a sticky elastomercomposite based on PDMS, which has a tape-like adhesive surface after curing. This sticky elastomer composite isstretchable and compliant. The processability of it is compatible with PDMS processes for microfluidic stretchabledevices. It can be easily shaped with laminating, spinning and casting before curing. And, it is reusable several timeswithout leaving residues on the adhered surfaces after detaching and its adhesive strength is tunable with differentmixing ratios with the additive.The sticky elastomer composite showed high enough adhesion to secure attachment on human skin and to lift smallobjects with different surface roughness. Here, soft fingers lifting masses which have different surface morphologieswere tested to verify the compatibility of adhesion force on various surface conditions for soft-robotic manipulationapplication. To show the easy and robust implementation, the sticky elastomer composite is demonstrated with astretchable sensor patch that can be secured to human skin, using much of our recently developed pamphlet ofprocessing technologies (Z.G. Wu, K. Hjort, S.H. Jeong, Microfluidic Stretchable Radio Frequency Devices,Proceedings of the IEEE, 2015, 99, 1-15). Such sensor patches may be suitable as wireless sensor nodes inepidermal body area networks for fitness and healthcare monitoring.

  • 214.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huazhong Univ Sci & Technol, State Key Lab Digital Equipment & Mfg, Wuhan, Peoples R China.
    Stretchable wireless power transfer with a liquid alloy coil2015Ingår i: Micro Electro Mechanical Systems (MEMS), 2015 28th IEEE International Conference on, 2015, s. 1137-1140Konferensbidrag (Refereegranskat)
    Abstract [en]

    An integrated stretchable wireless power transfer device was demonstrated by packaging rigid electronic chips onto a liquid alloy coil patterned on a half-cured polydimethylsiloxane (PDMS) surface. To obtain low enough resistance, the long liquid alloy coil with a large cross section was made with a tape transfer masking followed by spray deposition of the liquid alloy. The measured results indicated the wireless power transfer efficiency reached 10% at 140 kHz and good performance under 25% overall strain. Different sizes of liquid alloy coils and a soft magnetic composite core were tested to improve the efficiency of the system.

  • 215.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Batch produced microfluidic stretchable printed circuits for wireless systems2014Ingår i: Batch produced microfluidic stretchable printed circuits for wireless systems, 2014, s. 27-30Konferensbidrag (Refereegranskat)
    Abstract [en]

    The liquid alloy which is Ga-In-Sn based alloy is the most promising stretchable conductor material for soft electronics. Patterning ofliquid alloys will be the key processing step to fabricate devices and we have here applied a screen printing technique withtape transfer masking to enable batch processing for a large areas at low cost. The elastomer surface should be controlled forthe printing and encapsulation of liquid alloys. Liquid-alloy-based RF electronics shows potential in interfacing man to machinein applications such as body area network or soft robotics.

  • 216.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huangzhou University of Science and Technology, Wuhan, China.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Plåster med sträckbara trådlösa givare för medicinsk teknik2015Ingår i: Abstracts Medicinteknikdagarna 2015 / [ed] Fredrik Nikolajeff, 2015, s. 59-Konferensbidrag (Refereegranskat)
    Abstract [sv]

    Målet med denna presentation är att visa på olika möjligheter för sträckbara trådlösa givare för medicinsk teknik. Vi söker läkare och företag som är intresserade av detta.

    Elektronikbranschen förutspår en massiv ökning av trådlösa sensorsystem inom en snar framtid och ett ”Sakernas Internet”. En av de stora utvecklingsområdena här är  bärbara tillbehör; trådlösa sensornoder i kroppsnära nätverk som kommunicerar med en smartphone. Men det finns en generation efter detta och många förutspår att det kommer att vara nätverk med trådlösa givare och kommunikationsnoder som är i direktkontakt med kroppen, på huden eller som implantat. Det är här töjbar elektronik kommer att sätta sin prägel då dess mjuka, följsamma och sträckbara folier med givare och elektronik erbjuder en oöverträffad mekanisk koppling till vår hud och våra organ.

    Den mest uppmärksammade tekniken är den s.k. elastiska elektroniken, vilken utgår från ultratunna, och därmed flexibla, integrerade kretsar som överförs till elastiska substrat. Det möjliggör väldigt tunna system som kan ha samma höga upplösning och täthet av komponenter som annan mikroelektronik1. Detta passar väl till mindre strukturer men har flera svagheter vid tillverkning av system där större och tjockare komponenter krävs. Här har vi i stället utvecklat sträckbara kretskort med en flytande metall som ledare och kontakter. De främsta fördelarna med flytande ledare är att en vätska följer med alla formändringar utan motstånd och att små styva komponenter kan modulärt monteras och kontakteras till ledaren utan att kontakter bryts när den utsätts för en större töjning – istället kommer komponentens kontakt att glida på vätskan2. Vi har redan visat att vi idag kan producera avancerade kretsar med flera lager av ledare och monterade små komponenter för olika trådlösa system med töjningsgivare, RFID, trådlös energiöverföring, termoelektriska komponenter, mm.

    I denna presentation visar vi hur kan tillverka intelligenta och trådlösa sträckbara plåster med olika givare för att läsa av värmeflödet från en kropp. Vi tror dock att det är lätt för oss att göra andra typer av givare eller montera små chip av kommersiella givare och transdermala elektroder för andra medicinska tillämpningar. Vi behöver dock samverka med läkare och medicinsktekniska företag för att välja och pröva de bäst lämpade givarna.

  • 217.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Soft, Stretchable and Sticky PDMS2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    A tunable process of polydimethylsiloxane (PDMS) has been created with a tiny amount of a polyethylenimine, ethoxylated (PEIE) solution. With varying the PEIE fraction, the softness, stretchablility and stickiness of a commercial PDMS (Sylgard®184) are enhanced at the same time. We controlled the curing process of the tuned PDMS to achieve desired mechanical properties. A soft strain sensor for finger movement monitoring is successfully demonstrated with a liquid alloy resistor in the soft, stretchable and sticky (S3-PDMS) packaging.

  • 218.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Zhang, S.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sticky elastomer composite for microfluidic stretchable sensor patches2015Ingår i: 2015 MRS Fall Meeting, 2015, s. B12.04-Konferensbidrag (Övrigt vetenskapligt)
  • 219.
    Jiao, Mingzhi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Microfabricated Gas Sensors Based on Hydrothermally Grown 1-D ZnO Nanostructures2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis, gas sensors based on on-chip hydrothermally grown 1-D zinc oxide (ZnO) nanostructures are presented, to improve the sensitivity, selectivity, and stability of the gas sensors.

    Metal-oxide-semiconductor (MOS) gas sensors are well-established tools for the monitoring of air quality indoors and outdoors. In recent years, the use of 1-D metal oxide nanostructures for sensing toxic gases, such as nitrogen dioxide, ammonia, and hydrogen, has gained significant attention. However, low-dimensional nanorod (NR) gas sensors can be enhanced further. Most works synthesize the NRs first and then transfer them onto electrodes to produce gas sensors, thereby resulting in large batch-to-batch difference.

    Therefore, in this thesis six studies on 1-D ZnO NR gas sensors were carried out. First, ultrathin secondary ZnO nanowires (NWs) were successfully grown on a silicon substrate. Second, an on-chip hydrothermally grown ZnO NR gas sensor was developed on a glass substrate. Its performance with regard to sensing nitrogen dioxide and three reductive gases, namely, ethanol, hydrogen, and ammonia, was tested. Third, three 1-D ZnO nanostructures, namely, ZnO NRs, dense ZnO NWs, and sparse ZnO NWs, were synthesized and tested toward nitrogen dioxide. Fourth, hydrothermally grown ZnO NRs, chemical vapor deposited ZnO NWs, and thermal deposited ZnO nanoparticles (NPs) were tested toward ethanol. Fifth, the effect of annealing on the sensitivity and stability of ZnO NR gas sensors was examined. Sixth, ZnO NRs were decorated with palladium oxide NPs and tested toward hydrogen at high temperature.

    The following conclusions can be drawn from the work in this thesis: 1) ZnO NWs can be obtained by using a precursor at low concentration, temperature of 90 °C, and long reaction time. 2) ZnO NR gas sensors have better selectivity to nitrogen dioxide compared with ethanol, ammonia, and hydrogen. 3) Sparse ZnO NWs are highly sensitive to nitrogen dioxide compared with dense ZnO NWs and ZnO NRs. 4) ZnO NPs have the highest sensitivity to ethanol compared with dense ZnO NWs and ZnO NRs. The sensitivity of the NPs is due to their small grain sizes and large surface areas. 5) ZnO NRs annealed at 600 °C have lower sensitivity toward nitrogen dioxide but higher long-term stability compared with those annealed at 400 °C. 6) When decorated with palladium oxide, both materials form alloy at a temperature higher than 350 °C and decrease the amount of ZnO, which is the sensing material toward hydrogen. Thus, controlling the amount of palladium oxide on ZnO NRs is necessary.

    Delarbeten
    1. Controlled Synthesis and Understanding of GrowthMechanism: Parameters for Atmospheric PressureHydrothermal Synthesis of Ultrathin SecondaryZnO Nanowires
    Öppna denna publikation i ny flik eller fönster >>Controlled Synthesis and Understanding of GrowthMechanism: Parameters for Atmospheric PressureHydrothermal Synthesis of Ultrathin SecondaryZnO Nanowires
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    2016 (Engelska)Ingår i: Journal of Scientific Research and Reports, ISSN 2320-0227, E-ISSN 2320-0227, Vol. 9, nr 5, s. 1-10Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Synthesis of ultrathin ZnO nanowires gains great attention from research community because oftheir large potential in applications involving optoelectronics and sensors. In this study, a lowpressure and low-temperature hydrothermal synthesis of ultrathin ZnO nanowires is studied tounderstand the growth mechanisms better. To achieve this aim, an about 10 nm thin Zn seed layerwas sputter-deposited on a silicon (100) wafer for the hydrothermal growth of ZnO nanowires in anequimolar aqueous solution of Zn(NO3)2 and hexamethylenetetramine. X-ray diffraction analysis confirmed that the Zn layer was self-oxidized into ZnO in air soon after deposition and thenfunctioned as the seed for the preferred growth of c-oriented ZnO nanorods. Different growthconditions were investigated to identify how concentration, temperature, and time influence the finalmorphology of the synthesized ZnO nanostructures. It was found that under the atmosphericpressure, concentration and temperature have to be higher than 0.0025 M and 50°C, respectively,for the ZnO nanorods to nucleate and grow densely. Low concentration gives sparse and randomlyoriented nanorods, whereas high concentration gives dense and vertical nanorods. Ultrathin ZnOsecondary nanowires with an average diameter of less than 20 nm were successfully synthesizedin a solution with concentration of 0.005 M at 90°C for about 16 h. By analyzing the scanningelectron microscopy images of the ZnO nanostructures obtained at different growth conditions, amechanism is proposed for the growth of the ultrathin secondary ZnO nanowires. This findingprovides a cost-effective and straightforward pathway to prepare ultrathin ZnO nanowires.

    Nyckelord
    ZnO nanowires, growth parameters, growth mechanism
    Nationell ämneskategori
    Nanoteknik
    Identifikatorer
    urn:nbn:se:uu:diva-286795 (URN)
    Tillgänglig från: 2016-04-21 Skapad: 2016-04-21 Senast uppdaterad: 2017-11-30Bibliografiskt granskad
    2. On-chip hydrothermal growth of ZnO nanorods at low temperature for highly selective NO2 gas sensor
    Öppna denna publikation i ny flik eller fönster >>On-chip hydrothermal growth of ZnO nanorods at low temperature for highly selective NO2 gas sensor
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    2016 (Engelska)Ingår i: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 169, s. 231-235Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    ZnO nanorods were selectively grown on-chip with a two-step low-temperature hydrothermal method and their gas sensing properties were investigated. Small zinc islands were deposited by sputtering on a glass substrate and used as nucleation sites for the ZnO nanorod growth. An equimolar aqueous solution of 0.005 M Zn(NO3)(2)center dot 6H(2)O and (CH2)(6)N-4 at 85 center dot C was used in two steps. The first step was used for nucleation and growth of short ZnO nanorods for 4 h, whereas the second step was used for elongation of the nanorods for 36 h. Long porous nanorods from neighboring islands connected to each other and formed nanorod junctions. A gas sensor with such nanorods was evaluated towards NO2, ethanol, hydrogen, and ammonia to characterize its sensing properties. It showed that the gas sensor has the highest sensitivity to NO2, and a very high selectivity to this gas when measured at 450 degrees C.

    Nyckelord
    Crystal growth, Deposition, Nanocrystalline materials, Sensors, Thin films
    Nationell ämneskategori
    Materialteknik
    Identifikatorer
    urn:nbn:se:uu:diva-281470 (URN)10.1016/j.matlet.2016.01.123 (DOI)000370533300058 ()
    Tillgänglig från: 2016-03-24 Skapad: 2016-03-24 Senast uppdaterad: 2017-08-10
    3. Comparison of NO2 Gas-Sensing Properties of Three Different ZnO Nanostructures Synthesized by On-Chip Low-Temperature Hydrothermal Growth
    Öppna denna publikation i ny flik eller fönster >>Comparison of NO2 Gas-Sensing Properties of Three Different ZnO Nanostructures Synthesized by On-Chip Low-Temperature Hydrothermal Growth
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    2018 (Engelska)Ingår i: Journal of Electronic Materials, ISSN 0361-5235, E-ISSN 1543-186X, Vol. 47, nr 1, s. 785-793Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Three different ZnO nanostructures, dense nanorods, dense nanowires, and sparse nanowires, were synthesized between Pt electrodes by on-chip hydrothermal growth at 90°C and below. The three nanostructures were characterized by scanning electron microscopy and x-ray diffraction to identify their morphologies and crystal structures. The three ZnO nanostructures were confirmed to have the same crystal type, but their dimensions and densities differed. The NO2 gas-sensing performance of the three ZnO nanostructures was investigated at different operation temperatures. ZnO nanorods had the lowest response to NO2 along with the longest response/recovery time, whereas sparse ZnO nanowires had the highest response to NO2 and the shortest response/recovery time. Sparse ZnO nanowires also performed best at 300°C and still work well and fast at 200°C. The current–voltage curves of the three ZnO nanostructures were obtained at various temperatures, and the results clearly showed that sparse ZnO nanowires did not have the linear characteristics of the others. Analysis of this phenomenon in connection with the highly sensitive behavior of sparse ZnO nanowires is also presented.

    Nationell ämneskategori
    Annan materialteknik
    Identifikatorer
    urn:nbn:se:uu:diva-320153 (URN)10.1007/s11664-017-5829-6 (DOI)000418580800093 ()
    Tillgänglig från: 2017-04-16 Skapad: 2017-04-16 Senast uppdaterad: 2018-01-29Bibliografiskt granskad
    4. Ethanol-Sensing Characteristics of Nanostructured ZnO: Nanorods, Nanowires, and Porous Nanoparticles
    Öppna denna publikation i ny flik eller fönster >>Ethanol-Sensing Characteristics of Nanostructured ZnO: Nanorods, Nanowires, and Porous Nanoparticles
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    2017 (Engelska)Ingår i: Journal of Electronic Materials, ISSN 0361-5235, E-ISSN 1543-186X, Vol. 46, nr 6, s. 3406-3411Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The morphology and crystalline size of metal oxide-sensing materials arebelieved to have a strong influence on the performance of gas sensors. In thispaper, we report a comparative study on the ethanol-sensing characteristics ofZnO nanorods, nanowires, and porous nanoparticles. The porous ZnOnanoparticles were prepared using a simple thermal decomposition of a sheet-like hydrozincite, whereas the nanorods and nanowires were grown byhydrothermal and chemical vapor deposition methods, respectively. Themorphology and crystal structure of the synthesized materials were charac-terized by field-emission scanning electron microscopy and x-ray diffraction.Ethanol gas-sensing characteristics were systematically studied at differenttemperatures. Our findings show that for ethanol gas-sensing applications,ZnO porous nanoparticles exhibited the best sensitivity, followed by thenanowires and nanorods. Gas-sensing properties were also examined withrespect to the role of crystal growth orientation, crystal size, and porosity.

    Nyckelord
    ZnO, porous nanoparticles, nanorods, nanowires, gas sensors
    Nationell ämneskategori
    Annan materialteknik
    Identifikatorer
    urn:nbn:se:uu:diva-320148 (URN)10.1007/s11664-016-5270-2 (DOI)000400560400019 ()
    Tillgänglig från: 2017-04-16 Skapad: 2017-04-16 Senast uppdaterad: 2017-06-14Bibliografiskt granskad
    5. Influence of annealing temperature on the performance of on-chip hydrothermally grown ZnO nanorod gas sensor toward NO2
    Öppna denna publikation i ny flik eller fönster >>Influence of annealing temperature on the performance of on-chip hydrothermally grown ZnO nanorod gas sensor toward NO2
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    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Nanorod-based gas sensors synthesized at low temperature should generally be annealed before usage. However, the influence of annealing on the sensing performance of these nanorods is rarely reported. In this study, we first fabricated gas sensors based on ZnO nanorods grown on-chip on glass substrate using hydrothermal method. Subsequently, these sensors were annealed at either 400 °C, 500 °C, or 600 °C in air for 4 h. The gas-sensing performance of the ZnO nanorods toward NO2 was tested before and after annealing. The sensitivity of the gas sensors to NO2 decreased, but the stability increased with the increase in annealing temperature. Photoluminescence spectroscopy and X-ray diffraction were used to investigate the material structure of ZnO nanorods. Results revealed that the oxygen-atom-related defects in the ZnO lattice in the region close to the surface influenced by annealing process were the most significant factors on the sensing properties and stability of ZnO nanorods.

    Nyckelord
    zinc oxide; gas sensor; defects in nanorods; annealing; hydrothermal
    Nationell ämneskategori
    Annan materialteknik
    Identifikatorer
    urn:nbn:se:uu:diva-320155 (URN)
    Tillgänglig från: 2017-04-16 Skapad: 2017-04-16 Senast uppdaterad: 2017-04-24
    6. On-chip growth of patterned ZnO nanorod sensors with PdO decoration for enhancement of hydrogen-sensing performance
    Öppna denna publikation i ny flik eller fönster >>On-chip growth of patterned ZnO nanorod sensors with PdO decoration for enhancement of hydrogen-sensing performance
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    2017 (Engelska)Ingår i: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 42, nr 25, s. 16294-16304Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this study, we used a low-temperature hydrothermal technique to fabricate arrays of sensors with ZnO nanorods grown on-chip. The sensors on the glass substrate then were sputter decorated with Pd at thicknesses of 2, 4, and 8 nm and annealed at 650 °C in air for an hour. Scanning electron microscopy, high resolution transmission microscopy, X-ray diffraction, and surface analysis by X-ray photoelectron spectroscopy characterization demonstrated that decoration of homogenous PdO nanoparticles on the surface of ZnO nanorods had been achieved. The sensors were tested against three reducing gases, namely hydrogen, ethanol, and ammonia, at 350, 400, and 450 °C. The ZnO nanorods decorated with PdO particles from the 2 and 4 nm layers showed the highest responses to H2 at 450 and 350 °C, respectively. These samples also generally exhibited better selectivity for hydrogen than for ethanol and ammonia at the same concentrations and at all tested temperatures. However, the ZnO nanorods decorated with PdO particles from the 8 nm layer showed a reverse sensing behaviour compared with the first two. The sensing mechanism behind these phenomena is discussed in the light of the spillover effect of hydrogen in contact with the PdO particles as well as the negative competition of the PdO thin film formed between the sensor electrodes during sputter decoration, Pd-Zn heterojunction that forms at high temperature and thus influences the conductivity of the ZnO nanorods.

    Nyckelord
    Hydrogen-sensing at high temperature; On-chip hydrothermal growth; ZnO nanorods; Sputter-decoration; PdO nanoparticles
    Nationell ämneskategori
    Annan materialteknik
    Identifikatorer
    urn:nbn:se:uu:diva-320156 (URN)10.1016/j.ijhydene.2017.05.135 (DOI)000405251500028 ()
    Tillgänglig från: 2017-04-16 Skapad: 2017-04-16 Senast uppdaterad: 2017-10-10Bibliografiskt granskad
  • 220.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Chien, Nguyen Viet
    International Training Institute for Materials Science -ITIMS, Hanoi University of Science and Technology.
    Duy, Nguyen Van
    International Training Institute for Materials Science -ITIMS, Hanoi University of Science and Technology.
    Hoa, Nguyen Duc
    International Training Institute for Materials Science -ITIMS, Hanoi University of Science and Technology.
    Hieu, Nguyen Van
    International Training Institute for Materials Science -ITIMS, Hanoi University of Science and Technology.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    On-chip hydrothermal growth of ZnO nanorods at low temperature for highly selective NO2 gas sensor2016Ingår i: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 169, s. 231-235Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    ZnO nanorods were selectively grown on-chip with a two-step low-temperature hydrothermal method and their gas sensing properties were investigated. Small zinc islands were deposited by sputtering on a glass substrate and used as nucleation sites for the ZnO nanorod growth. An equimolar aqueous solution of 0.005 M Zn(NO3)(2)center dot 6H(2)O and (CH2)(6)N-4 at 85 center dot C was used in two steps. The first step was used for nucleation and growth of short ZnO nanorods for 4 h, whereas the second step was used for elongation of the nanorods for 36 h. Long porous nanorods from neighboring islands connected to each other and formed nanorod junctions. A gas sensor with such nanorods was evaluated towards NO2, ethanol, hydrogen, and ammonia to characterize its sensing properties. It showed that the gas sensor has the highest sensitivity to NO2, and a very high selectivity to this gas when measured at 450 degrees C.

  • 221.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Pd decoration of on-chip grown ZnO nanorods for ethanol detection2016Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    We have decorated on - chip grown ZnO nanorods (NRs) with Pd particles by sputtering for better ethanol detection . Size of the sputtered Pd particles determines response of the ZnO NRs to ethanol . ZnO - Pd 2 nm sample is about twice to three times more sensitive to ethanol compared with ZnO - Pd 4 nm and ZnO - Pd 8 nm samples depending on temperature and concentration of ethanol . ZnO - Pd 2 nm response s and recover s also very fast , e specially at 450 °C . Bigger Pd particles will worsen and even terminate sensing performance of the sensor to ethanol , as seen with 4 nm and 8 nm Pd.

  • 222.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Duc Hoa
    Nguyen, Van Duy
    Nguyen, Van Hieu
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Controlled Synthesis and Understanding of GrowthMechanism: Parameters for Atmospheric PressureHydrothermal Synthesis of Ultrathin SecondaryZnO Nanowires2016Ingår i: Journal of Scientific Research and Reports, ISSN 2320-0227, E-ISSN 2320-0227, Vol. 9, nr 5, s. 1-10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Synthesis of ultrathin ZnO nanowires gains great attention from research community because oftheir large potential in applications involving optoelectronics and sensors. In this study, a lowpressure and low-temperature hydrothermal synthesis of ultrathin ZnO nanowires is studied tounderstand the growth mechanisms better. To achieve this aim, an about 10 nm thin Zn seed layerwas sputter-deposited on a silicon (100) wafer for the hydrothermal growth of ZnO nanowires in anequimolar aqueous solution of Zn(NO3)2 and hexamethylenetetramine. X-ray diffraction analysis confirmed that the Zn layer was self-oxidized into ZnO in air soon after deposition and thenfunctioned as the seed for the preferred growth of c-oriented ZnO nanorods. Different growthconditions were investigated to identify how concentration, temperature, and time influence the finalmorphology of the synthesized ZnO nanostructures. It was found that under the atmosphericpressure, concentration and temperature have to be higher than 0.0025 M and 50°C, respectively,for the ZnO nanorods to nucleate and grow densely. Low concentration gives sparse and randomlyoriented nanorods, whereas high concentration gives dense and vertical nanorods. Ultrathin ZnOsecondary nanowires with an average diameter of less than 20 nm were successfully synthesizedin a solution with concentration of 0.005 M at 90°C for about 16 h. By analyzing the scanningelectron microscopy images of the ZnO nanostructures obtained at different growth conditions, amechanism is proposed for the growth of the ultrathin secondary ZnO nanowires. This findingprovides a cost-effective and straightforward pathway to prepare ultrathin ZnO nanowires.

  • 223.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Investigation on parametersfor hydrothermal synthesis of uniform ZnO nanowires with diameter of 20 nm2014Ingår i: Proceedings of the 10th Micronano System Workshop (MSW 2014), 2014, Uppsala, 2014Konferensbidrag (Refereegranskat)
  • 224.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, van Duy
    Hanoi University of Science and Technology, Vietnam.
    Nguyen, Viet Chien
    Hanoi University of Science and Technology, Vietnam.
    Nguyen, Duc Hoa
    Hanoi University of Science and Technology, Vietnam.
    Nguyen, Van Hieu
    Hanoi University of Science and Technology, Vietnam.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Comparison of NO2 Gas-Sensing Properties of Three Different ZnO Nanostructures Synthesized by On-Chip Low-Temperature Hydrothermal Growth2018Ingår i: Journal of Electronic Materials, ISSN 0361-5235, E-ISSN 1543-186X, Vol. 47, nr 1, s. 785-793Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three different ZnO nanostructures, dense nanorods, dense nanowires, and sparse nanowires, were synthesized between Pt electrodes by on-chip hydrothermal growth at 90°C and below. The three nanostructures were characterized by scanning electron microscopy and x-ray diffraction to identify their morphologies and crystal structures. The three ZnO nanostructures were confirmed to have the same crystal type, but their dimensions and densities differed. The NO2 gas-sensing performance of the three ZnO nanostructures was investigated at different operation temperatures. ZnO nanorods had the lowest response to NO2 along with the longest response/recovery time, whereas sparse ZnO nanowires had the highest response to NO2 and the shortest response/recovery time. Sparse ZnO nanowires also performed best at 300°C and still work well and fast at 200°C. The current–voltage curves of the three ZnO nanostructures were obtained at various temperatures, and the results clearly showed that sparse ZnO nanowires did not have the linear characteristics of the others. Analysis of this phenomenon in connection with the highly sensitive behavior of sparse ZnO nanowires is also presented.

  • 225.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Van Duy
    Hanoi Univ Sci & Technol, ITIMS, Hanoi, Vietnam.
    Nguyen, Viet Chien
    Hanoi Univ Sci & Technol, ITIMS, Hanoi, Vietnam.
    Nguyen, Duc Hoa
    Hanoi Univ Sci & Technol, ITIMS, Hanoi, Vietnam.
    Nguyen, Van Hieu
    Hanoi Univ Sci & Technol, ITIMS, Hanoi, Vietnam.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    On-chip growth of patterned ZnO nanorod sensors with PdO decoration for enhancement of hydrogen-sensing performance2017Ingår i: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 42, nr 25, s. 16294-16304Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, we used a low-temperature hydrothermal technique to fabricate arrays of sensors with ZnO nanorods grown on-chip. The sensors on the glass substrate then were sputter decorated with Pd at thicknesses of 2, 4, and 8 nm and annealed at 650 °C in air for an hour. Scanning electron microscopy, high resolution transmission microscopy, X-ray diffraction, and surface analysis by X-ray photoelectron spectroscopy characterization demonstrated that decoration of homogenous PdO nanoparticles on the surface of ZnO nanorods had been achieved. The sensors were tested against three reducing gases, namely hydrogen, ethanol, and ammonia, at 350, 400, and 450 °C. The ZnO nanorods decorated with PdO particles from the 2 and 4 nm layers showed the highest responses to H2 at 450 and 350 °C, respectively. These samples also generally exhibited better selectivity for hydrogen than for ethanol and ammonia at the same concentrations and at all tested temperatures. However, the ZnO nanorods decorated with PdO particles from the 8 nm layer showed a reverse sensing behaviour compared with the first two. The sensing mechanism behind these phenomena is discussed in the light of the spillover effect of hydrogen in contact with the PdO particles as well as the negative competition of the PdO thin film formed between the sensor electrodes during sputter decoration, Pd-Zn heterojunction that forms at high temperature and thus influences the conductivity of the ZnO nanorods.

  • 226.
    Jiao, Mingzhi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen Viet, Chien
    Hanoi University of Science and Technology.
    Duy, Nguyen Van
    Hanoi University of Science and Technology.
    Nguyen Duc, Hoa
    Hanoi University of Science and Technology.
    Hieu, Nguyen Van
    Hanoi University of Science and Technology.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Influence of annealing temperature on theperformance and stability of on-chip hydrothermally grown ZnO nanorod gassensor toward NO22018Ingår i: Academia Journal of Scientific Research, ISSN 2315-7712, Vol. 6, nr 5, s. 180-189Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nanorod-based gas sensors synthesized at low temperature should generally be stabilized by anneling before usage. However, the influence of annealing on the sensing performance and stability of these nanorods is rarely reported. In this study, we first fabricated gas sensors based on ZnO nanorods grown on-chip on glass substrate using hydrothermal method. Subsequently, these sensors were annealed at either 400 °C, 500 °C, or 600 °C in air for 4 h. The gas-sensing performance of the ZnO nanorods toward NO2 was tested before and after annealing. The sensitivity of the gas sensors to NO2 decreased, but the stability increased with the increase in annealing temperature. Photoluminescence spectroscopy and X-ray diffraction were used to investigate the material structure of ZnO nanorods. Results revealed that the oxygen-atom-related defects in the ZnO lattice in the region close to the surface influenced by annealing process were the most significant factors on the sensing properties and stability of ZnO nanorods.

  • 227.
    Jobs, Magnus
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Rydberg, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A Tunable Spherical Cap Microfluidic Electrically Small Antenna2013Ingår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 9, nr 19, s. 3230-3234Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a novel microfluidic three-dimensional elec- trically small antenna (ESA). It is easy to construct simply by pneumatically inflating a planar stretchable liquid alloy microfluidic antenna into a spherical cap. Its center frequency is tuned when it is inflated; demonstrating combined high efficiency and a wide tunable frequency range around its hemispherical shape.

  • 228.
    Jocic, Simonne
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Mestres, Gemma
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Cross-linked gelatin/agarose conjugate as a thermostable and biocompatible microfluidic material2016Konferensbidrag (Refereegranskat)
  • 229.
    Jocic, Simonne
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Mestres, Gemma
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Science for Life Laboratory, SciLifeLab. Lund University, Dept. Biomedical Engineering, Lund 221 00, Sweden.
    Fabrication of user-friendly and biomimetic 1,1′-carbonyldiimidazole cross-linked gelatin/agar microfluidic devices2017Ingår i: Materials science & engineering. C, biomimetic materials, sensors and systems, ISSN 0928-4931, E-ISSN 1873-0191, Vol. 76, s. 1175-1180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have developed a straightforward technique for fabricating user-friendly and biomimetic microfluidic devices out of a gelatin/agar gel cross-linked with 1,1′-carbonyldiimidazole. The fabrication procedure requires only inexpensive starting materials such as glass capillaries and wires to mold 3D cylindrical channels into the gel with the possibility of achieving channel diameters of 375 μm and 1000 μm. We demonstrate that the channel absent of gel injury can retain fluid within its dimensions for at least 7 h. We also show that the device material does not autofluoresce nor provide hindrances with fluorescent imaging. A discussion of the chemical linkage identities of cross-linked gelatin/agar is included via ATR-FTIR studies. Crosslinking of the gelatin/agar is further confirmed by the lack of a gel to sol transition at physiological temperature as assessed by DSC measurements. SEM micrographs that demonstrate the 100 nm mean pore width of the cross-linked gelatin/agar are provided. This device is considered biomimetic because it represents components present in the natural extracellular matrix such as collagen and proteoglycans in the form of cross-linked gelatin/agar.

  • 230.
    Johansson, Linda
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Enlund, Johannes
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Johansson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Katardjiev, Ilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wiklund, M
    Dept of Applied Physics, Albanova/KTH , Stockholm.
    Yantchev, Ventislav
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Surface acoustic wave-induced precise particle manipulation in a trapezoidal glass microfluidic channel2012Ingår i: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 22, nr 2, s. 025018-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Surface acoustic wave (SAW) excitation of an acoustic field in a trapezoidal glass microfluidic channel for particle manipulation in continuous flow has been demonstrated. A unidirectional interdigital transducer (IDT) on a Y-cut Z-propagation lithium niobate (LiNbO3) substrate was used to excite a surface acoustic wave at approximately 35 MHz. An SU8 layer was used for adhesive bonding of the superstrate glass layer and the substrate piezoelectric layer. This work extends the use of SAWs for acoustic manipulation to also include glass channels in addition to prior work with mainly poly-di-methyl-siloxane channels. Efficient alignment of 1.9 mu m polystyrene particles to narrow nodal regions was successfully demonstrated. In addition, particle alignment with only one IDT active was realized. A finite element method simulation was used to visualize the acoustic field generated in the channel and the possibility of 2D alignment into small nodal regions was demonstrated.

  • 231.
    Johansson, Linda
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Enlund, Johannes
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Johansson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Katardjiev, Ilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Yantchev, Ventsislav
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Surface acoustic wave induced particle manipulation in a PDMS channel: principle concepts for continuous flow applications2012Ingår i: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 14, nr 2, s. 279-289Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A device for acoustic particle manipulation in the40 MHz range for continuous-flow operation in a 50 μm wide PDMS channel has been evaluated. Unidirectionalinterdigital transducers on a Y-cut Z-propagation lithiumniobate wafer were used to excite a surface acoustic wavethat generated an acoustic standing wave inside the microfluidicchannel. It was shown that particle alignment nodeswith different inter-node spacing could be obtained,depending on device design and driving frequency. Theobserved inter-node spacing differed from the standard halfwavelengthinter-node spacing generally employed in bulkacoustic transducer excited resonant systems. This effectand the related issue of acoustic node positions relative thechannel walls, which is fundamental for most continuousflow particle manipulation operations in channels, wasevaluated in measurements and simulations. Specificapplications of particle separation and alignment wherethese systems can offer benefits relative state-of the artdesigns were identified.

  • 232.
    Johansson, Linda
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Evander, Mikael
    Lilliehorn, Tobias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Almqvist, Monica
    Nilsson, Johan
    Laurell, Thomas
    Johansson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Temperature and trapping characterization of an acoustic trap with miniaturized integrated transducers - towards in-trap temperature regulation2013Ingår i: Ultrasonics, ISSN 0041-624X, E-ISSN 1874-9968, Vol. 53, nr 5, s. 1020-1032Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An acoustic trap with miniaturized integrated transducers (MITs) for applications in non-contact trapping of cells or particles in a microfluidic channel was characterized by measuring the temperature increase and trapping strength. The fluid temperature was measured by the fluorescent response of Rhodamine B in the microchannel. The trapping strength was measured by the area of a trapped particle cluster counter-balanced by the hydrodynamic force. One of the main objectives was to obtain quantitative values of the temperature in the fluidic channel to ensure safe handling of cells and proteins. Another objective was to evaluate the trapping-to-temperature efficiency for the trap as a function of drive frequency. Thirdly, trapping-to-temperature efficiency data enables identifying frequencies and voltage values to use for in-trap temperature regulation. It is envisioned that operation with only in-trap temperature regulation enables the realization of small, simple and fast temperature-controlled trap systems. The significance of potential gradients at the trap edges due to the finite size of the miniaturized transducers for the operation was emphasized and expressed analytically. The influence of the acoustic near field was evaluated in FEM-simulation and compared with a more ideal 1D standing wave. The working principle of the trap was examined by comparing measurements of impedance, temperature increase and trapping strength with impedance transfer calculations of fluid-reflector resonances and frequencies of high reflectance at the fluid-reflector boundary. The temperature increase was found to be moderate, 7 degrees C for a high trapping strength, at a fluid flow of 0.5 mm s(-1) for the optimal driving frequency. A fast temperature response with a fall time of 8 s and a rise time of 11 s was observed. The results emphasize the importance of selecting the proper drive frequency for long term handling of cells, as opposed to the more pragmatic way of selecting the frequency of the highest acoustic output. Trapping was demonstrated in a large interval between 9 and 11.5 MHz, while the main trapping peak displayed FWHM of 0.5 MHz. A large bandwidth enables a more robust manufacturing and operation while allowing the trapping platform to be used in applications where the fluid wavelength varies due to external variations in fluid temperature, density and pressure. 

  • 233.
    Johansson, Linda
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Johansson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nikolajeff, Fredrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thorslund, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Effective mixing of laminar flows at a density interface by an integrated ultrasonic transducer2009Ingår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 9, nr 2, s. 297-304Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An acoustic mixer for glass channel microfluidic systems is presented. An acoustic standing wave, perpendicular to the fluid flow, is generated by the excitation of a miniaturized piezoelectric transducer operated around 10 MHz. The transducer is fabricated into a planar printed circuit board structure, constituting the bottom channel wall, which makes the mixer simple to integrate with a wide selection of microfluidic channel designs. The mixing occurs at a fluid-fluid density interface due to the acoustic radiation force; an analytical expression is derived to qualitatively describe this phenomenon. Only a small density difference in the range of 2–5% is required to achieve 150–270% peak broadening of a fluorescent sample between sheath flows, which we use as a measure of the mixing efficiency. The mixing efficiency is measured with regard to its sensitivity to the density difference, the fluid velocity and the transducer driving frequency. Transducers at different positions along the microchannel make it possible to compare the mixing of straight versus diagonal flows across the transducer surface. We finally demonstrate enhanced chemical lysis of E. coli K12 cells in the device due to active fluid mixing.

  • 234.
    Johansson, Sofia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Porras, Ana Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Searle, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Barbe, Laurent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kubart, Tomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Organs-on-Chip System with Integrated Transparent Conductive Oxide Electrodes2018Konferensbidrag (Refereegranskat)
  • 235.
    Johansson, Sofia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Porras, Ana Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Searle, Sean
    Dept. Biomedical Engineering, National University of Singapore.
    Barbe, Laurent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Integrated transparent electrodes in an organs-on-chip system2018Konferensbidrag (Refereegranskat)
  • 236.
    Johansson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Micro- and Nanomanipulation for Nanomanufacturing2014Ingår i: Encyclopedia of Nanotechnology / [ed] Bhushan, Bharat, springer , 2014, s. 1-17Kapitel i bok, del av antologi (Refereegranskat)
  • 237.
    Jonsson, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik, Ångström Space Technology Centre (ÅSTC).
    Microsystems Technology for Underwater Vehicle Applications2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis work has been to investigate how miniaturization, such as microsystems technology, can potentially increase the scientific throughput in exploration of hard-to-reach underwater environments, such as the subglacial lakes of Antarctica, or other challenging environments, including cave systems and wrecks. A number of instruments and subsystems applicable to miniature submersibles have been developed and studied, and their potential to provide a high functionality density for size-restricted exploration platforms has been assessed.

    To provide an onboard camera system with measurement capabilities, simulation and design tools for diffractive optics were developed, and microoptics realized to project reference patterns onto objects to reveal their topography. The influence of murky water on the measurement accuracy was also studied.

    For longer-range mapping of the surroundings, and under conditions with even less visibility, the performance of a very small, high-frequency side-scanning sonar was investigated using extensive modeling and physical testing. In particular, the interference on the acoustic beam from tight mounting in a hull was investigated. A range in excess of 30 m and centimeter resolution were obtained.

    Besides these systems, which can be used to navigate and map environments, a two-dimensional, thermal sensor for minute flows was developed. Measuring speed and direction of water flows, this sensor can aid in the general classification of the environment and also monitor the submersible’s movement. As the flow of waters in subglacial lakes is estimated to be minute, the detection limit and sensitivity were investigated.

    Measurements of water properties are facilitated by the chip-based conductivity, temperature, and depth sensor system developed. Macroscopically, this is an essential oceanographic instrument with which salinity is determined. Contrary to what was expected, MHz frequencies proved to be advantageous for conductivity measurements.

    Finally, sampling of water using an acoustically enriching microdevice, and even enabling return of pristine samples via the use of integrated latchable, high-pressure valves, was realized and evaluated. Particularly, investigations of the device’s ability to capture and hold on to microorganisms, were conducted.

    Further developed and studied, these devices – as subsystems to miniature submersibles, or as stand-alone instruments – should enable exploration of previously unreachable submerged environments.

    Delarbeten
    1. Simulation, manufacturing, and evaluation of a sonar for a miniaturized submersible explorer
    Öppna denna publikation i ny flik eller fönster >>Simulation, manufacturing, and evaluation of a sonar for a miniaturized submersible explorer
    Visa övriga...
    2010 (Engelska)Ingår i: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 57, nr 2, s. 490-495Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Single-beam side-scan sonar elements, to be fitted on a miniaturized submersible, are here simulated, manufactured, and evaluated. Finite element analysis simulations are compared with measurements, and an overall observation is that the agreement between simulations and measurements deviates from the measured values of 1.5 to 2°, for the narrow lobe angle, by less than 10% for most models. An overall finding is that the lobe width along the track direction can be accurately simulated and, hence, the resolution of the sonars can be predicted. This paper presents, to the authors’ knowledge, the world’s smallest side-scan sonars.

    Nyckelord
    Sonar, beam width, acoustic imaging
    Nationell ämneskategori
    Strömningsmekanik och akustik
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-121440 (URN)10.1109/TUFFC.2010.1429 (DOI)000274817300023 ()
    Projekt
    Deeper Access, Deeper Understanding (DADU)
    Anmärkning

    This article is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, this work may not be reposted without the explicit permission of the copyright holder.

    Tillgänglig från: 2010-03-23 Skapad: 2010-03-23 Senast uppdaterad: 2017-12-12Bibliografiskt granskad
    2. Enclosure-Induced Interference Effects in a Miniaturized Sidescan Sonar
    Öppna denna publikation i ny flik eller fönster >>Enclosure-Induced Interference Effects in a Miniaturized Sidescan Sonar
    Visa övriga...
    2012 (Engelska)Ingår i: IEEE Journal of Oceanic Engineering, ISSN 0364-9059, E-ISSN 1558-1691, Vol. 37, nr 2, s. 236-243Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    On, for instance, the miniaturized submersible explorer, Deeper Access, Deeper Understanding (DADU), only 20 cm in length and 5 cm in diameter, the sidescan sonar needs to be tightly mounted in the hull. Finite element analysis (FEA) as well as physical measurements were used to investigate the effects of beam interaction with acoustically nearby rigid boundaries. Computer simulations showed the first major dip in the beam shape to vary in strength, size, and position with the enclosure wall height, from a position of 47° at 0.0-mm wall height to 32° at 3.0-mm wall height. Hydrophonic measurements on the manufactured test device confirmed these values to within 9%, varying between 47° and 29°. In addition, Schlieren imaging was proposed and used as a noninvasive means of qualitative beam shape characterization. A field test was performed with the enclosure height set to 0 and 3 mm. With the latter height, a dark band, corresponding to a sonar sensitivity dip at about 30° in the beam, appeared in the sonar image. It was found that the beam shape is sensitive to small mounting errors, in this case where the wavelength of the sonar is on the same size scale as the enclosure. Furthermore, it was found that FEA models can be used to accurately predict enclosure effects on sonar beam shapes, and Schlieren imaging can be used to visually detect the shape deformations in mounted sonar devices.

    Nyckelord
    Beam shape, finite element analysis (FEA), miniaturize, Schlieren, sidescan sonar
    Nationell ämneskategori
    Strömningsmekanik och akustik
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171730 (URN)10.1109/JOE.2012.2188160 (DOI)000303326500007 ()
    Projekt
    Deeper Access, Deeper Understanding (DADU)
    Tillgänglig från: 2012-03-26 Skapad: 2012-03-26 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
    3. A compact system to extract topography information from scenes viewed by a miniaturized submersible explorer
    Öppna denna publikation i ny flik eller fönster >>A compact system to extract topography information from scenes viewed by a miniaturized submersible explorer
    Visa övriga...
    2012 (Engelska)Ingår i: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 188, nr SI, s. 401-410Artikel i tidskrift, Meeting abstract (Refereegranskat) Published
    Abstract [en]

    In images taken underwater, it is generally difficult to correctly extract distances and geometric informationof objects. Different techniques, collectively referred to as photogrammetry, exist to measurefeatures in images. One of these is to project a reference pattern onto an object in a scene viewed by acamera, and register the distortion of this pattern, to calculate the shape of, and distance to, that object.This method is implemented here on a miniaturized submersible explorer equipped with, among manyother instruments, a camera. Diffractive optical elements (DOEs) have been designed and manufacturedusing microsystems technology, to, together with a laser diode, camera, and in-house developed software,provide a compact system for projecting reference patterns and analyzing their deformations. Thesystem has been characterized by measuring the distances and angles of objects in a water tank, andattempting to reproduce their shapes. The range of operation of the system, verified to be at least onemeter, is limited by the compact mounting in the small submersible and the cameras’ performance.The system was found to work well under turbid conditions as well as in water containing larger particles.Together with a vehicle-mounted camera, the compact and low-power DOE laser projection systemenables topographical measurement.

    Nyckelord
    Photogrammetry, Diffractive, Laser, Underwater, Images, Miniaturized
    Nationell ämneskategori
    Teknik och teknologier
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171732 (URN)10.1016/j.sna.2012.02.034 (DOI)000312692500054 ()
    Konferens
    The 16th International Conference on Solid-State Sensors, Actuators and Microsystems, 5-9 June, 2011, Beijing, CHINA
    Projekt
    Deeper Access, Deeper Understanding (DADU)
    Tillgänglig från: 2012-03-26 Skapad: 2012-03-26 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
    4. Acoustically enriching, large-depth aquatic sampler
    Öppna denna publikation i ny flik eller fönster >>Acoustically enriching, large-depth aquatic sampler
    Visa övriga...
    2012 (Engelska)Ingår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 12, nr 9, s. 1619-1628Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In marine biology, it is useful to collect water samples when exploring the distribution and diversity of microbial communities in underwater environments. In order to provide, e.g., a miniaturized submersible explorer with the capability of collecting microorganisms, a compact sample enrichment system has been developed. The sampler is 30 mm long, 15 mm wide, and just a few millimetres thick. Integrated in a multilayer steel, polyimide and glass construction is a microfluidic channel with piezoelectric transducers, where microorganism and particle samples are collected and enriched, using acoustic radiation forces for gentle and labelless trapping. High-pressure, latchable valves, using paraffin as the actuation material, at each end of the microfluidic channel keep the collected sample pristine. A funnel structure raised above the surface of the device directs water into the microfluidic channel as the vehicle propels itself or when there is a flow across its hull. The valves proved leak proof to a pressure of 2.1 MPa for 19 hours and momentary pressures of 12.5 MPa, corresponding to an ocean depth of more than 1200 metres. By reactivating the latching mechanism, small leakages through the valves could be remedied, which could thus increase the leak-less operational time. Fluorescent particles, 1.9 µm in diameter, were successfully trapped in the microfluidic channel at flow rates up to 15 ml min-1, corresponding to an 18.5 cm s-1 external flow rate of the sampler. In addition, liquid-suspended GFP-marked yeast cells were successfully trapped.

    Nyckelord
    Acoustic, microorganism, enriching, trap, valve, paraffin, sampler, marine, actuator
    Nationell ämneskategori
    Teknik och teknologier
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171734 (URN)10.1039/C2LC00025C (DOI)000302368200009 ()
    Projekt
    Deeper Access, Deeper Understanding (DADU)
    Tillgänglig från: 2012-03-26 Skapad: 2012-03-26 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
    5. A latchable high-pressure thermohydraulic valve actuator
    Öppna denna publikation i ny flik eller fönster >>A latchable high-pressure thermohydraulic valve actuator
    2012 (Engelska)Ingår i: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 188, s. 292-297Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This work presents a latchable thermohydraulic microactuator for use in high-pressure valves, e.g. for oceanic sampling in missions of long duration. Mounted on a miniature submersible, it can be used in confined spaces to explore previously unreachable environments. However, the device can be used in any high-pressure application where long duration open and/or closed valve states are required, and power consumption is an issue. The actuator is fabricated using standard batch-processes as photochemical machining, wet etching and photolithography. The actuation and latching mechanisms are both thermohydraulic, using solid-to-liquid phase transition of paraffin for actuation and of a low melting point alloy for latching. Focus of this work is on the endurance of the actuator to facilitate a bistable valve. The actuator managed to keep a deflected position for almost 50 hours to the load equivalent to 1.8 MPa applied pressure, after which the experiment was aborted. No pressure dependence was discovered in the latching losses, i.e. the difference in deflection before and after the actuator is powered off. Furthermore, the effect of intermixing of paraffin and the low melting point alloy was evaluated.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2012
    Nyckelord
    Fluid control, Bistable, Steel, Actuator, Paraffin, Low melting point alloy
    Nationell ämneskategori
    Teknik och teknologier
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171755 (URN)10.1016/j.sna.2011.11.027 (DOI)000312692500039 ()
    Konferens
    The 16th International Conference on Solid-State Sensors, Actuators and Microsystems, 5-9 June, 2011, Beijing, CHINA
    Tillgänglig från: 2012-03-27 Skapad: 2012-03-27 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
    6. Two-Dimensional Thermal Velocity Sensor for Submersible navigation and Minute Flow Measurements
    Öppna denna publikation i ny flik eller fönster >>Two-Dimensional Thermal Velocity Sensor for Submersible navigation and Minute Flow Measurements
    2013 (Engelska)Ingår i: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 13, nr 1, s. 359-370Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A 2-D thermal velocity microsensor for use as a navigational aid and for flow measurements on a miniaturized submersible is developed in this paper. The sensor with nickel heater and temperature sensors on a Pyrex substrate, designed for mounting on the outside of the submersible hull, is fabricated and tested in an application-like environment and proven to be able to measure water speed from zero to 40 mm/s with a power consumption less than 15 mW and determine the flow direction with an error less than ±8°. Finite Element Analysis is used to investigate design and operation parameters and possible biofouling effects on the sensor signal. The effect on shape and orientation of the sensor's mounting surface is also studied.

    Nationell ämneskategori
    Annan materialteknik
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171767 (URN)10.1109/JSEN.2012.2216866 (DOI)000313685400028 ()
    Tillgänglig från: 2012-03-27 Skapad: 2012-03-27 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
    7. Towards chip-based salinity measurements for small submersibles and biologgers
    Öppna denna publikation i ny flik eller fönster >>Towards chip-based salinity measurements for small submersibles and biologgers
    2013 (Engelska)Ingår i: International Journal of Oceanography, ISSN 1687-9406, E-ISSN 1687-9414, Vol. 2013, s. 529674-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Water’s salinity plays an important role in the environment. It can be determined by measuring conductivity, temperature, anddepth (CTD). The corresponding sensor systems are commonly large and cumbersome. Here, a 7.5 × 3.5mm chip, containingmicrostructured CTD sensor elements, has been developed. On this, 1.5mm2 gold finger electrodes are used to measure theimpedance, and thereby the conductivity of water, in the MHz frequency range. Operation at these frequencies resulted in highersensitivities than those at sub-MHz frequencies. Up to 14 kΩ per parts per thousand salt concentration was obtained repeatedlyfor freshwater concentrations.This was three orders of magnitude higher than that obtained for concentrations in and above thebrackish range. A platinumelectrode is used to determine a set ambient temperature with an accuracy of 0.005∘C.Membranes withNichrome strain gauges responded to a pressure change of 1 bar with a change in resistance of up to 0.21Ω. A linear fit to data over7 bars gave a sensitivity of 0.1185Ω/bar with an R2 of 0.9964. This indicates that the described device can be used in size-limitedapplications, like miniaturized submersibles, or as a bio-logger on marine animals.

    Ort, förlag, år, upplaga, sidor
    Hindawi Publishing Corporation, 2013
    Nyckelord
    Conductivity, Temperature, Depth, CTD, Pressure, Marine, thin film, micro
    Nationell ämneskategori
    Teknik och teknologier
    Forskningsämne
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-171740 (URN)10.1155/2013/529674 (DOI)
    Projekt
    Deeper Access, Deeper Understanding (DADU)
    Forskningsfinansiär
    Mistra - Stiftelsen för miljöstrategisk forskning
    Tillgänglig från: 2012-03-27 Skapad: 2012-03-27 Senast uppdaterad: 2017-12-07Bibliografiskt granskad
  • 238.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A compact projection system enabling topographical measurements for a miniaturized submersible explorer2011Ingår i: Proceedings of the 16th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS), 2011, IEEE conference proceedings, 2011, s. 2518-2521Konferensbidrag (Refereegranskat)
    Abstract [en]

    To enable photogrammetry of underwater images using a miniaturized submersible explorer, a compact projection system has been developed. By registering the deformation of a known projected pattern, using a laser and a diffractive optical element (DOE), the distance to, shape and size of an object can be calculated. The DOE has been designed, using in-house developed software, and manufactured using microstructure technology. Distances to objects 45 to 30 cm away were determined to within 0.5 cm, and the developed GUI was able to recreate the shape from the measurements for easier examination of the object.

  • 239.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A compact system to extract topography information from scenes viewed by a miniaturized submersible explorer2012Ingår i: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 188, nr SI, s. 401-410Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In images taken underwater, it is generally difficult to correctly extract distances and geometric informationof objects. Different techniques, collectively referred to as photogrammetry, exist to measurefeatures in images. One of these is to project a reference pattern onto an object in a scene viewed by acamera, and register the distortion of this pattern, to calculate the shape of, and distance to, that object.This method is implemented here on a miniaturized submersible explorer equipped with, among manyother instruments, a camera. Diffractive optical elements (DOEs) have been designed and manufacturedusing microsystems technology, to, together with a laser diode, camera, and in-house developed software,provide a compact system for projecting reference patterns and analyzing their deformations. Thesystem has been characterized by measuring the distances and angles of objects in a water tank, andattempting to reproduce their shapes. The range of operation of the system, verified to be at least onemeter, is limited by the compact mounting in the small submersible and the cameras’ performance.The system was found to work well under turbid conditions as well as in water containing larger particles.Together with a vehicle-mounted camera, the compact and low-power DOE laser projection systemenables topographical measurement.

  • 240.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Almqvist, Monica
    Electrical Measurements, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Simulation and Evaluation of Small High-Frequency Side Scan Sonars Using COMSOL2009Ingår i: COMSOL Conference 2009 Milan, 2009Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    High frequency side-scan sonar, to be fitted on a miniaturized submersible explorer, have been simulated and built. The purpose of this study is to see if COMSOL Multiphysics can be used to predict the performance of the sonar, especially the beam width, setting the resolution of the system. Four models were created, from simple 2-D geometries to more complex 3-D models. The simulated beam widths were compared with measurements to see which of the models agreed best. It was found that all models agree with the experimental results to varying degrees, and mostly with a difference of less than 6%. . It was found that the simplest model agreed best with the measurements, closely followed by the most complex model. Also taking the computational load into consideration the simpler model might then be a better choice to use.

  • 241.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Almqvist, Monica
    Electrical Measurements, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Simulation, manufacturing, and evaluation of a sonar for a miniaturized submersible explorer2010Ingår i: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 57, nr 2, s. 490-495Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Single-beam side-scan sonar elements, to be fitted on a miniaturized submersible, are here simulated, manufactured, and evaluated. Finite element analysis simulations are compared with measurements, and an overall observation is that the agreement between simulations and measurements deviates from the measured values of 1.5 to 2°, for the narrow lobe angle, by less than 10% for most models. An overall finding is that the lobe width along the track direction can be accurately simulated and, hence, the resolution of the sonars can be predicted. This paper presents, to the authors’ knowledge, the world’s smallest side-scan sonars.

  • 242.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Lekholm, Ville
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Monica, Almqvist
    Dept of Measurement Technology and Industrial Electrical Engineering, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Enclosure-Induced Interference Effects in a Miniaturized Sidescan Sonar2012Ingår i: IEEE Journal of Oceanic Engineering, ISSN 0364-9059, E-ISSN 1558-1691, Vol. 37, nr 2, s. 236-243Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On, for instance, the miniaturized submersible explorer, Deeper Access, Deeper Understanding (DADU), only 20 cm in length and 5 cm in diameter, the sidescan sonar needs to be tightly mounted in the hull. Finite element analysis (FEA) as well as physical measurements were used to investigate the effects of beam interaction with acoustically nearby rigid boundaries. Computer simulations showed the first major dip in the beam shape to vary in strength, size, and position with the enclosure wall height, from a position of 47° at 0.0-mm wall height to 32° at 3.0-mm wall height. Hydrophonic measurements on the manufactured test device confirmed these values to within 9%, varying between 47° and 29°. In addition, Schlieren imaging was proposed and used as a noninvasive means of qualitative beam shape characterization. A field test was performed with the enclosure height set to 0 and 3 mm. With the latter height, a dark band, corresponding to a sonar sensitivity dip at about 30° in the beam, appeared in the sonar image. It was found that the beam shape is sensitive to small mounting errors, in this case where the wavelength of the sonar is on the same size scale as the enclosure. Furthermore, it was found that FEA models can be used to accurately predict enclosure effects on sonar beam shapes, and Schlieren imaging can be used to visually detect the shape deformations in mounted sonar devices.

  • 243.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Johansson, Linda
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Acoustically enriching, large-depth aquatic sampler2012Ingår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 12, nr 9, s. 1619-1628Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In marine biology, it is useful to collect water samples when exploring the distribution and diversity of microbial communities in underwater environments. In order to provide, e.g., a miniaturized submersible explorer with the capability of collecting microorganisms, a compact sample enrichment system has been developed. The sampler is 30 mm long, 15 mm wide, and just a few millimetres thick. Integrated in a multilayer steel, polyimide and glass construction is a microfluidic channel with piezoelectric transducers, where microorganism and particle samples are collected and enriched, using acoustic radiation forces for gentle and labelless trapping. High-pressure, latchable valves, using paraffin as the actuation material, at each end of the microfluidic channel keep the collected sample pristine. A funnel structure raised above the surface of the device directs water into the microfluidic channel as the vehicle propels itself or when there is a flow across its hull. The valves proved leak proof to a pressure of 2.1 MPa for 19 hours and momentary pressures of 12.5 MPa, corresponding to an ocean depth of more than 1200 metres. By reactivating the latching mechanism, small leakages through the valves could be remedied, which could thus increase the leak-less operational time. Fluorescent particles, 1.9 µm in diameter, were successfully trapped in the microfluidic channel at flow rates up to 15 ml min-1, corresponding to an 18.5 cm s-1 external flow rate of the sampler. In addition, liquid-suspended GFP-marked yeast cells were successfully trapped.

  • 244.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nyholm, Leif
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Oorganisk kemi.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Towards chip-based salinity measurements for small submersibles and biologgers2013Ingår i: International Journal of Oceanography, ISSN 1687-9406, E-ISSN 1687-9414, Vol. 2013, s. 529674-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water’s salinity plays an important role in the environment. It can be determined by measuring conductivity, temperature, anddepth (CTD). The corresponding sensor systems are commonly large and cumbersome. Here, a 7.5 × 3.5mm chip, containingmicrostructured CTD sensor elements, has been developed. On this, 1.5mm2 gold finger electrodes are used to measure theimpedance, and thereby the conductivity of water, in the MHz frequency range. Operation at these frequencies resulted in highersensitivities than those at sub-MHz frequencies. Up to 14 kΩ per parts per thousand salt concentration was obtained repeatedlyfor freshwater concentrations.This was three orders of magnitude higher than that obtained for concentrations in and above thebrackish range. A platinumelectrode is used to determine a set ambient temperature with an accuracy of 0.005∘C.Membranes withNichrome strain gauges responded to a pressure change of 1 bar with a change in resistance of up to 0.21Ω. A linear fit to data over7 bars gave a sensitivity of 0.1185Ω/bar with an R2 of 0.9964. This indicates that the described device can be used in size-limitedapplications, like miniaturized submersibles, or as a bio-logger on marine animals.

  • 245.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Johansson, Linda
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Instrumentation and vehicle platform of a miniaturized submersible for exploration of terrestrial and extraterrestrial aqueous environments2012Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 79, s. 203-211Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An example of an extraterrestrial environment likely to support life is the vast liquid body believed to hide underneath the frozen crust of Jupiter's moon Europa. The hypothetical exploration of this, as well as the more accessible subglacial lakes on Earth, has been used as model applications for the development of a heavily miniaturized, yet qualified, submersible with the potential to be deployable either in itself through a long and narrow borehole or as the daughter craft of an ice-penetrating cryobot.

    Onboard the submersible, which is only 20 cm in length and 5 cm in diameter, accommodation of a versatile set of sensors and instruments capable of characterizing and imaging the surroundings, and even collecting water samples with microorganisms for return, is facilitated through the use of miniaturization technologies. For instance, together with a small camera, a laser-based, microoptic device enables the 3-D reconstruction of imaged objects for topographical measurements. As a complement, when the water is turbid or a longer range is wanted, the world's smallest side-scanning sonar, exhibiting centimeter resolution and a range of over 30 m, has been developed. The work on miniaturizing a CTD, which is a widely employed oceanographic instrument used to measure and correlate conductivity, temperature, and depth, has commenced. Furthermore, a device employing acoustics to trap microscopic particles and organisms, and, by this, enrich water samples, is under development. To ensure that the gathered samples are pristine until analyzed at the end of a mission, the device is equipped with high-pressure, latchable valves.

    Remote operation and transfer of measurement data and images, or even live streaming of video, is made possible through a kilometer-long fiber optic cable being reeled out from the vehicle underway and tethering it to a terminal. To extend the missions, the same fiber shall also be capable of charging the onboard batteries.

    In this paper, the vehicle and its subsystems are summarized. Subsystems essential for the vehicle's operation, e.g., hull structure, communication and power management, are treated separately from those of more mission-specific nature, like the instruments mentioned above.

  • 246.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wagner, Sven
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Miniaturized submersible for exploration of aqueous environments on Earth and beyond2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    Some of the most likely environments to support extraterrestrial life in our solar system are the ice-covered moons, suchas Europa, thought to harbor a liquid ocean underneath its frozen crust. Exploration, however, necessitates an ice-penetratingcryobot, or a long and narrow borehole, and the subsequent deployment of a small submersible, a hydrobot, with severe sizerestrictions imposed on its scientific payload. As a stepping stone for exploration of such environments, a small instrumentladenedsubmersible vehicle is currently under development.Employment of a large set of instruments capable of characterizing the aqueous environment, imaging the surroundingsand collecting microorganisms is essential for the determination of habitability. Despite the submersible being only 20 cm inlength and 5 cm in diameter, a high degree of functionality is facilitated here through the use of miniaturization technologies. Forinstance, a compact laser-illuminated diffractive optical element, paired with a high-resolution camera, enable photogrammetryand the reconstruction of objects’ shapes in 3-D space. Also for imaging, the world’s smallest side-scanning sonar has beendeveloped to acoustically image, either where water is too turbid for the camera, or where longer range is necessary. Currently,the sonar exhibits centimeter resolution and ranges over 30 meters. On the sensor side, a most vital oceanographic instrument, theCTD, used to measure the conductivity, temperature, and depth of water, has been heavily miniaturized and preliminaryevaluated. Additionally, a water sampler combining integrated selection and enriching capabilities to filter out and accommodate,e.g., microbes in the size range of 1-10 μm, is under development. Among other parts, its high-pressure valves and microfluidicacoustic traps have already been realized.For remote operation and upload of measurement data or images, or even live streaming of video, the submersible will betethered with a bi-directionally transmitting fiber optic cable, also capable of charging the onboard batteries for long missions.The one kilometer long fiber will be fitted within the hull, and by reeling out the fiber from the submersible, drag will be reduced.Herein, test results and images of the vehicle and its complete, and continuously developed, subsystems are presented.The vehicle, and its subsystems as stand-alone instruments, will enable the exploration of previously unreachable analogenvironments on Earth, vital to the field of astrobiology, and act as a forerunner to a submersible hydrobot that can explore icecoveredoceans elsewhere in our solar system.

  • 247.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wagner, Sven
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Miniaturized submersible for exploration of small aqueous environments2011Ingår i: Oceans’11 MTS/IEEE Kona, Hilton Waikoloa Village, Kona, Hawai‘i September 19-22, 2011, 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    Remotely operated vehicles (ROVs) are commonlyused for sub-surface exploration. However, multi-functionalROVs tend to be fairly large, while preferred small and compactROVs suffer from limited functionality. The Deeper Access,Deeper Understanding (DADU) project aims to develop a smallsubmersible concept using miniaturization technologies to enablea high functionality. An operator is able to maneuver the vehiclewith five degrees of freedom using eight small thrusters, while aset of accelerometers and gyros monitor the orientation of thesubmersible. A single fiber optic cable will connect thesubmersible to a control station and enable simultaneous dataand command transfers. Rechargeable battery packs providepower to the submersibles subsystems during operation. Thesewill be rechargeable through the fiber connection. A forwardlooking camera is aided by a laser topography measurementsystem, where distances, sizes and shapes of objects in view canbe determined to within 0.5 cm. For murkier environments, orwhen a more extensive mapping of the surroundings is needed,the small high-frequency side-scanning sonar can be used.Salinity calculations of the water will be available throughmeasurements of the conductivity, temperature and depth.Samples of water and particles within it will be enabled through awater sampler with an enriching capability. Flow sensors will beable to measure the water movement around the submersible’shull. The submersible and its subsystems are under continuousdevelopment. The vehicle itself, and its subsystems as stand-aloneinstruments, will enable the exploration of previouslyunreachable submerged environments, such as the sub-glaciallakes found in Iceland and Antarctica, or other submerged smallenvironments, such as pipe and cave systems.

  • 248.
    Jonsson, Linus
    et al.
    Lund University.
    Fornell, Anna
    Lund University.
    Joensson, Haakan
    Royal Institute of Technology.
    Nilsson, Johan
    Lund University.
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Development of a droplet generator towards applications using acoustophoretic sorting2014Konferensbidrag (Övrigt vetenskapligt)
  • 249.
    Karempudi, Praneeth
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär systembiologi.
    Khaji, Zahra
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Vallin, Örjan
    Tenje, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Elf, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär systembiologi.
    Microfluidic chip for large-scale phenotypic characterization of E. coli2019Konferensbidrag (Refereegranskat)
  • 250.
    Karlsson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Development of an Ultra-Sensitive Biosensor Based on Mid-Infrared Diamond Waveguide Spectroscopy2019Konferensbidrag (Refereegranskat)
2345678 201 - 250 av 562
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