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  • 1.
    Ahlén, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signals and Systems Group.
    Ahlgren, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Grönroos, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Gunningberg, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Katardjiev, Ilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rohner, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signals and Systems Group.
    Presentation of the VINN Excellence Center for Wireless Sensor Networks (WISENET)2008In: Conference on Radio Science (RVK08), Växjö, 2008Conference paper (Refereed)
  • 2. Bjerketorp, J.
    et al.
    Ng Tze Chiang, A.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Rosenquist, M.
    Liu, Wen-Tso
    Jansson, J. K.
    Rapid lab-on-a-chip profiling of human gut bacteria2008In: Journal of Microbiological Methods, ISSN 0167-7012, E-ISSN 1872-8359, Vol. 72, no 1, p. 82-90Article in journal (Refereed)
    Abstract [en]

    The human gut microbiota has a substantial impact on human health. Different factors such as disease, diet and drug use can have significant impacts on the gut microbiota. Therefore, it is of interest to have simple, rapid methods for analysis of the composition of the gut microbiota for clinical diagnostic purposes. Since only a minor fraction of the gastrointestinal bacterial community is presently possible to cultivate, molecular approaches are currently the best suited to investigate its composition. However, most of these molecular approaches require technical expertise and expensive equipment to run and they are not routinely available. Ideally, the analyses should be point-of-care options that can be run on a chip. In this study, an existing lab-on-chip (LOC) system for sizing/quantifying DNA was combined with length heterogeneity PCR (LH-PCR), a PCR-based profiling method targeting bacterial 16S rRNA gene sequences, to develop a fast, straightforward, reproducible, and economical method for profiling bacterial communities. The LOC LH-PCR method was first evaluated using a standardized gut cocktail containing genomic DNA from eight different bacterial species representing different genera of relevance for human health. The method was also tested on DNA that was directly extracted from human faecal samples and it was consistently capable of detecting alterations in the bacterial samples before and after antibiotic treatment. Although the resolution of the method needs improvement, this study represents the first step towards development of a diagnostic LOC for profiling gut bacterial communities.

  • 3.
    Bodén, Roger
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Lehto, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Margell, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Schweitz, Jan-Åke
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    On-chip liquid storage and dispensing for lab-on-a-chip applications2008In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 18, no 7, p. 075036-Article in journal (Refereed)
    Abstract [en]

    This work presents novel components for on-chip storage and dispensing inside a lab-on-a-chip (LOC) for applications in immunoassay point-of-care testing (POCT), where incubation and washing steps are essential. It involves easy-to-use on-chip solutions for the sequential thermo-hydraulic actuation of liquids. The novel concept of combining the use of a rubber plug, both as a non-return valve cap and as a liquid injection interface of a sealed reservoir, allows simple filling of a sterilized cavity, as well as the storage and dispensing of reagent and washing buffer liquids. Segmenting the flow with air spacers enables effective rinsing and the use of small volumes of on-chip stored liquids. The chip uses low-resistance resistors as heaters in the paraffin actuator, providing the low-voltage actuation that is preferred for handheld battery driven instruments.

  • 4.
    Bruhn, Fredrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Warell, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics.
    Lagerkvist, Claes-Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics.
    Kaznov, Viktor
    Jones, Jack A
    Stenmark, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    A Preliminary Design for a Spherical Inflatable Microrover for Planetary Exploration2008In: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 63, no 5-6, p. 618-631Article in journal (Refereed)
    Abstract [en]

    The Spherical Mobile Investigator for Planetary Surface (SMIPS) concept aims at making use of the latest developments within extreme miniaturization of space systems. The introduction of Microelectromechanical Systems (MEMSs) and higher level Multifunctional Microsystems (MMSs) design solutions gives the robot high performance per weight unit. The untraditional spherical shape makes it easily maneuverable and thus provides a platform for scientific investigations of interplanetary bodies. Preliminary investigations of the SMIPS concept show several advantages over conventional robots and rovers in maneuverability, coverage, size, and mass. A locomotion proof-of-concept has been Studied together with a new distributed on-board data system configuration. This paper discusses theoretical robot analysis, an overall concept, possible science, enabling technologies, and how to perform scientific investigations. A preliminary design of an inflatable multifunctional shell is proposed.

  • 5.
    Böhnke, Tobias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Division for Electricity and Lightning Research.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hultåker, Annette
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Köhler, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Division for Electricity and Lightning Research.
    Edoff, Marika
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Roos, Arne
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Ribbing, Carl-Gustaf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Surfaces with high solar reflectance and high thermal emittance on structured silicon for spacecraft thermal control2008In: Optical materials (Amsterdam), ISSN 0925-3467, E-ISSN 1873-1252, Vol. 30, no 9, p. 1410-1421Article in journal (Refereed)
    Abstract [en]

    Presented here is an examination of unstructured and structured (by anisotropic etching), monocrystalline silicon wafers coated with sputter deposited aluminum and chemical vapor deposited silicon dioxide for high solar reflectance and high thermal emittance, respectively. The topography of the samples was characterized with optical and scanning electron microscopy. Optical properties were examined with reflectance and transmittance spectroscopy, partly by usage of an integrating sphere. The measurement results were used to estimate the equilibrium temperature of the surfaces in space. The suitability of the surfaces with high solar reflectance and high thermal emittance to aid in the thermal control of miniaturized, highly integrated components for space applications is discussed. A silicon dioxide layer on a metal layer results in a slightly lower reflectance when compared to surfaces with only a metal layer, but might be beneficial for miniaturized space components and modules that have to dissipate internally generated heat into open space. Additionally, it is an advantage to microstructure the emitting surface for enhanced radiation of excess heat.

  • 6.
    Edqvist, Erik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Mikrostrukturteknik.
    Polymer Actuators for Micro Robotic Applications2007Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis a multilayer actuator structure is developed for the I-SWARM project. In order to build an energy efficient and low voltage actuator system for the 3x3x3 mm3 robot, the resonance drive mode in combination with a ten layer multilayer structure build upon the most suitable substrate material was used. Two different sizes of the locomotion module were built. The first one is five times larger than the small version. It has five active layers and is simpler to work with and to test. The small module has three 2x0.4 mm can-tilevers on a 3x3mm body and ten active layers.

    The multilayer process involve easily defined flexible printed circuit (FPC) board as substrate material, spin coating piezoelectric poly(vinylidenefluoride- tetrafluoroethylene) P(VDF-TrFE) as active stack material, and evaporated aluminum electrodes on each active polymer layer. By using different shadow masks for each electrode layer, special inter con-tact areas can be contacted from above after the polymer has been removed by an Inductively Coupled Plasma (ICP) etch. The contours of the locomo-tion module was etched in a Reactive Ion Etch (RIE) equipment. Both the cupper layer in the FPC and the electrode layers of the active stack, were used as etch mask.

    The deflections of the cantilevers were measured at low voltages to ensure as realistic drive voltage as possible for the I-SWARM robot. The large struc-ture showed a 250 µm deflection at 4 V and 170 Hz resulting in a Q-value of 19. The deflection of the small structure was 8 µm at 3.3 V and 5000 Hz and the measured Q-value was 31.

  • 7.
    Edqvist, Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Snis, Niklas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Gentle dry etching of P(VDF-TrFE) multilayer micro actuator structures by use of an inductive coupled plasma2008In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 18, no 1, p. 015007-Article in journal (Refereed)
    Abstract [en]

    To fully utilize the actuator properties of poly(vinylidenefluoride) (P(VDF))-based polymers, the electric field has to be rather high and one way to accomplish this, in particular with low voltage drive signals, is to build multilayered structures. This paper focuses on how to structure poly(vinylidenefluoride-trifluoroethylene) P(VDF-TrFE) by presenting an etch method to create multilayered miniaturized actuators, with intermediate aluminium electrodes. To create inter-connect areas for the multilayer electrodes, a modified Bosch process in an inductive couple plasma (ICP) etcher is used to remove all P(VDF-TrFE) not covered by the electrodes. Since each electrode mask is slightly different from the others, the result is a staircase-like inter-electrode contact area that is connected from above using a conductive adhesive. The developed ICP etch results in high selective etching and a good agreement between theoretical and measured capacitance values. The manufactured cantilevers, consisting of a multilayer on top of a flexible printed circuit (FPC) board, were tested and the resonant stroke was confirmed to agree with expected values. The successful establishment of interlayer connections between the electrodes open up the possibility for batch fabrication of cheap low voltage micro actuators built on a standard substrate used in millions of commercial products. 2008 IOP Publishing Ltd.

  • 8.
    Enlund, Johannes
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Johansson, Linda
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Surface Acoustic Wave-induced particle manipulation in a glass microfluidic channelIn: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439Article in journal (Refereed)
  • 9.
    Gunningberg, Per
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Grönroos, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Katardjiev, Ilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electronics.
    Voigt, Thiemo
    SICS.
    Ahlén, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signal Processing.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signal Processing.
    WISENET Wireless Sensor Networks VINN Excellence Center2007Other (Other academic)
    Abstract [en]

    This broschure was produced for the inauguration of WISENET December 7, 2007. It decribes the future impact of WISENET, application areas and the 10 partners. The three research areas "Node Integration & Energy", "Networkning & Security" and "Wireless Communication" is briefly described as well as the application projects in "Water Sensing" and "Transport".

  • 10. Hedsten, Karin
    et al.
    Melin, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Bengtsson, Jörgen
    Modh, Peter
    Karlén, David
    Löfving, Björn
    Nilsson, Richard
    Rödjegård, Hendrik
    Persson, Katrin
    Enoksson, Perter
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Andersson, Gert
    MEMS-based VCSEL beam steering using replicated polymer diffractive lens2008In: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 142, no 1, p. 336-345Article in journal (Refereed)
    Abstract [en]

    This paper describes a fully integrated micro-optical system, in which dynamic angular control of the beam from a vertical cavity surface emitting laser (VCSEL) is realized by laterally moving a collimating diffractive lens in the light path. The lens is mounted on a translatable silicon stage, which consists of a frame with an opening for the light to traverse the lens and electro-statically driven comb actuators, by which the lateral movement is achieved. Devices implementing both one-(1D) and two-dimensional (2D) scanning have been fabricated and evaluated. Integration of the lens onto the translatable silicon stage is done using a newly developed fabrication process based on hot embossing of an amorphous fluorocarbon polymer. This fabrication process relies on a reversed-order protocol, where the structuring of the optical element precedes the silicon microstructuring. Assembly and packaging of the VCSEL-MOEMS system, using low temperature cofired ceramic (LTCC) technique, is also demonstrated. Optical evaluation of the system and beam steering function shows significant beam deflection for a relatively low driving voltage (similar to 70 V).

  • 11.
    Hjort, Klas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Yousef, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Lindeberg, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Ion track lithography for flexible PCB manufacturing2008In: International Confonference on Atomic Collisions in Solids – ICACS23, 2008, p. 61-66Conference paper (Refereed)
  • 12.
    Jensen, Jens
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    Kubart, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Martin, David
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Surpi, A
    Blom, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Experimental Physics.
    Topalian, Z
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Yousef, H
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Sanz, R
    Damage formation in TiO2 by heavy ions: consequences for micro- and nano-struring2008In: 7th International Symposium on Swift Heavy Ions in Matter (SHIM2008), Lyon, France, 2008Conference paper (Refereed)
  • 13.
    Jensen, Jens
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    Skupinski, Marek
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Sanz, R
    Heavy ion beam-based nano- and micro-structuring of TiO2 single crystals using self-assembled masks2008In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, ISSN 0168-583X, E-ISSN 1872-9584, Vol. 266, no 12-13, p. 3113-3119Article in journal (Refereed)
    Abstract [en]

    Fast heavy ion beam-based lithography using masks of self-assembled materials has been applied for transferring well-ordered nano- and micropatterns to rutile TiO2 single crystals. As the induced damage has a high etching selectivity the patterns can be developed in hydrofluoric acid with very high-contrast. Here we present resulting patterns when using a mask of self-ordered silica spheres. The obtained pattern are replicas of the mass distribution of the mask. In addition the shape and size of the regular structures depend on the applied ion energy and fluence. Direct modifications of the optical properties of TiO2 in a well-defined pattern are also presented. (c) 2008 Elsevier B.V. All rights reserved.

  • 14.
    Johansson, Linda
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Acoustic Manipulation of Particles and Fluids in Microfluidic Systems2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The downscaling and integration of biomedical analyses onto a single chip offers several advantages in speed, cost, parallelism and de-centralization. Acoustic radiation forces are attractive to use in these applications since they are strong, long-range and gentle. Lab-on-a-chip operations such as cell trapping, particle fluorescence activated cell sorting, fluid mixing and particle sorting performed by acoustic radiation forces are exploited in this thesis. Two different platforms are designed, manufactured and evaluated.

    List of papers
    1. An Evaluation of the Temperature Increase from PZT Micro-Transducers for Acoustic Trapping
    Open this publication in new window or tab >>An Evaluation of the Temperature Increase from PZT Micro-Transducers for Acoustic Trapping
    Show others...
    2005 (English)In: 2005 IEEE Ultrasonics Symposium, 2005, p. 1614-1617Conference paper, Published paper (Refereed)
    Identifiers
    urn:nbn:se:uu:diva-100674 (URN)0-7803-9382-1 (ISBN)
    Available from: 2009-04-06 Created: 2009-04-05 Last updated: 2009-04-06Bibliographically approved
    2. Noninvasive acoustic cell trapping in a microfluidic perfusion system for online bioassays
    Open this publication in new window or tab >>Noninvasive acoustic cell trapping in a microfluidic perfusion system for online bioassays
    Show others...
    2007 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 79, no 7, p. 2984-2991Article in journal (Refereed) Published
    Abstract [en]

    Techniques for manipulating, separating, and trapping particles and cells are highly desired in today's bioanalytical and biomedical field. The microfluidic chip-based acoustic noncontact trapping method earlier developed within the group now provides a flexible platform for performing cell- and particle-based assays in continuous flow microsystems. An acoustic standing wave is generated in etched glass channels (600x61 microm2) by miniature ultrasonic transducers (550x550x200 microm3). Particles or cells passing the transducer will be retained and levitated in the center of the channel without any contact with the channel walls. The maximum trapping force was calculated to be 430+/-135 pN by measuring the drag force exerted on a single particle levitated in the standing wave. The temperature increase in the channel was characterized by fluorescence measurements using rhodamine B, and levels of moderate temperature increase were noted. Neural stem cells were acoustically trapped and shown to be viable after 15 min. Further evidence of the mild cell handling conditions was demonstrated as yeast cells were successfully cultured for 6 h in the acoustic trap while being perfused by the cell medium at a flowrate of 1 microL/min. The acoustic microchip method facilitates trapping of single cells as well as larger cell clusters. The noncontact mode of cell handling is especially important when studies on nonadherent cells are performed, e.g., stem cells, yeast cells, or blood cells, as mechanical stress and surface interaction are minimized. The demonstrated acoustic trapping of cells and particles enables cell- or particle-based bioassays to be performed in a continuous flow format.

    Keywords
    Perfusion, Blood, Rhodamine, Fluorescence spectrometry, Transducer, Glass, Acoustic wave, Continuous flow method, Chemical analysis, Acoustic method, System on a chip, Biochemical analysis, Biological indicator, Bioassay, On line, Microfluidics, Trapping
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-100675 (URN)10.1021/ac061576v (DOI)000245304300047 ()17313183 (PubMedID)
    Available from: 2009-04-06 Created: 2009-04-05 Last updated: 2017-12-13Bibliographically approved
    3. Temperature control and resonance mode analysis of an acoustic trap for μTAS
    Open this publication in new window or tab >>Temperature control and resonance mode analysis of an acoustic trap for μTAS
    Show others...
    (English)Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-100678 (URN)
    Available from: 2009-04-08 Created: 2009-04-05 Last updated: 2009-04-08Bibliographically approved
    4.
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    5. On-chip fluorescence activated cell sorting by an integrated miniaturized ultrasonic transducer
    Open this publication in new window or tab >>On-chip fluorescence activated cell sorting by an integrated miniaturized ultrasonic transducer
    2009 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 81, no 13, p. 5188-5196Article in journal (Refereed) Published
    Abstract [en]

    An acoustic microfluidic system for miniaturized fluorescence-activated   cell sorting (mu FACS) is presented. By excitation of a miniaturized   piezoelectric transducer at 10 MHz in the microfluidic channel bottom, an acoustic standing wave is formed in the channel. The acoustic   radiation force acting on a density interface causes fluidic movement, and the particles or cells on either side of the fluid interface are displaced in a direction perpendicular to the standing wave direction. The small size of the transducer enables individual manipulation of   cells passing the transducer surface. At constant transducer activation   the system was shown to accomplish up to 700 mu m sideways displacement   of 10 mu m beads in a 1 mm wide channel. This is much larger than if   utilizing the acoustic radiation force acting directly on particles, where the limitation in maximum displacement is between a node and an antinode which at 10 MHz is 35 mu m. In the automatic sorting setup,   the system was demonstrated to successfully sort single cells of E-GFP expressing beta-cells.

    National Category
    Chemical Sciences Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-100677 (URN)10.1021/ac802681r (DOI)000267609500014 ()
    Available from: 2009-04-08 Created: 2009-04-05 Last updated: 2017-12-13Bibliographically approved
    6. Surface Acoustic Wave-induced particle sorting with node-position flexibility
    Open this publication in new window or tab >>Surface Acoustic Wave-induced particle sorting with node-position flexibility
    (English)In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-100812 (URN)
    Available from: 2009-04-07 Created: 2009-04-07 Last updated: 2017-12-13Bibliographically approved
    7. Surface Acoustic Wave-induced particle manipulation in a glass microfluidic channel
    Open this publication in new window or tab >>Surface Acoustic Wave-induced particle manipulation in a glass microfluidic channel
    (English)In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439Article in journal (Refereed) Submitted
    Keywords
    surface avoustic wave, manipulation, acoustic
    Identifiers
    urn:nbn:se:uu:diva-100904 (URN)
    Available from: 2009-04-10 Created: 2009-04-10 Last updated: 2017-12-13Bibliographically approved
    8. Acoustic manipulation of sub-micrometer particles by interface waves in microfluidic channels
    Open this publication in new window or tab >>Acoustic manipulation of sub-micrometer particles by interface waves in microfluidic channels
    Show others...
    (English)In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-100905 (URN)
    Available from: 2009-04-10 Created: 2009-04-10 Last updated: 2017-12-13Bibliographically approved
  • 15.
    Johansson, Linda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Mikrostrukturteknik.
    Nilsson, Mikael
    Lilliehorn, Tobias
    Almqvist, Monica
    Nilsson, Johan
    Laurell, Thomas
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Mikrostrukturteknik.
    An Evaluation of the Temperature Increase from PZT Micro-Transducers for Acoustic Trapping2005In: 2005 IEEE Ultrasonics Symposium, 2005, p. 1614-1617Conference paper (Refereed)
  • 16.
    Johansson, Linda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Enlund, Johannes
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Surface Acoustic Wave-induced particle sorting with node-position flexibilityIn: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189Article in journal (Refereed)
  • 17.
    Johansson, Linda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Evander, Mikael
    Lilliehorn, Tobias
    Almqvist, Monica
    Nilsson, Johan
    Laurell, Thomas
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Temperature control and resonance mode analysis of an acoustic trap for μTASArticle in journal (Refereed)
  • 18.
    Johansson, Linda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Thorslund, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    On-chip fluorescence activated cell sorting by an integrated miniaturized ultrasonic transducer2009In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 81, no 13, p. 5188-5196Article in journal (Refereed)
    Abstract [en]

    An acoustic microfluidic system for miniaturized fluorescence-activated   cell sorting (mu FACS) is presented. By excitation of a miniaturized   piezoelectric transducer at 10 MHz in the microfluidic channel bottom, an acoustic standing wave is formed in the channel. The acoustic   radiation force acting on a density interface causes fluidic movement, and the particles or cells on either side of the fluid interface are displaced in a direction perpendicular to the standing wave direction. The small size of the transducer enables individual manipulation of   cells passing the transducer surface. At constant transducer activation   the system was shown to accomplish up to 700 mu m sideways displacement   of 10 mu m beads in a 1 mm wide channel. This is much larger than if   utilizing the acoustic radiation force acting directly on particles, where the limitation in maximum displacement is between a node and an antinode which at 10 MHz is 35 mu m. In the automatic sorting setup,   the system was demonstrated to successfully sort single cells of E-GFP expressing beta-cells.

  • 19.
    Jonsson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Edqvist, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Almqvist, Monica
    Electrical Measurements, Lund University.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Simulation, manufacturing, and evaluation of a sonar for a miniaturized submersible explorer2010In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 57, no 2, p. 490-495Article in journal (Refereed)
    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.

  • 20.
    Lehto, Marcus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Division for Electricity and Lightning Research.
    Bodén, Roger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Simu, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Schweitz, Jan-Åke
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    A polymeric paraffin microactuator2008In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 17, no 5, p. 1172-1177Article in journal (Refereed)
    Abstract [en]

    Paraffin wax is a promising material in microactuators not only because of its ability of producing large displacements and high forces at the same time but also because of the variety of manufacturing techniques available. In this paper, a simple actuator based on paraffin wax as the active material is fabricated and tested. Ultraviolet-curable epoxy is used in a technique combining simultaneous moulding and liquid-phase photopolymerization in a single-process step to build the stiff part of the actuator body. A heater is integrated in the paraffin reservoir, and a polyimide tape is used as the deflecting membrane. Thermornechanical analysis of the paraffin wax shows that it exhibits a volume expansion of 10%, including phase transitions and linear expansion. As for the actuator, a stroke of 90 mu m is obtained for the unloaded device, whereas 37 mu m is recorded with a 0.5-N contact load at a driving voltage of 0.71 V and a frequency of 1/32 Hz. The actuator can be used in microsystems, where both large strokes and forces are needed. The low-cost materials and low driving voltage also makes it suitable for disposable systems.

  • 21.
    Lindeberg, Mikael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Yousef, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Rödjegård, Henrik
    Martin, Hans
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    A PCB-like Process for Vertically Configured Thermopiles2008In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 18, no 6, p. 065021-Article in journal (Refereed)
    Abstract [en]

    Thermopiles are important components in infrared thermal detectors, thermoelectric generators and thermoelectric coolers. We present a thermopile structure with up to 224 vertically arranged thermocouple legs in a polyimide flex material. The thermopile is optimized for infrared thermal radiation detection and is fabricated using printed circuit board-like (PCB-like) processing. Each thermoelectric leg consists of a bundle of a few hundred sub-micrometre-sized strands of either antimony or nickel. These metal wire bundles were achieved by employing ion track technology on the polyimide foil, resulting in a porous dielectric material. Electrochemical methods were used to grow the thermoelectric materials in the pores. The plating mask was produced in a laminated dry photoresist. A small metal cross section, 20 mu m(2) (1 vol%), ensured a low heat exchange between the two surfaces of the flex. The typical resistance per thermocouple was 34 Omega. A responsivity to irradiance of 4.3 V mm(2) W(-1) was measured when heating with a white light source (irradiance 1 mW mm(-2)).

  • 22.
    Nguyen, Hugo
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Jonsson, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Edqvist, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Sundqvist, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    A heavily miniaturized submersible: a terrestrial kickoff2008In: Proceedings of ASTRA 2008, 2008, p. 1-9Conference paper (Refereed)
    Abstract [en]

    The vision of exploring extraterrestrial water findings employing a remotely operated submersible, as proposed by JPL/NASA for the investigation of the possible ocean underneath the frozen crust of Jupiter’s moon Europa, is now taking a step further into fulfilment. The Ångström Space Technology Centre has developed a sophisticated vehicle concept based on microtechnology for most of the navigational systems and payload systems. This enables a high function density, and a compact vehicle with a diameter of 50 mm and length of 200 mm, i.e. an overall size allowing the vehicle to be deployed through a borehole like that typical for arctic drilling.

    Here, the system architecture of the vehicle complying with the requirements on manoeuvrability, operational functions, and mission objectives is presented. In short, the vehicle in the first version will operate in deep and narrow waters, and will be equipped with a camera, sonar imaging system, an electronic tongue for chemical sampling, and a Conductivity-Temperature-Depth (CTD) sensor. Although the vehicle will be given certain autonomy in later versions, the first edition will rely on remote manual guidance. Commands for this, as well as power download, and data upload will be communicated through an optic fibre.

    The objective of this contribution is to present, for the first time, the status of the project including, briefly, the first results from miniaturized sonar, the vehicle bus design, and the design, realization and testing of the propulsion and attitude control systems differing in manoeuvrability, weight/volume, redundancy and efficiency.

  • 23.
    Ogden, Sam
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Cheng, Shi
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microwave and Terahertz Technology.
    Öjefors, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microwave and Terahertz Technology.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microwave and Terahertz Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Fabrication of wireless sensor flip-up antennas2008In: Micro System Workshop MSW08, 2008, p. 61-Conference paper (Refereed)
  • 24. Ohgai, T.
    et al.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Spohr, R.
    Neumann, R.
    Electrodeposition of cobalt based ferro-magnetic metal nanowires in polycarbonate films with cylindrical nanochannels fabricated by heavy-ion-track etching2008In: Journal of Applied Electrochemistry, ISSN 0021-891X, E-ISSN 1572-8838, Vol. 38, no 5, p. 713-719Article in journal (Refereed)
    Abstract [en]

    Polycarbonate films of thickness 30 mu m were irradiated with heavy ions by applying a flux of 10(8) ions cm(-2) to produce straight tracks perpendicular to the film surface. The tracks were preferentially etched in 6 M aqueous solution of sodium hydroxide to prepare cylindrical nanochannels. The channel diameters were tuned between 200 and 600 nm by varying the etching time. Co81Cu19 alloy nanowires were electrodeposited potentiostatically, while Co/Cu multilayered nanowires, consisting of alternating Co and Cu layers with thickness 10 nm, were synthesized by means of a pulse plating technique in channels of length 30 mu m and diameter 200 nm. Co81Cu19 alloy nanowires showed an anisotropic magnetoresistance effect of 0.6%, and the giant magnetoresistance of Co/Cu multilayered nanowires reached up to 8.0%.

  • 25. Ordeig, Olga
    et al.
    Godino, Neus
    del Campo, Javier
    Muñoz, Francesc Xavier
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
    On-Chip Electric Field Driven Electrochemical Detection Using a Poly(dimethylsiloxane) Microchannel with Gold Microband Electrodes2008In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 80, no 10, p. 3622-3632Article in journal (Refereed)
    Abstract [en]

    An external electric field driven in-channel detection technique for on-chip electrochemical detection in micro fabricated devices is described based on a microfluidic system containing an array of 20 microband electrodes. It is shown that an external electric field induces a potential difference between two gold microband electrodes in a poly(dimethylsiloxane) (PDMS) microchannel, and that this enables the electrochemical detection of electroactive species such as ascorbic acid and Fe(CN)64−. The results, which are supported by simulations of the behavior of the microband electrodes in the microfluidic system, show that the induced potential difference between the electrodes can be controlled by altering the external electric field or by using different microbands in the microband array. As the obtained currents depend on the concentrations of electroactive species in the flowing solution and the detection can be carried out anywhere within the channel without interference of the external electric field, the present approach significantly facilitates electrochemical detection in capillary electrophoresis. This approach consequently holds great promise for application in inexpensive portable chip-based capillary electrophoresis (CE) devices.

  • 26.
    Palmer, Kristoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Lotfi, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Kratz, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Thornell, Greger
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    A micromachined dual-axis actuator for Use in a miniaturized optical communication system2008In: Proceeding of the International Astronautical Congress, Sep 29 - Oct 3, Glasgow, Scotland, 2008Conference paper (Refereed)
    Abstract [en]

    A micromachined beam-steering device for use in a miniaturized free-space optical communication system is presented. This device is part of a communication system intended for microspacecraft flying in kilometer-sized formations. Central to it, is a laser-reflecting mirror tiltable in two orthogonal directions using electrothermal actuators based on heating of a polymer confined in silicon v-grooves. The device is fabricated using standard microstructure technology. Successful experiments show a maximum mechanical scan range of 19º in two orthogonal directions. The voltages applied are below 100 V, and the power consumption is less than 2.4 W. Thermal coupling between orthogonal joints has been investigated with infrared imaging. The overall results are very promising, and improvement in the design and fabrication can be suggested.

  • 27.
    Skupinski, Marek
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Johansson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Jarmar, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Razpet, Alenka
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Boman, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
    Possnert, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    Jensen, Jens
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    Carbon nanopillar array deposition on SiO2 by ion irradiation through a porous alumina template2007In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 82, no 3, p. 359-362Article in journal (Refereed)
    Abstract [en]

    A method for producing ordered carbon nanopillar arrays is presented. The method is based on ion irradiation through a small anodic porous alumina membrane, resulting in carbon deposition within the centers of the pores on a gold covered SiO2/Si substrate. Samples were irradiated by 4 MeV Cl2+ ions with fluences of . The combined use of pick’n place positioning of the small porous alumina templates and ion beam irradiation is well suited for post-processing on silicon based integrated circuits. It provides fast local deposition at low temperature of high-density ordered carbon nanopillar arrays in larger silicon based systems, e.g., for field emitting or biosensors applications.

  • 28.
    Snis, Niklas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Edqvist, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Simu, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Monolithic fabrication of multilayer P(VDF-TrFE) cantilevers2008In: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 144, no 2, p. 314-320Article in journal (Refereed)
    Abstract [en]

    When operating a piezoelectric actuator the use of multilayers has for a long time proven to be a good solution to maintain a high electric field at a reduced applied voltage. The piezoelectric copolymer polyvinylidene-trifluoroethylene P(VDF-TrFE) has rather low piezoelectric constant compared to piezoceramics but it can withstand much higher electric fields. As the copolymer can be spin coated the individual layer thickness of the multilayer can easily be reduced to a few m and rather large strains can be achieved at a moderate voltage. Here a monolithic fabrication technique for producing P(VDF-TrFE) actuators, without any lamination or adhesive layers, is presented. To fabricate the multilayer successive spin coating of the piezoelectric polymer polyvinylidene-trifluoroethylene P(VDF-TrFE) and electrode evaporation on a substrate was performed. Four different substrate materials were coated with a multilayer stack of 6 active P(VDF-TrFE) layers and 7 aluminum electrodes. The monolithic multilayer structures with patterned electrodes were diced by a cutting saw to produce unimorph cantilevers. No delamination or dissolution could be observed between adjacent copolymer layers. The cantilevers were evaluated in terms of static and resonant deflection and the Q-factor was estimated from the frequency spectra. A discussion regarding the influence of the Q-factor on the fabrication process tolerance is given. The different substrate materials used was stainless steel, flexible printed circuit board (FPC), polycarbonate and aluminum. The Q-factor varied from 30 for the polycarbonate to 83 for the stainless steel. These results provide guidelines for the material choices of a forthcoming locomotion module to be used in the 3 mm 3 mm 3 mm I-SWARM robots. The FPC substrate showed to have the best compatibility to the fabrication processes and the most suitable Q-value of 42. This together with the high deflections makes the FPC the preferred substrate materials the future actuators for the I-SWARM locomotion module. 2008 Elsevier B.V. All rights reserved.

  • 29. Svensk, O
    et al.
    Törmä, P T
    Suihkonen, S
    Ali, M
    Lipsanen, H
    Sopanen, M
    Jensen, Jens
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Reduced photoluminescence from InGaN/GaN multiple quantum well structures irradiated by low fluence high energy heavy ions2008In: Book of Abstracts, Phalaborwa, South Africa, 2008Conference paper (Refereed)
  • 30.
    Svensson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Micropumps for extreme pressures2009Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis was to improve a paraffin actuated micropump design, to be able to pump against extreme pressures (above 100 bar). This was accomplished by initially studying the membrane activation, using video capturing. The micropump has been improved to withstand pressures high enough, to enable use in an high-performance liquid chromatography (HPLC) system. The micropump has been shown to pump against back pressures up to 150 bar, with a positive net-flow. This should be compared with the previously recorded maximum back pressure of 50 bar. The pumping against high back pressures was possible due to an increased understanding of the sealing of the membranes. This resulted in a new design that was manufactured and characterised. Without clamping the pump was measured to manage back pressures of 10 bar, and then starting to leak in a bond at the flow channel. With supporting clamping, the managed back pressures increased ten folded.

    When measured on the different valves, pressure above 200 bar has been possible to withhold. Although the valves were below their maximum limit, the pressure was not possible to be further increased due to a limitation in the equipment, i.e. risk of damaging the connections. When examined after pressurised at extreme pressures (above 100 bar) several times, no signs of fatigue or damage of the membrane was seen.

    A new behaviour of the valves was discovered. Above certain pressures some designs self sealed, i.e. withholding the pressure after the voltage was turned off. For these valves the pressure had to be released by some other means.

  • 31.
    Ventsislav, Yantchev
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Enlund, Johannes
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    katardjiev, Ilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Johansson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Johansson, Linda
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology .
    Acoustic manipulation of sub-micrometer particles by interface waves in microfluidic channelsIn: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189Article in journal (Refereed)
  • 32.
    Wu, Zhigang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Fast microfluidic particle filtering by dean spreading2008In: International Conference on Miniaturized Systems for Chemistry and Life Sciences μTAS2008, 2008, p. 1441-1443Conference paper (Refereed)
  • 33.
    Wu, Zhigang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Microfluidic Hydrodynamic Cell Separation: A Review2009In: Micro and Nanosystems, ISSN 1876-4037, Vol. 1, no 3, p. 181-192Article in journal (Refereed)
    Abstract [en]

    Microfluidic continuous cell separation based on hydrodynamic interaction in a microfluidic channel has attracted attention because of its robustness, high throughput and cell viability. This paper systematically gives an overview on recent advances in hydrodynamic particle and cell separation in microfluidic devices. It presents the basic ideas and fluid mechanics for the hydrodynamic interaction of a particle in a microfluidic system. Secondly, different kinds of devices are introduced with detailed descriptions of their mechanisms, designs and performances. Finally, the review addresses some practical issues of microfluidic sorting devices for use in biological or medical studies.

  • 34.
    Wu, Zhigang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Microfluidics for hydrodynamics2008In: Micro System Workshop MSW08, 2008, p. 54-Conference paper (Refereed)
  • 35.
    Wu, Zhigang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Wicher, Grzegorz
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Svenningsen, Åsa Fex
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Microfluidic high viability neural cell separation using viscoelastically tuned hydrodynamic spreading2008In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 10, no 5, p. 631-638Article in journal (Refereed)
    Abstract [en]

    A high viability microfluidic cell separation technique of high throughput was demonstrated based on size difference continuous mode hydrodynamic spreading with viscoelastic tuning. Using water with fluorescent dye as sample fluid and in parallel introducing as elution a viscoelastic biocompatible polymer solution of alginic sodium, the spreading behavior was investigated at different polymer concentrations and flow rates. Particle separation was studied in the same detail for 9.9 mu m and 1.9 mu m latex beads. Using buffered aqueous solutions and further surface treatments to protect from cell adhesion, separation between neuron cells and glial cells from rat's spine cord was demonstrated and compared to the separation of latex particles of 20 and 4.6 mu m sizes. High relative viability (above 90%) of neural cells was demonstrated compared the reference cells of the same batch.

  • 36. Yamamoto, Daniel L.
    et al.
    Csikasz, Robert I.
    Li, Yu
    Sharma, Gunjana
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Karlsson, Roger
    Bengtsson, Tore
    Myotube formation on micro-patterned glass: Intracellular organization and protein distribution in C2C12 skeletal muscle cells2008In: Journal of Histochemistry and Cytochemistry, ISSN 0022-1554, E-ISSN 1551-5044, Vol. 56, no 10, p. 881-892Article in journal (Refereed)
    Abstract [en]

    Proliferation and fusion of myoblasts are needed for the generation and repair of multinucleated skeletal muscle fibers in vivo. Studies of myocyte differentiation, cell fusion, and muscle repair are limited by an appropriate in vitro muscle cell culture system. We developed a novel cell culture technique [two-dimensional muscle syncytia (2DMS) technique] that results in formation of myotubes, organized in parallel much like the arrangement in muscle tissue. This technique is based on UV lithography-produced micro-patterned glass on which conventionally cultured C2C12 myoblasts proliferate, align, and fuse to neatly arranged contractile myotubes in parallel arrays. Combining this technique with fluorescent microscopy, we observed alignment of actin filament bundles and a perinuclear distribution of glucose transporter 4 after myotube formation. Newly formed myotubes contained adjacently located MyoD-positive and MyoD-negative nuclei, suggesting fusion of MyoD-positive and MyoD-negative cells. In comparison, the closely related myogenic factor Myf5 did not exhibit this pattern of distribution. Furthermore, cytoplasmic patches of MyoD colocalized with bundles of filamentous actin near myotube nuclei. At later stages of differentiation, all nuclei in the myotubes were MyoD negative. The 2DMS system is thus a useful tool for studies on muscle alignment, differentiation, fusion, and subcellular protein localization.

  • 37.
    Yousef, Hanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Lindeberg, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Plated Through-Hole Vias in a Porous Polyimide Foil for Flexible Printed Circuit Boards2008In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 18, no 1, p. 017001-Article in journal (Refereed)
    Abstract [en]

    A fabrication process for high aspect ratio plated through-hole vias is presented for flexibleprinted circuit boards. A 75 μm thick porous Kapton foil that allows direct definition of highaspect ratio through-hole vias by dry photoresist film lithography and electrodeposition ispresented. Pretreatment with swift heavy ion irradiation and wet etching define the poredensity and porosity of the foil, similar to ion-track-etched filter membranes. Thin filmmetallization of a seed layer and lithography of a laminated dry photoresist film define the viasizes and positions. Subsequent through-hole electrodeposition produces vias consisting ofmultiple wires, where each open pore defines one wire. The via geometries are characterizedby scanning electron microscopy. The electrical properties of the vias are characterized byresistance measurements. Vias with an aspect ratio over 2 and a side length of 33 μm showhigh yield with low resistance and low variation in resistance.

  • 38.
    Yousef, Hanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Mikael, Lindeberg
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Vertical Thermopiles Embedded in a Polyimide-Based Flexible Circuit Board2007In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 16, no 6, p. 1341-1348Article in journal (Refereed)
    Abstract [en]

    A fabrication process for vertical thermopiles embedded in a 75-mu m-thick polyimide foil has been developed for flexible printed circuit boards (flex PCBs). The vertical connections consist of electrodeposited antimony- and nickel-plated through-hole vias. The plated through-hole vias consist of multiple wires, with a total metal content that is 1% of the total via volume. The via fabrication technique is similar to standard flex PCB wet etch and metallization processes. The main difference is that the foils are pretreated with ion irradiation to induce highly selective vertical etch rates. The thermopiles were characterized by measuring their voltage response to an applied temperature difference across the foil thickness.

  • 39.
    Yousef, Hanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Lindeberg, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Micro Structural Technology.
    Ion Track Enabled Multiple Wire Microvia Interconnects in Printed Circuit Boards2008In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, ISSN 0168-583X, E-ISSN 1872-9584, Vol. 266, no 8, p. 1659-1665Article in journal (Refereed)
    Abstract [en]

    As the call for higher wiring density in packaging and vertical microvia interconnections (microvias) rapidly evolves, the need for smaller lateral dimensions in printed circuit boards (PCB) microvias must be met. The ion track lithography described in this paper allows for high throughput micromachining of small, deep, vertical microvias in flexible PCB and all-polymer laminates.

    Ion track lithography makes use of swift heavy ion irradiation to enhance the selectivity and directionality of chemical etching. Within the areas exposed to the ion irradiation, small sub-micron pores (capillaries) are created, one for every ion. If etching is prolonged, the pores become merged. Electrodeposition from a metallic seed layer is used to fill these structures with metal. The lithography masks define either the areas where the ion tracks are developed or where the tracks are metallized. The smallest achievable size of the microvias is only limited by the resolution of the mask; microvias below 10 μm in diameter can also be achieved also in thick polyimide foils.

    Since each impinging ion forms one track, the foil’s porosity can be controlled by adjusting the irradiation dose, as well as by etching the pores to a suitable size. Depending on the porosity and material, the resultant metallized microvia consists of either individual or interlaced wires (like strands in a bundle wire), or is a solid. As an individual sub-micron wire may have an aspect ratio of several hundreds, this allows for the fabrication of truly vertical microvia structures, allowing ultra-high density microvia batch production.

    Demonstrator microstructures with highly vertical microvias have been fabricated in foils up to 125 μm thickness. Several components integrated in flexible PCB have been presented by us, e.g. magnetoresistive sensors, thermopile IR-sensors and microwave components like inductor elements.