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  • 1.
    Abermann, S.
    et al.
    Institute of Solid State Electronics, Vienna University of Technology.
    Efavi, J. K.
    Sjöblom, Gustaf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lemme, M. C.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Bertagnolli, E.
    Institute of Solid State Electronics, Vienna University of Technology.
    Impact of Al-, Ni-, TiN-, and Mo-metal gates on MOCVD-grown HfO2 and ZrO2 high-k dielectrics2007In: Microelectronics and reliability, ISSN 0026-2714, E-ISSN 1872-941X, Vol. 47, no 4-5, p. 536-539Article in journal (Refereed)
    Abstract [en]

    In this work we compare the impacts of nickel (Ni), titanium-nitride (TiN), molybdenum (Mo), and aluminium (Al), gates on MOS capacitors incorporating HfO2- or ZrO2-dielectrics. The primary focus lies on interface trapping, oxide charging, and thermodynamical stability during different annealing steps of these gate stacks. Whereas Ni, Mo, and especially TiN are investigated as most promising candidates for future CMOS devices, Al acted as reference gate material to benchmark the parameters. Post-metallization annealing of both, TiN- and Mo-stacks, resulted in very promising electrical characteristics. However, gate stacks annealed at temperatures of 800 °C or 950 °C show thermodynamic instability and related undesirable high leakage currents.

  • 2.
    Abermann, S.
    et al.
    Institute for Solid State Electronics, Vienna University of Technology.
    Efavi, J. K.
    Advanced Microelectronic Center, Aachen.
    Sjöblom, Gustaf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lemme, M. C.
    Advanced Microelectronic Center, Aachen.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Bertagnolli, E.
    Institute for Solid State Electronics, Vienna University of Technology.
    Processing and evaluation of metal gate/high-k/Si capacitors incorporating Al, Ni, TiN, and Mo as metal gate, and ZrO2 and HfO2 as high-k dielectric2007In: Microelectronic Engineering, ISSN 0167-9317, E-ISSN 1873-5568, Vol. 84, no 5-8, p. 1635-1638Article in journal (Refereed)
    Abstract [en]

    We evaluate various metal gate/high-k/Si capacitors by their resulting electrical characteristics. Therefore, we process MOS gate stacks incorporating aluminium (Al), nickel (Ni), titanium-nitride (TiN), and molybdenum (Mo) as the gate material, and metal organic chemical vapour deposited (MOCVD) ZrO2 and HfO2 as the gate dielectric, respectively. The influence of the processing sequence - especially of the thermal annealing treatment - on the electrical characteristics of the various gate stacks is being investigated. Whereas post metallization annealing in forming gas atmosphere improves capacitance-voltage behaviour (due to reduced interface-, and oxide charge density), current-voltage characteristics degrade due to a higher leakage current after thermal treatment at higher temperatures. The Flatband-voltage values for the TiN-, Mo-, and Ni-capacitors indicate mid-gap pinning of the metal gates, however, Ni seems to be thermally unstable on ZrO2, at least within the process scheme we applied.

  • 3. Abermann, Stephan
    et al.
    Sjöblom, Gustaf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Efavi, Johnson
    Lemme, Max
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Bertagnolli, Emmerich
    Comparative Study On The Impact Of TiN and Mo Metal Gates ON MOCVD-Grown HfO2 and ZrO2 High-k Dielectrics For CMOS Technology2006In: Proceedings of 28th International Conference on the Physics of Semiconductors (ICPS) / [ed] Wolfgang Jantsch, Friedrich Schäffler, 2006Conference paper (Refereed)
  • 4.
    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)
  • 5.
    Aiempanakit, Montri
    et al.
    Linkoping University.
    Aijaz, Asim
    Linkoping University.
    Helmersson, Ulf
    Linkoping University.
    Kubart, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Hysteresis effect in reactive high power impulse magnetron sputtering of metal oxides2011Conference paper (Refereed)
    Abstract [en]

    In order to get high deposition rate and good film properties, the stabilization of the transition zone between the metallic and compound modes is beneficial. We have shown earlier that at least in some cases, HiPIMS can reduce hysteresis effect in reactive sputtering. In our previous work, mechanisms for the suppression/elimination of the hysteresis effect have been suggested. Reactive HiPIMS can suppress/eliminate the hysteresis effect in the range of optimum frequency [1] lead to the process stability during the deposition with high deposition rate. The mechanisms behind this optimum frequency may relate with high erosion rate during the pulse [2,3] and gas rarefaction effect in front of the target [4]. 

     

    In this contribution, reactive sputtering process using high power impulse magnetron sputtering (HiPIMS) has been studied with focus on the gas rarefaction. Through variations in the sputtering conditions such as pulse frequencies, peak powers, and target area, their effect on the shape of current waveforms have been analyzed. The current waveforms in compound mode are strongly affected. Our experiments show that the shape and amplitude of peak current cannot be explained by the change of the secondary electron yield due to target oxidation only. Reduced rarefaction in compound mode contributes to the observed very high peak current values.

  • 6. Anders, Andre
    et al.
    Lim, Sunnie H. N.
    Yu, Kin Man
    Andersson, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rosen, Johanna
    McFarland, Mike
    Brown, Jeff
    High quality ZnO:Al transparent conducting oxide films synthesized by pulsed filtered cathodic arc deposition2010In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 518, no 12, p. 3313-3319Article in journal (Refereed)
    Abstract [en]

    Aluminum-doped zinc oxide, ZnO:Al or AZO, is a well-known n-type transparent conducting oxide with great potential in a number of applications currently dominated by indium tin oxide. In this study, the optical and electrical properties of AZO thin films deposited on glass and silicon by pulsed filtered cathodic arc deposition are systematically studied. In contrast to magnetron sputtering, this technique does not produce energetic negative ions, and therefore ion damage can be minimized. The quality of the AZO films strongly depends on growth temperature while only marginal improvements are obtained with post-deposition annealing. The best films, grown at a temperature of about 200 degrees C, have resistivities in the low to mid 10(-4) Omega cm range with a transmittance better than 85% in the visible part of the spectrum. It is remarkable that relatively good films of small thickness (60 nm) can be fabricated using this method.

  • 7.
    Anderson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Development of Electroacoustic Sensors for Biomolecular Interaction Analysis2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biomolecular interaction analysis to determine the kinetics and affinity between interacting partners is important for the fundamental understanding of biology, as well as for the development of new pharmaceutical substances. A quartz crystal microbalance instrument suitable for kinetics and affinity analyses of interaction events was developed. The functionality of the sensor system was demonstrated by development of an assay for relative affinity determination of lectin-carbohydrate interactions.

    Sensor surfaces allowing for effective immobilization of one interacting partner is a key functionality of a biosensor. Here, three different surfaces and immobilization methods were studied. First, optimized preparation conditions for sensor surfaces based on carboxyl-terminated self assembled monolayers were developed and were demonstrated to provide highly functional biosensor surfaces with low non-specific binding. Second, a method allowing for immobilization of very acidic biomolecules based on the use of an electric field was developed and evaluated. The electric field made it possible to immobilize the highly acidic C-peptide on a carboxylated surface. Third, a method for antibody immobilization on a carboxyl surface was optimized and the influence of immobilization pH on the immobilization level and antigen binding capacity was thoroughly assessed. The method showed high reproducibility for a set of antibodies and allowed for antibody immobilization also at low pH.

    Three broadly different strategies to increase the sensitivity of electroacoustic sensors were explored. A QCM sensor with small resonator electrodes and reduced flow cell dimensions was demonstrated to improve the mass transport rate to the sensor surface. The use of polymers on QCM sensor surfaces to enhance the sensor response was shown to increase the response of an antibody-antigen model system more than ten-fold. Moreover, the application of high frequency thin film bulk acoustic resonators for biosensing was evaluated with respect to sensing range from the surface. The linear detection range of the thin film resonator was determined to be more than sufficient for biosensor applications involving, for instance, antibody-antigen interactions. Finally, a setup for combined frequency and resistance measurements was developed and was found to provide time resolved data suitable for kinetics determination.

    List of papers
    1. Study of real-time lectin-carbohydrate interactions on the surface of a quartz crystal microbalance
    Open this publication in new window or tab >>Study of real-time lectin-carbohydrate interactions on the surface of a quartz crystal microbalance
    2005 (English)In: Biosensors & Bioelectronics, Vol. 21, p. 60-66Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-26504 (URN)
    Available from: 2007-02-19 Created: 2007-02-19 Last updated: 2011-01-12
    2. Esterification of Self-Assembled Carboxylic-Acid-Terminated Thiol Monolayers in Acid Environment: A Time-Dependent Study
    Open this publication in new window or tab >>Esterification of Self-Assembled Carboxylic-Acid-Terminated Thiol Monolayers in Acid Environment: A Time-Dependent Study
    Show others...
    2010 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 26, no 2, p. 821-829Article in journal (Refereed) Published
    Abstract [en]

    This contribution reports on the influence of acids oil the quality of carboxylic-acid-terminated self-assembled monolayers (SAMs) on gold prepared from ethanolic solution of HS-(CH2)(15)-COOH and HS-(CH2)(11)CONH-(EG)(6)CH2-COOH. Null ellipsometry, contact angle goniometry, and infrared reflection-absorption spectroscopy are used to monitor the physical and chemical changes occurring within the SAMs upon acid post treatment; after incubation with acids present in the solution: and after incubation in aged acid containing solutions. The presence of acid has a positive effect oil the crystallinity, packing, and orientation Of the Supporting alkyl and ethylene glycol Subunits of the SAM. Our Studies also confirm previous findings stating that the carboxylic groups are rapidly converted into ethyl ester groups in the presence of hydrochloric acid in the incubation solution. It is also evident that the conversion occurs in the presence of the weaker acid, acetic acid, although at a much slower rate than that for hydrochloric acid. This is a new observation that has not been reported on before. The physical and chemical characterization is also complemented with a functional bioaffinity study. The functional evaluation revealed that the present model system was surprisingly insensitive to the degree of esterification of the carboxylic acid groups, but that 4 weeks of storage of the two investigated thiols in hydrochloric acid containing ethanol resulted in SAMs that were completely inactive with respect to immobilization and subsequent binding of the antigen. It was encouraging to note that the nonspecific binding of both antigen and antibody was extremely low oil the two SAMs, regardless of the relative amount of ethyl esters on the surface.

    National Category
    Engineering and Technology Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-137945 (URN)10.1021/la902255j (DOI)000273403400029 ()
    Available from: 2010-12-16 Created: 2010-12-16 Last updated: 2022-01-28Bibliographically approved
    3. Electroimmobilization of proinsulin C-peptide to a quartz crystal microbalance sensor chip for protein affinity purification
    Open this publication in new window or tab >>Electroimmobilization of proinsulin C-peptide to a quartz crystal microbalance sensor chip for protein affinity purification
    Show others...
    2005 (English)In: Anal Biochem, Vol. 341, no 1, p. 89-93Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-26506 (URN)
    Available from: 2007-02-19 Created: 2007-02-19 Last updated: 2011-01-12
    4. Optimizing immobilization on two-dimensional carboxyl surface: pH dependence of antibody orientation and antigen binding capacity
    Open this publication in new window or tab >>Optimizing immobilization on two-dimensional carboxyl surface: pH dependence of antibody orientation and antigen binding capacity
    Show others...
    2010 (English)In: Analytical Biochemistry, ISSN 0003-2697, E-ISSN 1096-0309, Vol. 398, no 2, p. 161-168Article in journal (Refereed) Published
    Abstract [en]

    The performance of immunosensors is highly dependent on the amount of immobilized antibodies and their remaining antigen binding capacity. In this work, a method for immobilization of antibodies on a two dimensional carboxyl surface has been optimized using quartz crystal microbalance biosensors. We have shown that successful immobilization is highly dependent on surface pKa, antibody pI and pH of immobilization buffer. By use of EDC/sulfo-NHS activation reagents, the effect of the intrinsic surface pKa is avoided and immobilization also at very low pH has been made possible which is of importance for immobilization of acidic proteins. Generic immobilization conditions were demonstrated on a panel of antibodies which resulted in an average coefficient of variation of 4% for the immobilization of these antibodies.

    Antigen binding capacity as a function of immobilization pH was studied. In most cases the antigen binding capacity followed the immobilization response. However, the antigen to antibody binding ratio differed between the antibodies investigated, and for one of the antibodies, the antigen binding capacity was significantly lower than expected from immobilization in a certain pH range. Tests with anti-Fc and anti-Fab antibodies on different antibody surfaces showed that the orientation of the antibodies on the surface had a profound effect on the antigen binding capacity of the immobilized antibodies.

    Keywords
    antibody, orientation, biosensor, immobilization, sensor surface, QCM
    National Category
    Other Industrial Biotechnology Analytical Chemistry
    Research subject
    Surface Biotechnology
    Identifiers
    urn:nbn:se:uu:diva-107233 (URN)10.1016/j.ab.2009.11.038 (DOI)000274615100003 ()19962366 (PubMedID)
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    5. Quartz crystal microbalance sensor design: I. Experimental study of sensor response and performance
    Open this publication in new window or tab >>Quartz crystal microbalance sensor design: I. Experimental study of sensor response and performance
    Show others...
    2007 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 123, no 1, p. 27-34Article in journal (Refereed) Published
    Abstract [en]

    This paper investigates a novel quartz crystal microbalance (QCM) biosensor with a small and rectangular flow cell along with a correspondingly shaped crystal electrode. The sensor was evaluated with impedance analysis and compared to standard circular sensor crystals and sensor crystals with small circular electrodes. Comparative QCM measurements on an antibody–antigen interaction system were carried out on the rectangular and standard circular sensor systems. Impedance analysis and subsequent data extraction of the three different sensor crystals showed that the smaller sensors had significantly higher Q-values in air, but that liquid load on the electrodes lowered the Q-values radically for all crystals. Under liquid load, Q-values for the standard circular and the rectangular sensors were similar whereas the Q-value for the small circular sensor was 50% higher. QCM experiments showed that the QCM system with rectangular crystal electrodes was fully functional in a liquid environment. The rectangular system showed higher and more rapid responses for series of antibody injections, albeit at a higher noise level than the standard system. The study elucidates a significant potential for improvement of sensor performance by optimising the sensor electrode size and shape together with the flow cell geometry.

    Keywords
    QCM, Biosensor, Sensitivity, Mass transport, Protein interactions
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-94271 (URN)10.1016/j.snb.2006.07.027 (DOI)000246171200006 ()
    Available from: 2006-04-07 Created: 2006-04-07 Last updated: 2017-12-14Bibliographically approved
    6. Quartz crystal microbalance biosensor design: II. Simulation of sample transport
    Open this publication in new window or tab >>Quartz crystal microbalance biosensor design: II. Simulation of sample transport
    2007 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 123, no 1, p. 21-26Article in journal (Refereed) Published
    Abstract [en]

    The influence of flow cell geometry on sample dispersion in a quartz crystal microbalance (QCM) biosensor system was investigated. A circular and a rectangular flow cell and corresponding sensor electrodes were studied experimentally and modelled using a coupled Navier-Stokes and convection-diffusion model. Finite element simulations showed that dispersion phenomena in a flow cell can be significantly reduced with the rectangular flow cell compared to a circular system. Experimental results from measurement of the time-dependent viscosity change of a model sample indicate that the sample delivery system has a predominant effect on the dispersion of the whole sensor system. Consequently, improvement of the sensor flow cell should be accompanied with improvement of the sample delivery system. With reference to kinetic studies of biological interactions, the current dispersion should have little effect on the results for studies of interaction pairs with relatively slow to normal binding rates such as antibody-antigen interactions. Incentive for further development of the flow cell and sample delivery system exists primarily for applications with high reaction rates such as for certain receptor ligand interactions.

     

    Keywords
    QCM, Simulation, FEM, Navier–Stokes, Convection and diffusion, Microfluidic
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-94272 (URN)10.1016/j.snb.2006.07.028 (DOI)000246171200005 ()
    Available from: 2006-04-07 Created: 2006-04-07 Last updated: 2022-01-28Bibliographically approved
    7. Surface-Confined Photopolymerization of pH-Responsive Acrylamide/Acrylate Brushes on Polymer Thin Films
    Open this publication in new window or tab >>Surface-Confined Photopolymerization of pH-Responsive Acrylamide/Acrylate Brushes on Polymer Thin Films
    Show others...
    2008 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 24, no 14, p. 7559-7564Article in journal (Refereed) Published
    Abstract [en]

    Dynamic acrylamide/acrylate polymeric brushes were synthesized at gold-plated quartz crystal surfaces. The crystals were initially coated with polystyrene-type thin films, derivatized with photolabile iniferter groups, and subsequently subjected to photoinitiated polymerization in acrylamide/acrylate monomer feeds. This surface-confined polymerizationmethod enabled direct photocontrol over the polymerization, as followed by increased frequency responses of the crystal oscillations in a quartz crystal microbalance (QCM). The produced polymer layers were also found to be highlysensitive to external acid/base stimuli. Large oscillation frequency shifts were detected when the brushes were exposedto buffer solutions of different pH. The dynamic behavior of the resulting polymeric brushes was evaluated, and theextent of expansion and contraction of the films was monitored by the QCM setup in situ in real time. The resultingresponses were rapid, and the effects were fully reversible. Low pH resulted in full contractions of the films, whereashigher pH yielded maximal expansion in order to minimize repulsion around the charged acrylate centers. The surfacesalso proved to be very robust because the responsiveness was reproducible over many cycles of repeated expansionand contraction. Using ellipsometry, copolymer layers were estimated to be ∼220 nm in a collapsed state and ∼340nm in the expanded state, effectively increasing the thickness of the film by 55%.

    Keywords
    Surface grafting, polymer brushes, hydrogels, sensor surfaces, transfer radical polymerization
    National Category
    Polymer Chemistry Physical Chemistry Engineering and Technology
    Research subject
    Surface Biotechnology
    Identifiers
    urn:nbn:se:uu:diva-107234 (URN)10.1021/la800700h (DOI)000257468300072 ()18563922 (PubMedID)
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    8. Signal Enhancement in Ligand-Receptor Interactions using Dynamic Polymers at Quartz Crystal Microbalance Surfaces
    Open this publication in new window or tab >>Signal Enhancement in Ligand-Receptor Interactions using Dynamic Polymers at Quartz Crystal Microbalance Surfaces
    Show others...
    2016 (English)In: The Analyst, ISSN 0003-2654, E-ISSN 1364-5528, Vol. 141, no 13, p. 3993-3996Article in journal (Refereed) Published
    Abstract [en]

    The potential for signal amplification on QCM sensors by use of in situ polymerized poly(acrylic acid) brushes has been studied. A biotin derivative was immobilized on these surfaces and the interaction with anti-biotin Fabs was evaluated. Interaction data was found to be specific for the studied binding events, and the level of non-specific binding was shown to be low. The surface was proven to be suitable for regeneration, of importance for biomolecular interaction analysis and repetitive immunoassays.

    For comparison, the same interaction system was tested using commercial sensor surfaces with carboxylated self-assembled monolayers. The poly(acrylic acid) surface showed a dramatic increase in signal response with more than ten times the signal of the carboxylated self-assembled monolayer surface. Thus, the present study shows that polymers can be successfully applied to amplify responses on QCM sensors, valuable for studies of interactions between receptors and low molecular weight compounds.

    Keywords
    dynamic chemistry, quartz crystal microbalance, iniferter, photopolymerization, biosensor, interaction
    National Category
    Polymer Chemistry Engineering and Technology
    Research subject
    Surface Biotechnology
    Identifiers
    urn:nbn:se:uu:diva-107252 (URN)10.1039/c6an00735j (DOI)000378942300006 ()27196531 (PubMedID)
    External cooperation:
    Funder
    Swedish Research Council
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    9. On the applicability of high frequency acoustic shear mode biosensing in view of thickness limitations set by the film resonance
    Open this publication in new window or tab >>On the applicability of high frequency acoustic shear mode biosensing in view of thickness limitations set by the film resonance
    Show others...
    2009 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 24, no 11, p. 3387-3390Article in journal (Refereed) Published
    Abstract [en]

    The IC-compatible thin film bulk acoustic resonator (FBAR) technology has made it possible to move the thickness excited shear mode sensing of biological layers into a new sensing regime using substantially higher operation frequencies than the conventionally used Quartz Crystal Microbalance (QCM). The limitations of the linear range set by the film resonance using viscoelastic protein films are here for the first time addressed specifically for FBARs operating at 700MHz up to 1.5GHz. Two types of protein multilayer sensing were employed; one utilizing alternating layers of Streptavidin and Biotinated BSA and the other using stepwise cross-linking of fibrinogen with EDC/NHS activation of its carboxyl groups. In both cases the number of protein layers within the linear regime is well above the number of protein layers usually used in biosensor applications, further verifying the applicability of the FBAR as a biosensor. Theoretical calculations are also presented using well established physical models to illustrate the expected behavior of the FBAR sensor, in view of both the frequency and the dissipation shifts.

    Keywords
    Shear mode electroacoustic sensing, Streptavidin–biotinated BSA, Fibrinogen, High frequency, Thin film bulk acoustic resonator (FBAR)
    National Category
    Engineering and Technology
    Research subject
    Electronics
    Identifiers
    urn:nbn:se:uu:diva-89406 (URN)10.1016/j.bios.2009.04.021 (DOI)000267577900035 ()
    Available from: 2009-02-12 Created: 2009-02-12 Last updated: 2018-06-26Bibliographically approved
    10. Systematic investigation of biomolecular interactions using combined frequency and motional resistance measurements
    Open this publication in new window or tab >>Systematic investigation of biomolecular interactions using combined frequency and motional resistance measurements
    Show others...
    2011 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 153, no 1, p. 135-144Article in journal (Refereed) Published
    Abstract [en]

    The resonance frequency of acoustic biosensors is today used as a label-free technique for detecting mass changes on sensor surfaces. In combination with an appropriate continuous flow system it has earlier been used for affinity and kinetic rate determination. Here, we assess the potential of a modified acoustic biosensor, monitoring also the real-time dissipation through the resistance of the sensor, to obtain additional kinetic information related to the structure and conformation of the molecules on the surface. Actual interaction studies, including an attempt to determine avidity, are presented along with thorough verification of the experimental setup utilizing true viscous load exposure together with protein and DNA immobilizations. True viscous loads show a linear relationship between resistance and frequency as expected. However, in the interaction studies between antibodies and proteins, as well as in the immobilization of DNA and proteins, higher surface concentrations of interacting molecules led to a decrease (i.e. deviation from the linear trend) in the differential resistance to frequency ratio. This is interpreted as increased surface rigidity at higher surface concentrations of immobilized molecules. Consequently, studies that aim at obtaining biological binding information, such as avidity, from real-time resistance and dissipation data should be conducted at low surface concentrations. In addition, the differential resistance to frequency relationship was found to be highly dependent on the rigidity of the preceding layer(s) of immobilized molecules. This dependence can be utilized to obtain a higher signal-to-noise ratio for resistance measurement by using low surface densities of immobilized interaction partners.

    Keywords
    biosensor, interaction analysis, QCM, dissipation, motional resistance, kinetics
    National Category
    Analytical Chemistry Other Industrial Biotechnology
    Research subject
    Analytical Chemistry; Engineering Science with specialization in Microsystems Technology; Engineering Science with specialization in Electronics
    Identifiers
    urn:nbn:se:uu:diva-107253 (URN)10.1016/j.snb.2010.10.019 (DOI)000289019300020 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2018-06-26Bibliographically approved
    Download full text (pdf)
    FULLTEXT01
  • 8.
    Anderson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Jönsson, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lindberg, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Aastrup, Teodor
    Quartz crystal microbalance sensor design: I. Experimental study of sensor response and performance2007In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 123, no 1, p. 27-34Article in journal (Refereed)
    Abstract [en]

    This paper investigates a novel quartz crystal microbalance (QCM) biosensor with a small and rectangular flow cell along with a correspondingly shaped crystal electrode. The sensor was evaluated with impedance analysis and compared to standard circular sensor crystals and sensor crystals with small circular electrodes. Comparative QCM measurements on an antibody–antigen interaction system were carried out on the rectangular and standard circular sensor systems. Impedance analysis and subsequent data extraction of the three different sensor crystals showed that the smaller sensors had significantly higher Q-values in air, but that liquid load on the electrodes lowered the Q-values radically for all crystals. Under liquid load, Q-values for the standard circular and the rectangular sensors were similar whereas the Q-value for the small circular sensor was 50% higher. QCM experiments showed that the QCM system with rectangular crystal electrodes was fully functional in a liquid environment. The rectangular system showed higher and more rapid responses for series of antibody injections, albeit at a higher noise level than the standard system. The study elucidates a significant potential for improvement of sensor performance by optimising the sensor electrode size and shape together with the flow cell geometry.

  • 9.
    Anderson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Wingqvist, Gunilla
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Weissbach, Thomas
    Attana AB, Stockholm.
    Wallinder, Daniel
    Attana AB, Stockholm.
    Katardjiev, Ilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Ingemarsson, Björn
    Attana AB, Stockholm.
    Systematic investigation of biomolecular interactions using combined frequency and motional resistance measurements2011In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 153, no 1, p. 135-144Article in journal (Refereed)
    Abstract [en]

    The resonance frequency of acoustic biosensors is today used as a label-free technique for detecting mass changes on sensor surfaces. In combination with an appropriate continuous flow system it has earlier been used for affinity and kinetic rate determination. Here, we assess the potential of a modified acoustic biosensor, monitoring also the real-time dissipation through the resistance of the sensor, to obtain additional kinetic information related to the structure and conformation of the molecules on the surface. Actual interaction studies, including an attempt to determine avidity, are presented along with thorough verification of the experimental setup utilizing true viscous load exposure together with protein and DNA immobilizations. True viscous loads show a linear relationship between resistance and frequency as expected. However, in the interaction studies between antibodies and proteins, as well as in the immobilization of DNA and proteins, higher surface concentrations of interacting molecules led to a decrease (i.e. deviation from the linear trend) in the differential resistance to frequency ratio. This is interpreted as increased surface rigidity at higher surface concentrations of immobilized molecules. Consequently, studies that aim at obtaining biological binding information, such as avidity, from real-time resistance and dissipation data should be conducted at low surface concentrations. In addition, the differential resistance to frequency relationship was found to be highly dependent on the rigidity of the preceding layer(s) of immobilized molecules. This dependence can be utilized to obtain a higher signal-to-noise ratio for resistance measurement by using low surface densities of immobilized interaction partners.

  • 10.
    Andersson, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Anders, Andre
    Plasma Applications Group, Lawrence Berkley National Laboratory.
    High rate copper deposition using gasless HiPIMS2010Conference paper (Refereed)
  • 11.
    Andersson, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Anders, Andre
    Lawrence Berkeley National Laboratory, USA.
    The deposition rate of copper in HiPIMS is reduced by the presence of sputter gas2010In: 1st internationall conference on HiPIMS, 6-7th of July 2010, Sheffield, UK, 2010Conference paper (Refereed)
  • 12.
    Anderås, Emil
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vallin, Örjan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    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.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Drift in thin film SOI piezoresistors2010In: Proc. of EUROSOI Workshop, 2010 Jan 25-27, Grenoble, France, 2010, p. 71-72Conference paper (Refereed)
  • 13.
    Anderås, Emil
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    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.
    Resistance Electric Field Dependence and Time Drift of Piezoresistive Single Crystalline Silicon Nanofilms2009In: Proceedings of Eurosensors May 2009, Procedia Chemistry vol 1 (1), 2009, p. 80-83Conference paper (Refereed)
  • 14.
    Ankarcrona, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    High Frequency Analysis of Silicon RF MOS Transistors2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today, the silicon technology is well established for RF-applications (f~1-100 GHz), with emphasis on the lower frequencies (f < 5 GHz). The field of RF power devices is extensive concerning materials and devices. One of the important RF-devices is the silicon LDMOS transistor. A large extent of the research presented in the thesis concerns studies of this device, which have resulted in increased understanding of the device behavior and improved performance. The thesis starts with a brief survey of the RF-field, including the LDMOS transistor, followed by a description of the methods used in the investigations; simulations, modeling and measurements. Specific results presented in the appended papers are also briefly summarized.

    A new concept for LDMOS transistors, which allows for both high frequency and high voltage operation, has been developed and characterized. World-record performance in terms of output power density was obtained: over 1 W/mm at 50 V and 3.2 GHz. Further understanding and improvements of the device are achieved using simulations and modeling. For determination of model parameters a new general parameter extraction technique was developed. The method has been successfully used for a large variety of high-frequency devices, and has been frequently used in the modeling work in this thesis.

    Important properties of RF-power devices are the device linearity and power efficiency. Extensive studies regarding the efficiency were conducted using numerical simulations and modeling of the off-state output resistance, which is correlated to the efficiency. The results show that significant improvements can be obtained for devices on both bulk- and SOI-substrates, using thin high-resistivity substrates and very low-resistivity SOI-substrates, respectively.

    Finally a new approach to drastically reduce substrate crosstalk by using very low-resistivity SOI substrate is proposed. Experimentally, a reduction of 20-40 dB was demonstrated in the GHz range compared to high-resistivity SOI substrate.

    List of papers
    1. Sub-Circuit Based SPICE Model for High Voltage LDMOS Transistors
    Open this publication in new window or tab >>Sub-Circuit Based SPICE Model for High Voltage LDMOS Transistors
    2002 (English)In: Physica Scripta, no T101, p. 7-9Article in journal (Refereed) Published
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Research subject
    Engineering Science with specialization in Electronics
    Identifiers
    urn:nbn:se:uu:diva-93398 (URN)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2012-09-26
    2. A General Small-Signal Series Impedance Extraction Technique
    Open this publication in new window or tab >>A General Small-Signal Series Impedance Extraction Technique
    2002 (English)In: IEEE Microwave and Wireless Components Letters, ISSN 1531-1309, E-ISSN 1558-1764, Vol. 12, no 7, p. 249-251Article in journal (Refereed) Published
    Abstract [en]

    A new technique for extracting the series inductances and resistances in a small-signal equivalent circuit is presented. The technique does not rely on approximation and should therefore be as accurate as the measured data. The technique can also be used to extract the intrinsic parameters if they are not easily achieved using other methods. The method is exemplified with a microwave LDMOS transistor

    Keywords
    S-parameters, microwave LDMOS transistor, parameter estimation, series inductances, series resistances, small-signal equivalent circuit, small-signal series impedance extraction technique
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-93400 (URN)10.1109/LMWC.2002.801134 (DOI)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2017-12-14Bibliographically approved
    3. Analysis and Design of a Low-Voltage High-Frequency LDMOS Transistor
    Open this publication in new window or tab >>Analysis and Design of a Low-Voltage High-Frequency LDMOS Transistor
    2002 (English)In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, Vol. 49, no 6, p. 976-980Article in journal (Refereed) Published
    Abstract [en]

    For a low voltage lateral double-diffused MOS (LDMOS) transistor, the output performance has been improved in terms of fMAX. This is done by decreasing the output capacitance and thus decreasing the total output conductance. Extraction of the model parameters has been made and the most efficient parameter to improve was identified and linked to a specific part of the transistor structure. Layout changes in the n-well/p-base region were done as the result of the model analyses and finally, the modified devices were processed. Measurements on the improved devices showed results that closely, matched the expected, and fMAX was increased with 30% and only a slight decrease in f T. Finally, the capacitance reduction in the n-well/p-base junction was measured by direct. measurements

    Keywords
    LV HF LDMOS transistor, S-parameter, current-voltage characteristics, equivalent circuits, layout changes, microwave FET, model parameters, n-well/p-base junction, output capacitance, output performance, small-signal parameters, total output conductance
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-93401 (URN)10.1109/TED.2002.1003715 (DOI)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2017-12-14
    4. Simulation and modeling of the substrate contribution to the output resistance for RF-LDMOS power transistors
    Open this publication in new window or tab >>Simulation and modeling of the substrate contribution to the output resistance for RF-LDMOS power transistors
    2004 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 48, no 5, p. 789-797Article in journal (Refereed) Published
    Abstract [en]

    High frequency substrate losses for RF MOSFETs are analyzed using numerical device simulation. The results show that losses in devices made on low resistivity substrate occur through the substrate while losses in devices made on high resistivity substrate in the high frequency region occur along the surface through the device (source–drain). An equivalent circuit model is developed which accurately describes the off-state losses. Based on the model significant improvements in terms of output resistance are demonstrated, using an improved device on high resistivity substrate.

    Keywords
    Substrate losses, Modeling, RF MOSFET, LDMOS
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-93402 (URN)10.1016/j.sse.2003.12.005 (DOI)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2017-12-14
    5. Improved Output Resistance in RF-power MOSFETs using Low Resistivity SOI Substrate
    Open this publication in new window or tab >>Improved Output Resistance in RF-power MOSFETs using Low Resistivity SOI Substrate
    Show others...
    (English)Manuscript (Other academic)
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-93403 (URN)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2015-07-21Bibliographically approved
    6. Low Resistivity SOI for Substrate Crosstalk Reduction
    Open this publication in new window or tab >>Low Resistivity SOI for Substrate Crosstalk Reduction
    2005 (English)In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, IEEE Trans on Electronic Devices, Vol. 52, no 8, p. 1920-1922Article in journal (Refereed) Published
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-93404 (URN)
    Available from: 2005-09-02 Created: 2005-09-02 Last updated: 2017-12-14Bibliographically approved
    7. 1 W/mm RF Power Denisty at 3.2 GHz for a Dual-Layer RESURF LDMOS Transistor
    Open this publication in new window or tab >>1 W/mm RF Power Denisty at 3.2 GHz for a Dual-Layer RESURF LDMOS Transistor
    Show others...
    2002 (English)In: IEEE Electron Device Letters, ISSN 0741-3106, Vol. 23, no 4, p. 206-208Article in journal (Refereed) Published
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-41678 (URN)10.1109/55.992840 (DOI)
    Available from: 2007-02-23 Created: 2007-02-23 Last updated: 2010-07-09Bibliographically approved
    Download full text (pdf)
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  • 15.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Analysis and improvments of high frequency substrate losses for RF MOSFETs2003In: Proceedings of IEEE SISPAD, 2003, p. 319-322Conference paper (Refereed)
  • 16.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Simulation and modeling of the substrate contribution to the output resistance for RF-LDMOS power transistors2004In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 48, no 5, p. 789-797Article in journal (Refereed)
    Abstract [en]

    High frequency substrate losses for RF MOSFETs are analyzed using numerical device simulation. The results show that losses in devices made on low resistivity substrate occur through the substrate while losses in devices made on high resistivity substrate in the high frequency region occur along the surface through the device (source–drain). An equivalent circuit model is developed which accurately describes the off-state losses. Based on the model significant improvements in terms of output resistance are demonstrated, using an improved device on high resistivity substrate.

  • 17.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Simulation and modeling of the substrate influence on the high frequency performance for RF LDMOS2003In: GHz2003 Symposium, Nov. 4-5, 2003Conference paper (Refereed)
  • 18.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Larsen, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low Resistivity SOI Substrates for Improved Efficiency of RF Power-MOSFETs2004In: Proc of NATO Advanced Research Workshop on SOI, Kiev 25-29 April: Science and Technology of SOI structures and devices operating in a harsh environment, 2004Conference paper (Other academic)
  • 19.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Larsen, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Improved Efficiency for RF Power-MOSFETs using Low Resistivity SOI Substrates2005In: Proceedings of GHz2005 Symposium, 2005, p. 135-138Conference paper (Refereed)
  • 20.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Larsen, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Improved Output Resistance in RF-power MOSFETs using Low Resistivity SOI SubstrateManuscript (Other academic)
  • 21.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Larsen, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low Resistivity SOI for Improved Efficiency of LDMOS2006In: Proceedings of EUROSOI Workshop, March, 2006, p. 69-70Conference paper (Refereed)
  • 22.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Analysis of crosstalk in SOI substrates2005In: Proceedings of GHz2005 Symposium, 2005, p. 131-134Conference paper (Refereed)
  • 23.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Crosstalk Reduction Using Low Resistivity SOI2005In: Proceedings of EUROSOI Workshop, 2005, p. 129-130Conference paper (Refereed)
  • 24.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Efficient Crosstalk Reduction Using Very Low Resistivity SOI Substrate2005In: Proceedings of 35th ESSDERC, 2005, p. 233-236Conference paper (Refereed)
  • 25.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    High Power Efficiency using Very Low Resistivity SOI2007Conference paper (Refereed)
  • 26.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low Resistivity SOI for Substrate Crosstalk Reduction2005In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, IEEE Trans on Electronic Devices, Vol. 52, no 8, p. 1920-1922Article in journal (Refereed)
  • 27.
    Ankarcrona, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Eklund, Klas-Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low Resistivity SOI for Substrate Crosstalk Reduction2005In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, Vol. 52, no 8, p. 1920-1922Article in journal (Refereed)
  • 28.
    Avramov, Ivan
    et al.
    Bulgarian Academy of Sciences.
    Arapan, Lilia
    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.
    Strashilov, Vesseline
    University of Sofia.
    Yantchev, Ventsislav
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    IC-compatible Power Oscillators Using Thin Film Plate Acoustic Resonator (FPAR)2009In: Proceedings 2009 IEEE International Ultrasonics Symposium, 2009Conference paper (Refereed)
    Abstract [en]

    In this study, two-port 880MHz FPAR devicesoperating on the lowest order fast symmetric Lamb wave mode(S0) in c-oriented AlN membranes on Si, were fabricated andsubsequently tested for their power handling capabilities in afeedback-loop power oscillator circuit. The S0 Lamb waves wereexcited and detected by a classical two-port resonator structure,as in Rayleigh SAW (RSAW) resonators. Incident power levels ofup to 24 dBm (250 mW) for the FPARs were provided by a high powersustaining amplifier in the loop. No measurable performance degradation was observed. The results from this study indicate that IC-compatible S0 FPAR devices can dissipate orders of magnitude higher RF-power levels than their RSAWcounterparts on quartz and are well suited for integrated microwave power oscillators with thermal noise floor (TNF) levelsbelow -175 dBc/Hz.

  • 29. Baránková, H.
    et al.
    Bárdoš, L.
    Gustavsson, L-E.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Electronics.
    High-rate hot hollow cathode arc deposition of chromium and chromium nitride films2004In: Surface and Coatings Technology, ISSN 0257-8972, Vol. 188-189, p. 703-707Article in journal (Refereed)
  • 30. Baránková, H.
    et al.
    Bárdoš, L.
    Gustavsson, L-E.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Electronics.
    Hot hollow cathode diffuse arc deposition of chromium nitride films2005In: Journal of Vacuum Science and Technology A, ISSN 0734-2101, Vol. 23, no 4, p. 959-963Article in journal (Refereed)
  • 31.
    Bejhed, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rangsten, Pelle
    Köhler, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Demonstration of a single use microsystem valve for high gas pressure applications2007In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 17, no 3, p. 472-481Article in journal (Refereed)
    Abstract [en]

    Demonstrated and characterized here is a single use valve developed for high-pressure applications. Incorporated within the single use valve is a particle filter. The filter serves to remove any particle debris created by the activation process. The valve is solder sealed to be leakage proof. The solder is remelted to obtain activation of the valve. Local heater elements are incorporated on the valve surface together with solder wetting pads. The gas mass flow through the device was evaluated prior to sealing and after activation. The valve was functional at pressures of 100 bar, and opened in less than 10 s with an applied power of 13 W.

  • 32. Bengtsson, Lars
    et al.
    Garcia, Mikael
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    An On-Wafer De-Embedding Technique for Silicon Transistors at Microwave Frequencies1999In: IEEE ICMTS, Gothenburg, Sweden, 1999Conference paper (Other academic)
  • 33.
    Bengtsson, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Design and Characterization of RF-Power LDMOS Transistors2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In mobile communication new applications like wireless internet and mobile video have increased the demand of data-rates. Therefore, new more wideband systems are being implemented. Power amplifiers in the base-stations that simultaneously handle these wideband signals for many terminals (handhelds) need to be highly linear with a considerable band-width.

    In the past decade LDMOS has been the dominating technology for use in these RF-power amplifiers. In this work LDMOS transistors possible to fabricate in a normal CMOS process have been optimized and analyzed for RF-power applications. Their non-linear behavior has been explored using load-pull measurements. The mechanisms of the non-linear input capacitance have been analyzed using 2D TCAD simulations. The investigation shows that the input capacitance is a large contributor to phase distortion in the transistor.

    Computational load-pull TCAD methods have been developed for analysis of RF-power devices in high-efficiency operation. Methods have been developed for class-F with harmonic loading and for bias-modulation. Load-pull measurements with drain-bias modulation in a novel measurement setup have also been conducted. The investigation shows that the combination of computational load-pull of physical transistor structures and direct measurement evaluation with modified load-pull is a viable alternative for future design of RF-power devices. Simulations and measurements on the designed LDMOS shows a 10 to 15 % increase in drain efficiency in mid-power range both in simulations and measurements. The computational load-pull method has also been used to investigate the power capability of LDMOS transistors on SOI. This study indicates that either a low-resistivity or high-resistivity substrate should be used in manufacturing of RF-power LDMOS transistors on SOI to achieve optimum efficiency. Based on a proper substrate selection these devices exhibit a 10 % higher drain-efficiency mainly due to lower dissipated power in the devices.

    List of papers
    1. Novel BiCMOS Compatible, Short Channel LDMOS Technology for Medium Voltage RF & Power Applications
    Open this publication in new window or tab >>Novel BiCMOS Compatible, Short Channel LDMOS Technology for Medium Voltage RF & Power Applications
    2002 (English)In: IEEE MTT-S Digest, 2002, p. 35-39Conference paper, Oral presentation with published abstract (Refereed)
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-97480 (URN)10.1109/MWSYM.2002.1011552 (DOI)
    Conference
    IEEE MTT-S Int Microwave Symposium also in IEEE RFIC Symposium pp 289-292
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2013-11-21
    2. Small Signal and Power Evaluation of Novel BiCMOS -Compatible Short-Channel LDMOS Technology
    Open this publication in new window or tab >>Small Signal and Power Evaluation of Novel BiCMOS -Compatible Short-Channel LDMOS Technology
    2003 (English)In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 51, no 3, p. 1052-1056Article in journal (Refereed) Published
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Research subject
    Electronics
    Identifiers
    urn:nbn:se:uu:diva-97481 (URN)
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2017-12-14
    3. Investigation of the non-linear input capacitance in LDMOS transistors and its contribution to IMD and phase distortion
    Open this publication in new window or tab >>Investigation of the non-linear input capacitance in LDMOS transistors and its contribution to IMD and phase distortion
    2008 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 52, no 7, p. 1024-1031Article in journal (Refereed) Published
    Abstract [en]

    In this paper the mechanisms causing the capacitive, reactive non-linearities in a lateral double diffused MOS, LDMOS, transistor are investigated. The non-linear input capacitance under load-line power match is extracted and analyzed. Computational TCAD load-pull is used to analyze the effect of non-linear capacitance on two-tone intermodulation distortion and AM–PM conversion in class-A operation. High-frequency measurements have been made to verify the use of 2D numerical device simulations for the analysis. It is found that the input capacitance, Cgg, of the LDMOS transistor working under power match conditions is a strongly non-linear function of gate voltage Vg but with an almost linear initial increase in Cgg. The voltage dependence of Cgg is found to mainly affect higher order IMD products in class-A operation. Transient simulations however show that Cgg seriously contributes to the onset of AM–PM conversion well below the 1 dB compression point.

    Keywords
    LDMOS transistors, RF-power, Power amplifiers, IMD, AM–PM conversion
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-97482 (URN)10.1016/j.sse.2008.03.001 (DOI)000257972500006 ()
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2017-12-14
    4. A Method for Device Intermodulation Analysis from 2D, TCAD Simulations using a Time-domain Waveform Approach
    Open this publication in new window or tab >>A Method for Device Intermodulation Analysis from 2D, TCAD Simulations using a Time-domain Waveform Approach
    2006 (English)In: Proceedings of the 36th European Microwave Conference, 2006, p. 169-171Conference paper, Published paper (Refereed)
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-97483 (URN)10.1109/EUMC.2006.281245 (DOI)2-9600551-6-0 (ISBN)
    Conference
    36th European Microwave Conference
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2010-02-18Bibliographically approved
    5. A Computational Load-Pull Method for TCAD Optimization of RF-Power Transistors in Bias-Modulation Applications
    Open this publication in new window or tab >>A Computational Load-Pull Method for TCAD Optimization of RF-Power Transistors in Bias-Modulation Applications
    2008 (English)In: Proceedings of the 3rd European Microwave Integrated Circuits Conference, 2008Conference paper, Published paper (Refereed)
    Abstract [en]

    In this paper a method for TCAD evaluation of RF-Power transistors for high-efficiency operation using drain bias-modulation is presented. The method is based on large signal time-domain transient computational load-pull. With the method, intrinsic device parasitics and mechanisms affecting device efficiency under drain bias modulation can be investigated and optimized for the application making it very useful for RFIC design. A case study has been done on a CMOS compatible LDMOS. For verification under dynamic operation two-tone signals with varying envelope has been simulated. The results show a possible 15% increase in the efficiency of a modulated signal for the studied device at the expense of increased phase distortion observable also in the time-domain waveforms generated. Since the method is based on TCAD it is also useful in the investigation of e.g. dynamic breakdown during high envelope under bias-modulation operation.

    Keywords
    MOS integrated circuits, power transistors, radiofrequency integrated circuits, technology CAD (electronics), CMOS compatible LDMOS, RF-power transistors, RFIC design, TCAD optimization, bias-modulation applications, computational load-pull method
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-97484 (URN)10.1109/EMICC.2008.4772269 (DOI)978-2-87487-007-1 (ISBN)
    Conference
    EuMIC 27-28 Oct. 2008
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2016-04-12
    6. A Computational Load-Pull Method with Harmonic Loading for High-Efficiency Investigations
    Open this publication in new window or tab >>A Computational Load-Pull Method with Harmonic Loading for High-Efficiency Investigations
    2009 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 53, no 1, p. 86-94Article in journal (Refereed) Published
    Abstract [en]

    In this paper a method for TCAD evaluation of RF-power transistors in high-efficiency operation using harmonic loading is presented. The method is based on large signal time-domain computational load-pull. Active loads are used in the harmonic load-pull for simulation time reduction. With the method device performance under different harmonic load impedance can be investigated at an early stage in the design process. Alternative designs can be compared and the mechanisms affecting device efficiency in class-F can be studied at chip-level. For method validation, a case study is made on an LDMOS transistor. The transistor is load-pulled in class-AB and then optimized for efficiency at 2f0 and 3f0 using a novel approach with passive fundamental load and active harmonic loads. A swept simulation is conducted using passive fundamental and harmonic loads. Waveforms in compression are analyzed and the mechanisms creating the increased efficiency in class-F are identified by a comparative study to class-AB. Class-F harmonic termination is shown to give a 17% overall reduction of dissipated power and a 9% increase in output power. The expected efficiency increase is about 3–10% in the compression region depending on level of compression.

    Keywords
    Load-pull, RF-power, Power amplifiers, TCAD
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-97485 (URN)10.1016/j.sse.2008.10.005 (DOI)000262552200015 ()
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2017-12-14
    7. Investigation of SOI-LDMOS for RF-power applications using Computational Load-Pull
    Open this publication in new window or tab >>Investigation of SOI-LDMOS for RF-power applications using Computational Load-Pull
    2009 (English)In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, Vol. 56, no 3, p. 505-511Article in journal (Refereed) Published
    Abstract [en]

    Small-signal and computational load-pull simulations are used to investigate the effect of substrate resistivity on efficiency in high-power operation of high-frequency silicon-on-insulator-LDMOS transistors. Identical transistors are studied on substrates with different resistivities. Using computational load pull, their high-power performance is evaluated. The results are compared to previous investigations, relating the OFF-state output resistance to high-efficiency operation. From the large-signal simulation, an output circuit model based on a load-line match is extracted with parameters traceable from small-signal simulations. It is shown that, albeit high OFF-state output resistance is a good indication, it is not sufficient for high efficiency in a high-power operation. The bias and frequency dependence of the coupling through the substrate makes a more detailed ON-state analysis necessary. It is shown that very low resistivity and high-resistivity SOI substrates both result in a high efficiency at the studied frequency and bias point. It is also shown that a normally doped medium-resistivity substrate results in a significantly lower efficiency.

    Keywords
    LDMOS, RF power, silicon-on-insulator (SOI), technology CAD (TCAD)
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-97486 (URN)10.1109/TED.2008.2011848 (DOI)000264019300019 ()
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2017-12-14
    8. A Novel Load-Pull Configuration for Envelope Tracking Applications
    Open this publication in new window or tab >>A Novel Load-Pull Configuration for Envelope Tracking Applications
    (English)In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670Article in journal (Refereed) Submitted
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-97487 (URN)
    Available from: 2008-09-04 Created: 2008-09-04 Last updated: 2017-12-14
    Download full text (pdf)
    FULLTEXT01
    Download (pdf)
    ERRATA01
  • 34.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Method for Device Intermodulation Analysis from 2D, TCAD Simulations using a Time-domain Waveform Approach2006In: Proceedings of the 36th European Microwave Conference, 2006, p. 169-171Conference paper (Refereed)
  • 35.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A computational load-Pull Investigation of Harmonic Loading effects on AM-PM conversion2008In: Proc of GHz symposium, 2008, p. 83-Conference paper (Refereed)
  • 36.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Computational Load-Pull Method for TCAD Optimization of RF-Power Transistors in Bias-Modulation Applications2008In: Proceedings of the 3rd European Microwave Integrated Circuits Conference, 2008Conference paper (Refereed)
    Abstract [en]

    In this paper a method for TCAD evaluation of RF-Power transistors for high-efficiency operation using drain bias-modulation is presented. The method is based on large signal time-domain transient computational load-pull. With the method, intrinsic device parasitics and mechanisms affecting device efficiency under drain bias modulation can be investigated and optimized for the application making it very useful for RFIC design. A case study has been done on a CMOS compatible LDMOS. For verification under dynamic operation two-tone signals with varying envelope has been simulated. The results show a possible 15% increase in the efficiency of a modulated signal for the studied device at the expense of increased phase distortion observable also in the time-domain waveforms generated. Since the method is based on TCAD it is also useful in the investigation of e.g. dynamic breakdown during high envelope under bias-modulation operation.

  • 37.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Computational Load-Pull Method with Harmonic Loading for High-Efficiency Investigations2009In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 53, no 1, p. 86-94Article in journal (Refereed)
    Abstract [en]

    In this paper a method for TCAD evaluation of RF-power transistors in high-efficiency operation using harmonic loading is presented. The method is based on large signal time-domain computational load-pull. Active loads are used in the harmonic load-pull for simulation time reduction. With the method device performance under different harmonic load impedance can be investigated at an early stage in the design process. Alternative designs can be compared and the mechanisms affecting device efficiency in class-F can be studied at chip-level. For method validation, a case study is made on an LDMOS transistor. The transistor is load-pulled in class-AB and then optimized for efficiency at 2f0 and 3f0 using a novel approach with passive fundamental load and active harmonic loads. A swept simulation is conducted using passive fundamental and harmonic loads. Waveforms in compression are analyzed and the mechanisms creating the increased efficiency in class-F are identified by a comparative study to class-AB. Class-F harmonic termination is shown to give a 17% overall reduction of dissipated power and a 9% increase in output power. The expected efficiency increase is about 3–10% in the compression region depending on level of compression.

  • 38.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Load-Pull Based Device Evaluation Method for Bias Modulated Applications2009In: Proc EuMC 2009, 2009, p. 1461-1464Conference paper (Refereed)
  • 39.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Novel Load-Pull Configuration for Envelope Tracking ApplicationsIn: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670Article in journal (Refereed)
  • 40.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    A Novel Load-Pull Setup with Envelope Calibration for Bias Modulated Measurements2009In: Proc EuMC 2009, 2009, p. 942-945Conference paper (Refereed)
  • 41.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Investigation of SOI-LDMOS for RF-power applications using Computational Load-Pull2009In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, Vol. 56, no 3, p. 505-511Article in journal (Refereed)
    Abstract [en]

    Small-signal and computational load-pull simulations are used to investigate the effect of substrate resistivity on efficiency in high-power operation of high-frequency silicon-on-insulator-LDMOS transistors. Identical transistors are studied on substrates with different resistivities. Using computational load pull, their high-power performance is evaluated. The results are compared to previous investigations, relating the OFF-state output resistance to high-efficiency operation. From the large-signal simulation, an output circuit model based on a load-line match is extracted with parameters traceable from small-signal simulations. It is shown that, albeit high OFF-state output resistance is a good indication, it is not sufficient for high efficiency in a high-power operation. The bias and frequency dependence of the coupling through the substrate makes a more detailed ON-state analysis necessary. It is shown that very low resistivity and high-resistivity SOI substrates both result in a high efficiency at the studied frequency and bias point. It is also shown that a normally doped medium-resistivity substrate results in a significantly lower efficiency.

  • 42.
    Bengtsson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Investigation of the non-linear input capacitance in LDMOS transistors and its contribution to IMD and phase distortion2008In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 52, no 7, p. 1024-1031Article in journal (Refereed)
    Abstract [en]

    In this paper the mechanisms causing the capacitive, reactive non-linearities in a lateral double diffused MOS, LDMOS, transistor are investigated. The non-linear input capacitance under load-line power match is extracted and analyzed. Computational TCAD load-pull is used to analyze the effect of non-linear capacitance on two-tone intermodulation distortion and AM–PM conversion in class-A operation. High-frequency measurements have been made to verify the use of 2D numerical device simulations for the analysis. It is found that the input capacitance, Cgg, of the LDMOS transistor working under power match conditions is a strongly non-linear function of gate voltage Vg but with an almost linear initial increase in Cgg. The voltage dependence of Cgg is found to mainly affect higher order IMD products in class-A operation. Transient simulations however show that Cgg seriously contributes to the onset of AM–PM conversion well below the 1 dB compression point.

  • 43.
    Berg, Sören
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Nyberg, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Kubart, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Sputtering yield amplification in reactive sputtering2010Conference paper (Refereed)
  • 44.
    Bjurström, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Advanced Thin Film Electroacoustic Devices2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The explosive development of the telecom industry and in particular wireless and mobile communications in recent years has lead to a rapid development of new component and fabrication technologies to continually satisfy the mutually exclusive requirements for better performance and miniaturization on the one hand and low cost on the other. A fundamental element in radio communications is time and frequency control, which in turn is achieved by high performance electro-acoustic components made on piezoelectric single crystalline substrates. The latter, however, reach their practical limits in terms of performance and cost as the frequency of operation reaches the microwave range. Thus, the thin film electro-acoustic technology, which uses thin piezoelectric films instead, has been recently developed to alleviate these deficiencies.

    This thesis explores and addresses a number of issues related to thin film synthesis on the one hand as well as component design and fabrication on other. Specifically, the growth of highly c-axis textured AlN thin films has been studied and optimized for achieving high device performance. Perhaps, one of the biggest achievements of the work is the development of a unique process for the deposition of AlN films with a mean c-axis tilt, which is of vital importance for the fabrication of resonators operating in contact with liquids, i.e. biochemical sensors. This opens the way for the development of a whole range of sensors and bio-analytical tools. Further, high frequency Lamb wave resonators have been designed, fabricated and evaluated. Performance enhancement of FBAR devices is also addressed, e.g. spurious mode suppression, temperature compensation, etc. It has been demonstrated, that even without temperature compensation, shear mode resonators operating in a liquid still exhibit an excellent performance in terms of Q (200) and coupling (~1.8%) at 1.2 GHz, resulting in a mass resolution better than 2 ng cm-2 in water, which excels that of today’s quartz sensors.

    List of papers
    1. An accurate direct extraction technique for the MBVD resonator model
    Open this publication in new window or tab >>An accurate direct extraction technique for the MBVD resonator model
    2004 (English)In: Proceedings of 34th European Microwave Conference, 2004, p. 1241-1244Conference paper, Published paper (Refereed)
    National Category
    Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:uu:diva-95545 (URN)1580539920 (ISBN)
    Conference
    European Microwave Conference
    Available from: 2007-03-08 Created: 2007-03-08 Last updated: 2013-11-21
    2. Suppression of spurious lateral modes in thickness-excited FBAR resonators
    Open this publication in new window or tab >>Suppression of spurious lateral modes in thickness-excited FBAR resonators
    2005 (English)In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 52, no 7, p. 1189-1192Article in journal (Refereed) Published
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-93978 (URN)10.1109/TUFFC.2005.1504006 (DOI)
    Available from: 2006-01-27 Created: 2006-01-27 Last updated: 2017-12-14Bibliographically approved
    3. Synthesis of c-axis-oriented AlN thin films on high-conducting layers: Al, Mo, Ti, TiN, and Ni
    Open this publication in new window or tab >>Synthesis of c-axis-oriented AlN thin films on high-conducting layers: Al, Mo, Ti, TiN, and Ni
    Show others...
    2005 (English)In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 52, no 7, p. 1170-1174Article in journal (Refereed) Published
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-95547 (URN)10.1109/TUFFC.2005.1504003 (DOI)16212256 (PubMedID)
    Available from: 2007-03-08 Created: 2007-03-08 Last updated: 2017-12-14Bibliographically approved
    4. Dependence of the electromechanical coupling on the degree of orientation of c-textured thin AlN films
    Open this publication in new window or tab >>Dependence of the electromechanical coupling on the degree of orientation of c-textured thin AlN films
    Show others...
    2004 (English)In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 51, no 10, p. 1347-1353Article in journal (Refereed) Published
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-93979 (URN)10.1109/TUFFC.2004.1350963 (DOI)
    Available from: 2006-01-27 Created: 2006-01-27 Last updated: 2017-12-14Bibliographically approved
    5. Synthesis of textured thin piezoelectric AlN films with a nonzero C-axis mean tilt for the fabrication of shear mode resonators
    Open this publication in new window or tab >>Synthesis of textured thin piezoelectric AlN films with a nonzero C-axis mean tilt for the fabrication of shear mode resonators
    2006 (English)In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 53, no 11, p. 2095-2100Article in journal (Refereed) Published
    Abstract [en]

    A method for the deposition of thin piezoelectric aluminum nitride (AlN) films with a nonzero c-axis mean tilt has been developed. The deposition is done in a standard reactive magnetron sputter deposition system without any hardware modifications. In essence, the method consists of a two-stage deposition process. The resulting film has a distinct tilted texture with the mean tilt of the c-axis varying roughly in the interval 28 to 32 degrees over the radius of the wafer excluding a small exclusion zone at the center of the latter. The mean tilt angle distribution over the wafer has a circular symmetry. A membrane-type shear mode thickness-excited thin film bulk acoustic resonator together with a micro-fluidic transport system has been subsequently fabricated using the two stage AIN deposition as well as standard bulk micro machining of Si. The resonator consisted of a 2-mu m-thick AlN film with 200-nm-thick A1 top and bottom electrodes. The resonator was characterized with a network analyzer when operating in both air and water. The shear mode resonance frequency was about 1.6 GHz, the extracted device Q around 350, and the electromechanical coupling k(t)(2) 2% when the resonator was operated in air, whereas the latter two dropped down to 150 and 1.8%, respectively, when the resonator was operated in pure water.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-23532 (URN)10.1109/TUFFC.2006.149 (DOI)000241566400014 ()
    Available from: 2007-01-30 Created: 2007-01-30 Last updated: 2017-12-07Bibliographically approved
    6. Lateral-field-excited thin-film Lamb wave resonator
    Open this publication in new window or tab >>Lateral-field-excited thin-film Lamb wave resonator
    2005 (English)In: Applied Physics Letters, ISSN 0003-6951, Vol. 86, no 15, p. 154103-Article in journal (Refereed) Published
    Abstract [en]

    The basic principles and technology for the development of lateral-field-excited Lamb acoustic wave resonators on sputter-deposited c-oriented thin aluminum nitride films are presented. The experimental results demonstrate that Lamb waves can be successfully used as an alternative to high-velocity surface acoustic waves.

    Place, publisher, year, edition, pages
    AIP, 2005
    Keywords
    Thin Films, Lamb waves, Resonators, High Frequency, Ultrasonics
    Identifiers
    urn:nbn:se:uu:diva-95550 (URN)10.1063/1.1900312 (DOI)
    Projects
    SSF ICTEA
    Available from: 2007-03-08 Created: 2007-03-08 Last updated: 2010-02-17Bibliographically approved
    7. Thin film Lamb wave resonant structures - The first approach
    Open this publication in new window or tab >>Thin film Lamb wave resonant structures - The first approach
    2006 (English)In: Solid-State Electronics, ISSN 0038-1101, Vol. 50, no 3, p. 322-326Article in journal (Refereed) Published
    Abstract [en]

    Resonant Lamb wave based geometries on c-oriented aluminum nitride (AlN) thin film membranes are studied. Attention has been focused on the lowest order symmetric Lamb mode because of its extremely high velocity approaching 10,600 m/s. The Lamb waves have been excited by means of both inter-digital transducers (IDT) and longitudinal wave (LW) transducers. Two basic reflector geometries have been used along with the conventional one-port resonator topology. The experimental results obtained demonstrate that Lamb waves can be successfully used as an alternative to high velocity surface acoustic waves. A discussion regarding the ways for improving the device performance is provided, and hence future research aspects in the area are identified.

    Keywords
    Ultrasonics, Lamb waves, resonator, Thin film, High frequency
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-95551 (URN)10.1016/j.sse.2006.01.012 (DOI)
    Available from: 2007-03-08 Created: 2007-03-08 Last updated: 2016-06-22Bibliographically approved
    8. Shear mode AlN thin film electro-acoustic resonant sensor operation in viscous media
    Open this publication in new window or tab >>Shear mode AlN thin film electro-acoustic resonant sensor operation in viscous media
    Show others...
    2007 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 123, no 1, p. 466-473Article in journal (Refereed) Published
    Abstract [en]

    A shear mode thin film bulk acoustic resonator (FBAR) operating in liquid media together with a microfluidic transport system is presented. The resonator has been fabricated utilizing a recently developed reactive sputter-deposition process for AlN thin films with inclined c-axis relative to the surface normal with a mean tilt of around 30°. The resonator has a resonance frequency of around 1.2 GHz and a Q value in water of around 150. Sensor operation in water and glycerol solutions is characterized. Theoretical analysis of the sensor operation under viscous load as well as of the sensitivity and stability in general is presented. The theoretical predictions are compared with experimental measurements. The results demonstrate clearly the potential of FBAR biosensors for the fabrication of highly sensitive low cost biosensors, bioanalytical tools as well as for liquid sensing in general.

    Keywords
    AlN, Biosensor, FBAR, Quasi-shear polarized acoustic wave, Thickness mode resonator, Tilted films
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-10554 (URN)10.1016/j.snb.2006.09.028 (DOI)000246171200068 ()
    Projects
    WISENET
    Available from: 2007-04-04 Created: 2007-04-04 Last updated: 2017-12-11Bibliographically approved
    9. Temperature compensation of liquid FBAR sensors
    Open this publication in new window or tab >>Temperature compensation of liquid FBAR sensors
    2007 (English)In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 17, no 3, p. 651-658Article in journal (Refereed) Published
    Abstract [en]

    In this work we demonstrate a practically complete temperature compensation of the second harmonic shear mode in a composite Al/AlN/Al/SiO2 thin film bulk acoustic resonator (FBAR) in the temperature range 25 °C–95 °C. The main advantages of this mode are its higher Q value in liquids as well as its higher frequency and hence higher resolution for sensor applications. For comparative reasons the non-compensated fundamental shear mode is also included in these studies. Both modes have been characterized when operated both in air and in pure water. Properties such as Q value, electromechanical coupling, dissipation and sensitivity are studied. An almost complete temperature compensation of the second harmonic shear mode was observed for an oxide thickness of 1.22 µm for an FBAR consisting of 2 µm thick AlN and 200 nm thick Al electrodes. Thus, the measured temperature coefficient of frequency (TCF) in air for the non-compensated fundamental shear mode (1.25 GHz) varied between −31 and −36 ppm °C−1 over the above temperature range while that of the compensated second harmonic shear mode (1.32 GHz) varied between +2 ppm °C−1 and −2 ppm °C−1 over the same temperature interval. When operated in pure water the former type shows a Q value and coupling coefficient, k2t, around 180 and 2%, respectively, whereas for the second harmonic these are 230 and 1.4%, respectively.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-10269 (URN)10.1088/0960-1317/17/3/030 (DOI)000245433800030 ()
    Projects
    WISENET
    Available from: 2007-03-09 Created: 2007-03-09 Last updated: 2017-12-11Bibliographically approved
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  • 45.
    Bjurström, Johan
    et al.
    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.
    Yantchev, Ventsislav
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lateral-field-excited thin-film Lamb wave resonator2005In: Applied Physics Letters, ISSN 0003-6951, Vol. 86, no 15, p. 154103-Article in journal (Refereed)
    Abstract [en]

    The basic principles and technology for the development of lateral-field-excited Lamb acoustic wave resonators on sputter-deposited c-oriented thin aluminum nitride films are presented. The experimental results demonstrate that Lamb waves can be successfully used as an alternative to high-velocity surface acoustic waves.

  • 46.
    Bjurström, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lidbaum, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electronics. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Experimental Physics.
    Wingqvist, Gunilla
    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.
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Synthesis of highly textured thin piezoelectric AlN films with a tilted c-axis2007Conference paper (Refereed)
  • 47.
    Bjurström, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rosén, Daniel
    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.
    Yantchev, Ventsislav
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Dependence of the Electromechanical Coupling on the Degree of Orientation of c-Textured Thin AlN Films2003In: IEEE Ultrasonics Symposium, Honolulu, Hawaii, USA, 2003, 2003Conference paper (Refereed)
  • 48.
    Bjurström, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rosén, Daniel
    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.
    Yantchev, Ventsislav
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Petrov, Ivan
    Dependence of the electromechanical coupling on the degree of orientation of c-textured thin AlN films2004In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 51, no 10, p. 1347-1353Article in journal (Refereed)
  • 49.
    Bjurström, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Vestling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Olsson, Jörgen
    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.
    An accurate direct extraction technique for the MBVD resonator model2004In: Proceedings of 34th European Microwave Conference, 2004, p. 1241-1244Conference paper (Refereed)
  • 50.
    Bjurström, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Wingqvist, Gunilla
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electronics.
    Katardjiev, Ilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electronics.
    Synthesis of textured thin piezoelectric AlN films with a nonzero c-axis mean tilt for the fabrication of shear mode resonators2005In: Proc Int IEEE Ultrason Symp, 2005Conference paper (Other academic)
1234567 1 - 50 of 345
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