Design and construction of GaAs-based micromachined thermal converter device consisting of a high electron mobility transistor (as a microwave heater) and a thin film resistor (as a temperature sensor), integrated on 1μm thick polyimide fixed GaAs/AlGaAs island structure are introduced. The influence of thermal residual stresses as well as device temperature variations on membrane-like multilayer structure are discussed. A noninvasive and contactless optical methods such as laser confocal microscopy, laser Doppler vibrometry (LDV) and thin layer interferometry are applied to analyze experimentally the thermo-mechanical properties of the micromachined device. LDV method is used to evaluate the device temperature time constant (τc ∼1.5ms) and nano-deformations induced by the temperature changes at any point of device. A confocal microscope is chosen to analyse the 3D deformation profiles of the device at different temperature-induced stress states. The device deformation changes (∼3μm) induced by power dissipation of 9.5mW (temperature increase of 395K) are found to be negligible with respect to the dimensions of the polyimide fixed island structure (160μm×120μm).The optical characterization methods are proved to be a useful tool in design of new thermally based MEMS devices.

GaAs micromachining technologies were used for fabricating polyimide-fixed thermally insulated GaAs Island structure. This structure, fully compatible with GaAs Heterostructure Field Effect Transistor (HFET) technology, was developed to be used for design of Micromechanical Thermal Converter (MTC) device. To fabricate the Island structure front-side surface micromachining is combined with a back-side bulk GaAs micromachining> There is double-side aligned selective reactive ion etching of GaAs and GaAs heterostructures used for three-dimensional patterning of these Island structures using AlGaAs and polyimide as an etch-stop layers.

International Journal of Computational Engineering ScienceVol. 04, No. 03, pp. 543-546 (2003) MaterialsNo AccessMICROMECHANICAL THERMAL CONVERTER DEVICE BASED ON POLYIMIDE-FIXED ISLAND STRUCTURET. LALINSKÝ, M. KRNÁČ, Š. HAŠČÍK, Ž. MOZOLOVÁ, L. MATAY, I. KOSTIČ, P. HRKÚT, J. JAKOVENKO, and M. HUSÁKT. LALINSKÝ Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovakia Search for more papers by this author , M. KRNÁČ Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovakia Search for more papers by this author , Š. HAŠČÍK Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovakia Search for more papers by this author , Ž. MOZOLOVÁ Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovakia Search for more papers by this author , L. MATAYInstitute of Information of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 37 Bratislava, Slovakia Search for more papers by this author , I. KOSTIČInstitute of Information of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 37 Bratislava, Slovakia Search for more papers by this author , P. HRKÚTInstitute of Information of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 37 Bratislava, Slovakia Search for more papers by this author , J. JAKOVENKOCzech Technical University, Dept. of Microelectronics, Technicka 2, 166 27 Prague 6, Czech Republic Search for more papers by this author , and M. HUSÁKCzech Technical University, Dept. of Microelectronics, Technicka 2, 166 27 Prague 6, Czech Republic Search for more papers by this author https://doi.org/10.1142/S146587630300171XCited by:1 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail AbstractDesign technology and characterization of new GaAs island based Micromechanical Thermal Converter (MTC) device are presented. The MTC device introduced consists of pHEMT as a microwave heater and thin film polySi/Ni resistor as a temperature sensor monolithically integrated on polyimide-fixed 1 μm thick GaAs/AlGaAs island structure. The preliminary experimental results in the device electro-thermal conversion evaluation are demonstrated.Keywords:GaAsMEMSHEMTMicromechanical Thermal Converter References T. Lalinskýet al., Electronics Letters 31, 1914 (1995). Crossref, Google ScholarA. Dehéet al., Electronics Letters 32, 2149 (1996). Crossref, Google ScholarE. Burianet al., Sens. Actuators A 68, 372 (1998). Crossref, Google Scholar Lalinský, T., Haščík, Š., Mozolová, Ž., Burian, E., Tomáška, M., Krnáč, M., Škriniarová, J., Držík, M., Kostič, I., and Matay, L.: Mechanically fixed and thermally isolated micromechanical structures for GaAs heterostructures based MEMS devices. In: 35th International Symposium on Microelectronics IMAPS 2002. Denver, USA, September 4-6, 2002. p. 87 . Google Scholar T. Lalinský, P. Hrkút, Ž. Mozolová, T. Kovačik and A. Krajcer: "Thermal Performance and Stability of Poly Si/Pt(Ni) Thin Film Temperature Sensors on GaAs", Proceedings of the 11th International Conference on Solid-State Sensors and Actuators, June 10-14, Munich, pp. 1496-1499, (2001) . Google Scholar FiguresReferencesRelatedDetailsCited By 1Thermo-mechanical characterization of micromachined GaAs-based thermal converter using contactless optical methodsT. Lalinský, M. Držík, J. Chlpík, M. Krnáč and Š. Haščík et al.1 Sep 2005 | Sensors and Actuators A: Physical, Vol. 123-124 Recommended Vol. 04, No. 03 Metrics History Keywords GaAs MEMSHEMTMicromechanical Thermal ConverterPDF download

A new micromachining technology of mechanically fixed and thermally insulated cantilevers, bridges and islands was developed to be used for design of GaAs heterostructure based microelectromechanical systems (MEMS) devices. Based on the micromachining technology, two different MEMS devices were designed and analyzed. The first one was micromechanical thermal converter (MTC) and the second one was a micromechanical coplanar waveguide (MCPW). The basic electro‐thermal as well as microwave properties of the MEMS devices designed are investigated. The results obtained are also supported by simulation. The advantages of the fixed micromechanical structures in the field of design of new MEMS devices are discussed.

GaAs/AlGaAs and InGaP membrane bridges micromachined on GaAs substrates have been developed for use as supporting micromechanical structures for coplanar waveguides. The internal mechanical stresses potentially induced in these micromechanical devices are evaluated analytically, and also by both the acoustic pressure bulging method and free cantilever deformation measurement. The microwave transmission properties of the micromechanical coplanar waveguides are investigated. The amplitude attenuation at a frequency of 20 GHz is found to be 1.3 dB mm−1 for GaAs/AlGaAs bridge-based devices of a length of 900 μm and a slot of 3 μm. We discuss the potential applications of the fabricated micromechanical devices.

R,F power transistor design in standard CMOS technology for the power amplifier in the frequency region of 1800MH: is key issue ill this work. Transistor application in standard RF power amplifier topology is discussed in the sense of output power as well as power added efficiency, The RF CMOS power transistor layout is designed ill Cadence Virtuoso layout editor using AustriaMicroSystems 0.35mu CMOS technology. The RF power achieved at 50 Ohm load using designed transistor in class E power amplifier was 1 W at 1750 MHz with power added efficiency of 59.2% at 2.3 V power supply voltage.

The design, fabrication and characterization of microwave transmission structures on thin composite semiconductor/dielectric substrates, technologically compatible with pseudomorphic HFETs, for micromechanical microwave transmitted power sensors are discussed. The AlGaAs/InGaAs/GaAs and InGaP/InGaAs/GaAs HFET structures as supporting layers of micromachined coplanar waveguides for low loss microwave power transmission are compared.

The design, fabrication and characterization of microwave transmission structure on thin composite semiconductor/dielectric substrate technologically compatible with pseudomorphic HFETs for a micromechanical microwave transmitted power sensor are discussed.

GaAs MSM photodetectors with AlAs/GaAs DBR structures designed for an operating wavelength of 840 nm were characterized in the frequency and time domains. The frequency response of the MSMs, using a lightwave set-up and HP8408 network analyzer, was measured. The photodetector response to the optical pulse of a fast laser diode excitation was evaluated. 3-dB bandwidth in excess of 4 GHz was obtained. Frequency and pulse responses dependence on photodetector bias was characterized.