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6 results on '"Omar Elmazria"'

1. Hypersonic characterization of sound propagation velocity in AlxGa1−xN thin films

Author

Omar Elmazria, F. Omnès, Carlos Prieto, E. Rodrı́guez-Cañas, Mercedes Vila, R. J. Jiménez Riobóo, Oliver Ambacher, M. A. Sánchez, Tomas Palacios, Fernando Calle, and Badreddine Assouar

Subjects
Brillouin Spectroscopy, Materials science, business.industry, Wave propagation, Wide-bandgap semiconductor, General Physics and Astronomy, Acoustic wave, Substrate (electronics), Sputter deposition, Condensed Matter::Materials Science, Optics, Group velocity, Thin film, business
Abstract

Sound propagation velocity of surface acoustic waves (SAWs) and bulk acoustic waves (BAWs) has been investigated by means of high resolution Brillouin spectroscopy. The results show a linear dependence of the BAW propagation velocity with the Al concentration. There is no relevant influence of the substrate chosen in the propagation velocity of BAWs in AlxGa1−xN thin films. SAW propagation velocity of epitaxially grown AlN is clearly lower than the observed one in AlN prepared by reactive dc magnetron sputtering. Numerical simulation results of SAW propagation velocity are compared with the experimental results.

Published
2002
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2. High temperature gradient nanogap-Pirani micro-sensor with maximum sensitivity around atmospheric pressure

Author

Eric Garnier, Romain Viard, Alain Merlen, Omar Elmazria, M. Moutaouekkil, Q. Gallas, Philippe Pernod, Abdelkrim Talbi, Cécile Ghouila-Houri, ONERA - The French Aerospace Lab [Palaiseau], ONERA-Université Paris Saclay (COmUE), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire International associé sur les phénomènes Critiques et Supercritiques en électronique fonctionnelle, acoustique et fluidique (LIA LICS/LEMAC), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Acoustique Impulsionnelle & Magnéto-Acoustique Non linéaire - Fluides, Interfaces Liquides & Micro-Systèmes - IEMN (AIMAN-FILMS-IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Fluiditech (Thurmelec), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Lille], ONERA, ONERA - The French Aerospace Lab [Meudon], Institut d’Électronique, de Microélectronique et de Nanotechnologie - Département Opto-Acousto-Électronique - UMR 8520 (IEMN-DOAE), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)-Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), and Acoustique Impulsionnelle & Magnéto-Acoustique Non linéaire - Fluides, Interfaces Liquides & Micro-Systèmes - IEMN (AIMAN-FILMS - IEMN)

Subjects
Physics and Astronomy (miscellaneous), CAPTEUR PIRANI, Analytical chemistry, CAPTEUR PRESSION MEMS, 02 engineering and technology, Pirani sensor, 01 natural sciences, Temperature measurement, law.invention, law, Nanosensor, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Silicon oxide, 010302 applied physics, Atmospheric pressure, business.industry, Chemistry, 021001 nanoscience & nanotechnology, Pressure sensor, MEMS pressure sensors, Flow control, Temperature gradient, Surface micromachining, Pressure measurement, Optoelectronics, 0210 nano-technology, business
Abstract

International audience; This letter describes and discusses the design and testing of an effcient nanogap Pirani micro-sensor for pressure measurements in a wide range with a maximum sensitivity around atmospheric pressure. The structure combines a substrate-free heated wire and mechanical support using silicon oxide micro-bridges allowing both a constant nanoscale gap between the wire and the substrate and a 1 mm long and 3 µm wide wire. The high aspect ratio of wire provides a uniform heating profile along the wire and contributes to low pressure detection. At the opposite, both the nanoscale gap and the short wire length between two micro-bridges contributes to shift the high pressure limit. Tested between 10 kPa and 800 kPa, the sensor presents a wide measurement range, not fully reached by the experiments, with a maximum of sensitivity close to the atmospheric pressure and performances with up to 38 %/dec sensitivity when operation in constant temperature mode with an overheat of 20 °C.

Published
2017
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3. Surface acoustic wave propagation in aluminum nitride-unpolished freestanding diamond structures

Author

M.B. Assouar, Geert Vanhoyland, Vincent Mortet, Marc D'olieslaeger, Omar Elmazria, Milos Nesladek, Patrick Alnot, and Jan D'Haen

Subjects
Electromechanical coupling coefficient, Materials science, Physics and Astronomy (miscellaneous), business.industry, Material properties of diamond, Surface acoustic wave, Nucleation, Diamond, Chemical vapor deposition, engineering.material, Nitride, Optics, engineering, Composite material, Thin film, business
Abstract

High-quality surface acoustic wave (SAW) filters based on aluminum nitride (AlN)/diamond layered structures were prepared using the nucleation side of polycrystalline chemical vapor deposition (CVD) diamond, removed from a silicon substrate by wet etching. Highly oriented AlN thin films with optimized piezoelectric properties and with various thicknesses were sputtered onto the nucleation side of freestanding diamond. The effect of AlN thickness on the SAW phase velocity, the coupling coefficient, and the device characteristics were investigated. Experimental results show that the Rayleigh wave and the higher modes are generated. These results agree well with calculated dispersion curves and demonstrate that a high electromechanical coupling coefficient together with a high phase velocity can be obtained by using the nucleation side of freestanding CVD diamond layer.

Published
2002
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4. AlN/ZnO/diamond structure combining isolated and surface acoustic waves

Author

Dmitry Tsimbal, Omar Elmazria, Laurent Le Brizoual, Frederic Sarry, M. A. Djouadi, Sergei Zhgoon, Laboratoire de physique des milieux ionisés et applications (LPMIA), Université Henri Poincaré - Nancy 1 (UHP)-Centre National de la Recherche Scientifique (CNRS), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), and Université de Nantes (UN)-Université de Nantes (UN)

Subjects
010302 applied physics, Frequency response, Materials science, Physics and Astronomy (miscellaneous), business.industry, Wide-bandgap semiconductor, Diamond, 02 engineering and technology, Acoustic wave, engineering.material, 021001 nanoscience & nanotechnology, 01 natural sciences, Finite element method, Resonator, Optics, Excited state, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], engineering, Diamond cubic, 0210 nano-technology, business
Abstract

International audience; In order to generate surface acoustic waves (SAW) and waveguiding layer acoustic waves (WLAW) simultaneously, a multilayer structure of AlN/ZnO/diamond has been proposed. This structure has been investigated theoretically (two-dimensional finite element method) and experimentally. The nature of the excited modes and their order were identified by modeling and confirmed experimentally by measuring the frequency response of the device in the air and in contact with the liquid. The demonstrated structure can be used to realize a packageless sensor or resonator, using the WLAW alone. A temperature compensated gas or liquid sensor can also be realized by combined usage of the SAW and the WLAW.

Published
2009
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5. Innovative surface acoustic wave sensor for accurate measurement of subatmospheric pressure

Author

L. Bouvot, Omar Elmazria, N. Marche, H. Kambara, Pascal Nicolay, and Frederic Sarry

Subjects
Materials science, Physics and Astronomy (miscellaneous), Acoustics, Surface acoustic wave, Measure (physics), Diaphragm (mechanical device), Surface acoustic wave sensor, Pressure sensor, Acoustical measurements and instrumentation
Abstract

An original application for surface acoustic wave (SAW) subatmospheric pressure sensor was developed to measure pressure below 100mTorr with very high precision. The basic operating principles and the most significant experimental results of the sensor are presented here. A simple theoretical model is proposed. This sensor provides an efficient measuring solution in a wide range of subatmospheric pressure, which has been inaccessible in past by conventional diaphragm-based SAW sensors.

Published
2008
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6. 5GHz surface acoustic wave devices based on aluminum nitride/diamond layered structure realized using electron beam lithography

Author

Patrick Alnot, M.B. Assouar, P. Kirsch, Vincent Mortet, and Omar Elmazria

Subjects
Electromechanical coupling coefficient, Materials science, Physics and Astronomy (miscellaneous), business.industry, Surface acoustic wave, Diamond, Chemical vapor deposition, engineering.material, Condensed Matter::Materials Science, symbols.namesake, Dispersion (optics), engineering, symbols, Optoelectronics, Rayleigh wave, business, Lithography, Electron-beam lithography
Abstract

Very high frequency surface acoustic wave (SAW) devices based on AlN/diamond layered structures were fabricated by direct writing using e-beam lithography on the nucleation side of chemical vapor deposition diamond. The interdigital transducers made in aluminum with resolutions down to 500nm were patterned on AlN/diamond layered structure with an adapted technological process. Experimental results show that the Rayleigh wave and the higher modes are generated. The fundamental frequency around 5GHz was obtained for this layered structure SAW device and agrees well with calculated results from dispersion curves of propagation velocity and electromechanical coupling coefficient.

Published
2006
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