The Experts below are selected from a list of 2607 Experts worldwide ranked by ideXlab platform
Zoran Samardžija - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of thick Film Resistor series for strain sensors
Journal of the European ceramic society, 2016Co-Authors: Marko Hrovat, Darko Belavic, Zoran SamardžijaAbstract:Some 10 kohm/sq. thick Film Resistors based on RuO2, ruthenates or a mixture of RuO2 and ruthenates, were evaluated for strain gauge applications. The Resistors were fired at differenttemperatures to estimate the influence of firing temperature on the electrical characteristics. Temperature coefficients of resistivity (TCR), noise indices and gauge factors (GF) were measured. Microstructures of the thick Film Resistors were analysed by SEM. The results indicate that the microstructure of thick Film Resistors influences the gauge factors much more significantly than the "nature" of the conductive phase.
Marko Hrovat - One of the best experts on this subject based on the ideXlab platform.
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Investigation on electrical and microstructural properties of Thick Film Lead-Free Resistor series under various firing conditions
Journal of materials science, Materials in electronics, 2017Co-Authors: Marko Hrovat, Konrad Kiełbasiński, Janez Holc, Darko Belavic, Małgorzata Jakubowska, Anna MłożniakAbstract:The paper presents investigation of four lead free thick Film Resistor pastes, developed at ITME, denoted R-100, R-1k, R-10k and R-100k with sheet resistivities of 0.1, 1, 10 and 100 k?/? were based on RuO 2 as the conductive phase. The aim of the work was to evaluate the influence of firing conditions of the resistive pastes on a sintering process. The pastes were screen printed onto alumina substrate with prefired AgPd lead-free terminations. They were fired at several temperatures from 750 to 950 °C for 10 min at peak temperature, as well as fired at the highest temperature for 6 h, in order to bring the sintering process into the equilibrium. The properties of the Resistors, i.e, sheet resistivity and temperature coefficient of resistance (TCR), microstructure changes, glass crystallization upon firing, etc., were examined. Dried and fired Resistor samples were evaluated by X-Ray diffraction analysis and by the scanning electron microscopy. The RuO 2 conductive phase maintained the same crystal structure regardless of the firing conditions. No devitrification was observed in lead-free Resistors glasses. The lattice constants of RuO 2 were uniform after firing at temperatures over 800 °C. The Resistors matched the desired resistivity and the TCR was the least temperature dependent at the firing temperatures around 850 °C. © 2010 Springer Science+Business Media, LLC.
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Characterisation of thick Film Resistor series for strain sensors
Journal of the European ceramic society, 2016Co-Authors: Marko Hrovat, Darko Belavic, Zoran SamardžijaAbstract:Some 10 kohm/sq. thick Film Resistors based on RuO2, ruthenates or a mixture of RuO2 and ruthenates, were evaluated for strain gauge applications. The Resistors were fired at differenttemperatures to estimate the influence of firing temperature on the electrical characteristics. Temperature coefficients of resistivity (TCR), noise indices and gauge factors (GF) were measured. Microstructures of the thick Film Resistors were analysed by SEM. The results indicate that the microstructure of thick Film Resistors influences the gauge factors much more significantly than the "nature" of the conductive phase.
Wolfgang Nitsche - One of the best experts on this subject based on the ideXlab platform.
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aeromems wall hot wire anemometer on polyimide substrate featuring top side or bottom side bondpads
IEEE Sensors Journal, 2007Co-Authors: U. Buder, Andanton Berns, R. Petz, Wolfgang Nitsche, Ernst ObermeierAbstract:Design, manufacturing, calibration, and basic characterization of a microelectromechanical systems (MEMS) wall hot wire sensor on a flexible polyimide substrate are presented. A configuration exhibiting bond pads on the top side of the foil, as well as an improved setup featuring a through-foil metallization and bottom side bond pads were established. Both sensor designs make use of a highly sensitive nickel thin-Film Resistor spanning a reactive ion etched cavity in a polyimide substrate. The polyimide base material enables the sensor to be adapted to curved aerodynamic surfaces, e.g., airfoils and turbine blades. A mismatch of curvature of aerodynamic surface and silicon sensor surface, as observed with previously presented MEMS hot-wire anemometers is avoided. The combination of polyimide's low thermal conductivity and a cavity featuring FEM-optimized dimensions accounts for a very low-power consumption (<25 mW). Fluctuations in wall shear stress up to 85 kHz can be resolved in constant-temperature mode. An average sensitivity of 0.166 V/(N/m2) is achieved in a wall shear stress range from 0 to 0.72 N/m2. The specifically designed through-foil metallization process allows for electrical contacts to be positioned on the backside of the substrate, thus effectively minimizing aerodynamic disturbances.
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aeromems wall hot wire anemometer on polyimide foil for measurement of high frequency fluctuations
IEEE Sensors, 2005Co-Authors: U. Buder, Andanton Berns, R. Petz, Ernst Obermeier, Wolfgang NitscheAbstract:Design, simulation, manufacturing, calibration, and basic characterization of a MEMS wall hot-wire anemometer is presented. A highly sensitive nickel thin Film Resistor spanning a reactive ion etched cavity in a polyimide foil is employed. This sensor is the first in literature to feature both a thermally insulating cavity and a flexible base material. The polyimide base material allows adopting of the sensor to aerodynamic surfaces, e.g. airfoils and turbine blades. A mismatch of curvature of aerodynamic surface and silicon sensor surface, as observed with previously presented MEMS hot-wire anemometers, is avoided. The combination of polyimide's low thermal conductivity and a cavity featuring FEM-optimized dimensions accounts for a very low power consumption (<30 mW). Fluctuations in wall shear stress up to 80 kHz can be resolved in constant-temperature mode. An average sensitivity of 0.44 V/(N/m2) is achieved in a wall shear stress range from 0 to 0.25 N/m2
Ruxu Du - One of the best experts on this subject based on the ideXlab platform.
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optimization of sputtering parameters for ni cr alloy deposition on copper foil as embedded thin Film Resistor
Surface & Coatings Technology, 2013Co-Authors: Wenjin Zeng, Xianzhu Fu, Ruxu DuAbstract:Abstract Ni–Cr (80/20 at.%) alloy was deposited on the copper foil substrate by DC magnetron sputtering process. Taguchi method was applied to optimize the deposition parameters including sputtering power, substrate temperature, and argon pressure. Sputtering power was found to be the most prominent factor that influenced the electrical properties of Ni–Cr alloy Film by employing the range analysis. Embedded thin Film Resistor (ETFR) with a high resistivity of 6.69 × 10 − 4 Ω.cm and a low temperature coefficient of resistance of 374.78 ppm/K was obtained under the optimized deposition conditions. A feasible way was demonstrated to fabricate high-quality Ni–Cr alloy on copper foil as ETFR materials.
Ernst Obermeier - One of the best experts on this subject based on the ideXlab platform.
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aeromems wall hot wire anemometer on polyimide substrate featuring top side or bottom side bondpads
IEEE Sensors Journal, 2007Co-Authors: U. Buder, Andanton Berns, R. Petz, Wolfgang Nitsche, Ernst ObermeierAbstract:Design, manufacturing, calibration, and basic characterization of a microelectromechanical systems (MEMS) wall hot wire sensor on a flexible polyimide substrate are presented. A configuration exhibiting bond pads on the top side of the foil, as well as an improved setup featuring a through-foil metallization and bottom side bond pads were established. Both sensor designs make use of a highly sensitive nickel thin-Film Resistor spanning a reactive ion etched cavity in a polyimide substrate. The polyimide base material enables the sensor to be adapted to curved aerodynamic surfaces, e.g., airfoils and turbine blades. A mismatch of curvature of aerodynamic surface and silicon sensor surface, as observed with previously presented MEMS hot-wire anemometers is avoided. The combination of polyimide's low thermal conductivity and a cavity featuring FEM-optimized dimensions accounts for a very low-power consumption (<25 mW). Fluctuations in wall shear stress up to 85 kHz can be resolved in constant-temperature mode. An average sensitivity of 0.166 V/(N/m2) is achieved in a wall shear stress range from 0 to 0.72 N/m2. The specifically designed through-foil metallization process allows for electrical contacts to be positioned on the backside of the substrate, thus effectively minimizing aerodynamic disturbances.
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aeromems wall hot wire anemometer on polyimide foil for measurement of high frequency fluctuations
IEEE Sensors, 2005Co-Authors: U. Buder, Andanton Berns, R. Petz, Ernst Obermeier, Wolfgang NitscheAbstract:Design, simulation, manufacturing, calibration, and basic characterization of a MEMS wall hot-wire anemometer is presented. A highly sensitive nickel thin Film Resistor spanning a reactive ion etched cavity in a polyimide foil is employed. This sensor is the first in literature to feature both a thermally insulating cavity and a flexible base material. The polyimide base material allows adopting of the sensor to aerodynamic surfaces, e.g. airfoils and turbine blades. A mismatch of curvature of aerodynamic surface and silicon sensor surface, as observed with previously presented MEMS hot-wire anemometers, is avoided. The combination of polyimide's low thermal conductivity and a cavity featuring FEM-optimized dimensions accounts for a very low power consumption (<30 mW). Fluctuations in wall shear stress up to 80 kHz can be resolved in constant-temperature mode. An average sensitivity of 0.44 V/(N/m2) is achieved in a wall shear stress range from 0 to 0.25 N/m2