The Experts below are selected from a list of 64470 Experts worldwide ranked by ideXlab platform
K Sheng - One of the best experts on this subject based on the ideXlab platform.
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reliability issues of sic mosfets a technology for High Temperature Environments
IEEE Transactions on Device and Materials Reliability, 2010Co-Authors: Greg Dunne, Kevin Matocha, Kin P Cheung, John S Suehle, K ShengAbstract:The wide-bandgap nature of silicon carbide (SiC) makes it an excellent candidate for applications where High Temperature is required. The metal-oxide-semiconductor (MOS)-controlled power devices are the most favorable structure; however, it is widely believed that silicon oxide on SiC is physically limited, particularly at High Temperatures. Therefore, experimental measurements of long-term reliability of oxide at High Temperatures are necessary. In this paper, time-dependent dielectric-breakdown measurements are performed on state-of-the-art 4H-SiC MOS capacitors and double-implanted MOS field-effect transistors (DMOSFET) with stress Temperatures between 225°C and 375°C and stress electric fields between 6 and 10 MV/cm. The field-acceleration factor is around 1.5 dec/(MV/cm) for all of the Temperatures. The thermal activation energy is found to be ~ 0.9 eV, independent of the electric field. The area dependence of Weibull slope is discussed and shown to be a possible indication that the oxide quality has not reached the intrinsic regime and further oxide-reliability improvements are possible. Since our reliability data contradict the widely accepted belief that silicon oxide on SiC is fundamentally limited by its smaller conduction-band offset compared with Si, a detailed discussion is provided to examine the arguments of the early predictions.
Qiulin Tan - One of the best experts on this subject based on the ideXlab platform.
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an insertable passive lc pressure sensor based on an alumina ceramic for in situ pressure sensing in High Temperature Environments
Sensors, 2015Co-Authors: Jijun Xiong, Ping-gang Jia, Xiaoyong Chen, Chen Li, Jun Liu, Chenyang Xue, Wendong Zhang, Qiulin TanAbstract:Pressure measurements in High-Temperature applications, including compressors, turbines, and others, have become increasingly critical. This paper proposes an implantable passive LC pressure sensor based on an alumina ceramic material for in situ pressure sensing in High-Temperature Environments. The inductance and capacitance elements of the sensor were designed independently and separated by a thermally insulating material, which is conducive to reducing the influence of the Temperature on the inductance element and improving the quality factor of the sensor. In addition, the sensor was fabricated using thick film integrated technology from High-Temperature materials that ensure stable operation of the sensor in High-Temperature Environments. Experimental results showed that the sensor accurately monitored pressures from 0 bar to 2 bar at Temperatures up to 800 °C. The sensitivity, linearity, repeatability error, and hysteretic error of the sensor were 0.225 MHz/bar, 95.3%, 5.5%, and 6.2%, respectively.
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a High Temperature capacitive pressure sensor based on alumina ceramic for in situ measurement at 600 c
Sensors, 2014Co-Authors: Qiulin Tan, Ping-gang Jia, Zhong Ren, Jijun Xiong, Yingping Hong, Chen Li, Jun Liu, Chenyang Xue, Wendong Zhang, Tao LuoAbstract:In response to the growing demand for in situ measurement of pressure in High-Temperature Environments, a High Temperature capacitive pressure sensor is presented in this paper. A High-Temperature ceramic material-alumina is used for the fabrication of the sensor, and the prototype sensor consists of an inductance, a variable capacitance, and a sealed cavity integrated in the alumina ceramic substrate using a thick-film integrated technology. The experimental results show that the proposed sensor has stability at 850 °C for more than 20 min. The characterization in High-Temperature and pressure Environments successfully demonstrated sensing capabilities for pressure from 1 to 5 bar up to 600 °C, limited by the sensor test setup. At 600 °C, the sensor achieves a linear characteristic response, and the repeatability error, hysteresis error and zero-point drift of the sensor are 8.3%, 5.05% and 1%, respectively.
Greg Dunne - One of the best experts on this subject based on the ideXlab platform.
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reliability issues of sic mosfets a technology for High Temperature Environments
IEEE Transactions on Device and Materials Reliability, 2010Co-Authors: Greg Dunne, Kevin Matocha, Kin P Cheung, John S Suehle, K ShengAbstract:The wide-bandgap nature of silicon carbide (SiC) makes it an excellent candidate for applications where High Temperature is required. The metal-oxide-semiconductor (MOS)-controlled power devices are the most favorable structure; however, it is widely believed that silicon oxide on SiC is physically limited, particularly at High Temperatures. Therefore, experimental measurements of long-term reliability of oxide at High Temperatures are necessary. In this paper, time-dependent dielectric-breakdown measurements are performed on state-of-the-art 4H-SiC MOS capacitors and double-implanted MOS field-effect transistors (DMOSFET) with stress Temperatures between 225°C and 375°C and stress electric fields between 6 and 10 MV/cm. The field-acceleration factor is around 1.5 dec/(MV/cm) for all of the Temperatures. The thermal activation energy is found to be ~ 0.9 eV, independent of the electric field. The area dependence of Weibull slope is discussed and shown to be a possible indication that the oxide quality has not reached the intrinsic regime and further oxide-reliability improvements are possible. Since our reliability data contradict the widely accepted belief that silicon oxide on SiC is fundamentally limited by its smaller conduction-band offset compared with Si, a detailed discussion is provided to examine the arguments of the early predictions.
Kevin P Chen - One of the best experts on this subject based on the ideXlab platform.
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multiplexable intrinsic fabry perot interferometers inscribed by femtosecond laser for vibration measurement in High Temperature Environments
Sensors and Actuators A-physical, 2021Co-Authors: Mohan Wang, Yang Yang, Kevin P ChenAbstract:Abstract This paper reports fabrication technique and demodulation algorithm developments to use multiplexable intrinsic Fabry-Perot interferometer (IFPI) fiber sensor array for distributed vibration measurements at High Temperatures. Using femtosecond laser direct writing scheme, IFPI array were fabricated through laser-induced Type II scattering points in single mode fiber cores. Reflection spectra of IFPI array were demodulated in real-time using modified Bunemen frequency analysis. The demodulation algorithm, which was implemented using a photodetector-array spectrometer, achieves 64-ne dynamic strain resolution at 1-kHz spectral acquisition rate and 2-kHz maximum vibration bandwidth. Performance and stabilities of IFPI sensor array were characterized from room Temperatures to 800 °C. The static strain resolution was 0.6 μe and the minimum detectable dynamic strain amplitude was 23 ne/√Hz at 800 °C. The multiplex performance was also tested by measuring dynamic strain in time domain through six IFPI sensor array fabricated in one fiber. This paper presents an integrated and low-cost sensing solution to perform distributed vibration measurements in harsh Environments.
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sapphire fiber optical hydrogen sensors for High Temperature Environments
IEEE Photonics Technology Letters, 2016Co-Authors: Aidong Yan, Rongzhang Chen, Mohamed S Zaghloul, Zsolt L Poole, Paul R Ohodnicki, Kevin P ChenAbstract:This letter presents a High-Temperature fiber optical hydrogen sensor with operational Temperatures up to 800 °C. The sensor is based on a single-crystal sapphire fiber coated with Pd nanoparticles incorporated TiO2 nanostructured thin film. The template-based sol-gel chemistry was applied to synthesize the nanostructured porous thin films. The sensitivity and response time of the sensor was evaluated for hydrogen concentrations varying from 0.02% to 4%. The effects of Temperature on the hydrogen gas sensing properties were investigated from 600 °C to 800 °C.
Jijun Xiong - One of the best experts on this subject based on the ideXlab platform.
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an insertable passive lc pressure sensor based on an alumina ceramic for in situ pressure sensing in High Temperature Environments
Sensors, 2015Co-Authors: Jijun Xiong, Ping-gang Jia, Xiaoyong Chen, Chen Li, Jun Liu, Chenyang Xue, Wendong Zhang, Qiulin TanAbstract:Pressure measurements in High-Temperature applications, including compressors, turbines, and others, have become increasingly critical. This paper proposes an implantable passive LC pressure sensor based on an alumina ceramic material for in situ pressure sensing in High-Temperature Environments. The inductance and capacitance elements of the sensor were designed independently and separated by a thermally insulating material, which is conducive to reducing the influence of the Temperature on the inductance element and improving the quality factor of the sensor. In addition, the sensor was fabricated using thick film integrated technology from High-Temperature materials that ensure stable operation of the sensor in High-Temperature Environments. Experimental results showed that the sensor accurately monitored pressures from 0 bar to 2 bar at Temperatures up to 800 °C. The sensitivity, linearity, repeatability error, and hysteretic error of the sensor were 0.225 MHz/bar, 95.3%, 5.5%, and 6.2%, respectively.
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a High Temperature capacitive pressure sensor based on alumina ceramic for in situ measurement at 600 c
Sensors, 2014Co-Authors: Qiulin Tan, Ping-gang Jia, Zhong Ren, Jijun Xiong, Yingping Hong, Chen Li, Jun Liu, Chenyang Xue, Wendong Zhang, Tao LuoAbstract:In response to the growing demand for in situ measurement of pressure in High-Temperature Environments, a High Temperature capacitive pressure sensor is presented in this paper. A High-Temperature ceramic material-alumina is used for the fabrication of the sensor, and the prototype sensor consists of an inductance, a variable capacitance, and a sealed cavity integrated in the alumina ceramic substrate using a thick-film integrated technology. The experimental results show that the proposed sensor has stability at 850 °C for more than 20 min. The characterization in High-Temperature and pressure Environments successfully demonstrated sensing capabilities for pressure from 1 to 5 bar up to 600 °C, limited by the sensor test setup. At 600 °C, the sensor achieves a linear characteristic response, and the repeatability error, hysteresis error and zero-point drift of the sensor are 8.3%, 5.05% and 1%, respectively.