Preliminary evaluation of the influence of the temperature on the performance of a piezoresistive pressure sensor based on a-SiC film (original) (raw)
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Design, analysis and fabrication of 4H–SiC diaphragm for piezoresistive MEMS pressure sensor
ISSS Journal of Micro and Smart Systems, 2021
A diaphragm-based MEMS pressure sensor, suitable for harsh environments, was designed, simulated, analyzed and virtually fabricated on p -type SiC epitaxial semi-insulating 4H–SiC substrate to measure the external pressure in the range of 0–8 MPa using device simulation software. The critical component of the pressure sensor is a thin flat square SiC diaphragm with an area of 1500 µm × 1500 µm and thickness of 75 µm. The area and thickness were optimized by performing computer simulation using the finite element method of simulation. The p -type SiC resistors were virtually fabricated in Wheatstone bridge configuration on top of the SiC diaphragm to convert the mechanical stress signal, generated due to external pressure into an electrical output voltage signal. The 4H–SiC MEMS pressure sensor was virtually fabricated on high-purity semi-insulating SiC substrate by dry etching method and its sensitivity was obtained at 2.42 µV/V/KPa for the operating pressure range. A thin SiC diaph...