A batch-microfabricated 6H-SiC diaphragm-based piezoresistive pressure sensors with working temperature range between 80°F to 500°F had been produced. The net output voltage shows an output voltage of 131.59 mV at full-scale pressure of 1000 psi. The net output voltage response to temperature up to 500°F is also presented. The Temperature Coefficient of Resistance (TCR) of the device exhibits a TCR of -3.07%/100°F at 180°F and eventually becomes a positive value of 4.24%/100°F at 500°F. The Temperature Coefficient of Gage Factor (TCGF) exhibits negative values of -15%/100°F and -10%/100°F at 180°F and 500°F, respectively. The problem of micropipes in 6H-SiC was effectively resolved, making it possible to fabricate thin diaphragms of about 25 μm
Date of Conference: 11-15 Feb 1996