Zhang Wei,Yao Suying,Zhang Shengcai,Zhao Yiqiang,Zhang Weixin
(School of Electronic Information Engineering,Tianjin University,Tianjin 300072,China)
Abstract:With the help of finite element analysis tool,ANSYS,a highª²temperature piezoresistive pressure sensor based on silicon on insulator was designed. The aspect ratio of the rectangular strain diaphragm was determined to 1:2 to get larger output and smaller chip size. Samples were fabricated and measured compared to polysilicon piezoresistive pressure sensors with the same structure and fabrication process. The results show that the sensitivity of the pressure sensor reaches 220mV/MPa,much higher than that of polysilicon pressure sensor £¨about 50mV/MPa£©. Moreover,it can work at 200¡æ, and has good performance on longª²term stability. The offset drift is 0.12% full scale in 30 days.
Keywords:pressure sensor£»silicon on insulator;high-temperature;finite element analysis