Multifunction sensor for pressure and acceleration measurements based on nano-polysilicon thin film resistors

A multifunction sensor based on nano-polysilicon thin film resistors which consists of pressure sensor and acceleration sensor is described. The two Wheatstone bridges consisting of piezoresistors are designed on the surface of square silicon membrane and the root of cantilever beam, respectively. The chips of pressure and acceleration sensors are fabricated on silicon wafer with 〈100〉 orientation by micro-electromechanical system (MEMS) technology and complementary metal oxide semiconductor (CMOS) technology, and they are packaged on a printed circuit board (PCB) using wire bonding technology. The experiment results show that the sensitivities of the pressure sensor (a=0) and the acceleration sensor (p=0) are 1.0 mV/kPa and 0.92 mV/g at room temperature and operating voltage of 5.0 V, respectively. It indicates that the proposed sensor can achieve the measurement of applied pressure and acceleration, and has good sensitivity characteristics. Meanwhile the mutual interference of them is weak.