Design and study of piezoresistive polycrystalline silicon sensor

Piezoresistive polycrystalline silicon sensor has the advantages of high sensitivity and nice stability as well as not hard to manufacture, so it is suitable for measuring the ultra-micro pressure. The mature polycrystalline silicon is adopted as sensitive material for the sensor in this paper. Two island-beam structure is used as the chip; stress dissipative structure has been designed; the mask structure is discussed in detail. The sensor can match the need of ultra-micro pressure measurement and overload protection. A detailed study of the structure is developed by the applications of finite element analyses (FEA) software. The study offers important reference to the optimization of the sensor chip. Finally, the paper studies the static and dynamic performance of the sensor. We find that the structure we designed here has good linearity, high overload protection and good sensitivity. It is suitable for measuring 500Pa micro pressure.