Analyses of piezoresistive and mechanical characteristics of nano polysilicon film

In order to take good advantage of nano polysilicon film, piezoresistive and mechanical characteristics of the nano polysilicon film are very necessary to investigated. In this paper, the nano polysilicon films were prepared by low pressure chemical vapour deposition under different technical parameters, including thickness, deposition temperature and doping concentration, which are very important for preparation of the nanofilm. The experimental results of piezoresistive and temperature characteristics show that the optimized technical parameters are followed, the thickness is about 90nm, the deposition temperature is 620°C, and the doping concentration is about 4.1×10¹⁹ cm^-3 or between 2.0×10²⁰ cm^-3 and 4.1×10²⁰ cm^-3 from different point of view. The experimental results of Young's modulus show that the mechanical characteristic of nano polysilicon film is almost independent of thickness. The piezoresistive performance of nano polysilicon film is better than that of single silicon under same doping concentration. The investigation of piezoresistive and mechanical characteristics of the nano polysilicon film is very useful for application of piezoresistive sensor, which can be used in the internet of things.