Abstract: A nano-polysilicon thin film pressure sensor is presented.Nano-polysilicon thin film is fabricated by LPCVD at a substrate temperature of 620℃,and then MEMS is adopted to fabricate four nano-polysilicon resistors with a film thickness of 63.0nm and mixed boron,so that a Wheatstone bridge can be formed and additional pressure can be measured.The experimental results show that when the thickness of the squared silicon membrane is 75μm and the constant voltage power supply of the nano-polysilicon thin film pressure sensor is 5.0V,the full range (160kPa) output is 24.235mV,the sensitivity is 0.151mV/kPa,the precision is 0.59%F.S,and the coefficient of zero temperature and sensitivity temperature are -0.124 and -0.108%/℃,respectively.

Key words: nano-polysilicon thin films,  MEMS technology,  pressure sensor,  temperature coefficient