Fabrication and Characteristics of Silicon Bridge Magnetic Sensor Based on Nano-Polysilicon TFTs

Abstract:

A silicon bridge magnetic sensor based on nano-polysilicon TFTs is presented in this paper.It adopted four nano-polysilicon TFTs on the center of every squared silicon membrane edge to forma Wheatstone bridge, and then its squared silicon membrane center was sticked by ferromagnetic material.The sensor simulation was realized by adopting ANSYS software. The simulation results showthat based on the piezoresistive effect, the measurement to the external magnetic field can be achieved.According to the simulation results, we designed and fabricated the silicon bridge magnetic sensor byCMOS technology and MEMS technology. The experimental results show that when supply voltageof the sensor is 5.0 V, its full range (4.0 kGs) output voltage is 10.97 mV, and magnetic sensitivity is1.44 mV/kGs.

• Periodical: Key Engineering Materials (Volumes 609-610)
• Pages: 1100-1105
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.609-610.1100
• Online since: April 2014
• Authors: Xiao Feng Zhao, Tong Wu, Jing Ya Cao, Dian Zhong Wen*, Hong Quan Zhang, Cui Cui Zhuang, Yang Yu
• Keywords: ANSYS, Magnetic Characteristics, Nano-Polysilicon TFTs, Silicon Bridge Magnetic Sensor

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