TCR of the Ni-Cr Thin Film Resistors Used in Piezoresistive Pressure Sensor

摘要

In this paper,temperature characteristic of Ni-Cr thin film resistors is studied which have a low temperature drifting coefficient and used in a kind of metal piezoresistive pressure sensors based on MEMS technology. Normally, Ni-Cr alloys have a small temperature coefficient of resistance (TCR) compared with some other metal materials. But it depends on the composition of Ni and Cr in the alloy and on the annealing process under different temperature. Through the research of the effect of the composition of the alloy and annealing cycles, it is found that 50:50wt% Ni-Cr thin film has negative TCR and 80:20wt% NiCr thin film has positive TCR. Both of them have a small TCR and can improve the precision of piezoresistive pressure sensor.