In-situ phosphorus doped ultra-high vacuum e-beam evaporated silicon for high gauge factor polysilicon

This paper reports a low temperature, high gauge factor polysilicon piezo-resistor fabricated by aluminium induced crystallization (AIC) process at 450oC. Through in-situ phosphorus doping of ultra-high vacuum e-beam evaporated amorphous silicon precursor, the gauge factor of the AIC polysilicon is increased from 38 to 56. This is a significant increase in its sensitivity, and the highest reported gauge factor under CMOS-MEMS compatible temperature range.