Degradation Mechanism of Piezoresistive Sensors Under the Influence of γ -Ray Irradiation

Micro-electromechanical systems (MEMS) technology-based piezoresistive technique is a highly matured transduction technique. It is very popular for the MEMS devices used in various industries such as automotive, process control, aerospace and avionics, consumer electronics, nuclear power plants, and many more. MEMS pressure sensors are one among them, and their deployment in nuclear power plants and aerospace are prominently increasing. Hence radiation-induced performance degradation of piezoresistive pressure sensors has been carried out, which is a prime concern for such industries. Therefore, a set of experiments for the investigation of irradiation-driven performance degradation of MEMS pressure sensors are performed under varying doses of gamma radiations. An insignificant change in sensitivity was recorded which degraded up to a maximum of 0.78%, while the linearity remained unchanged for a cumulative dose of 27.90 Mrad. However, the deviation in the offset voltage of the Wheatstone bridge (WB) configuration was significant and as recorded was 139% at a cumulative dose of 27.90 Mrad. This article explains the degradation mechanism of MEMS piezoresistive sensors using the experiments and TCAD simulations.