Low-voltage vibration sensor in standard CMOS process

A novel micro-vibration sensor with MOS structure is proposed and two solutions to reduce high threshold voltage are developed. The proposed sensor exhibits prefect linearity up to 99.98% and high resolution of 0.19 muA/g. The vibration sensor can provide various potential applications, such as civil structural health monitoring, biomedical applications, low power consumption wireless sensor networks. The Sensor is designed with commercial standard 0.25 mum CMOS process followed by only one maskless post-CMOS step. Gas rarefaction effect in ultra-thin air gap is also discussed in this paper.