A copper CMOS-MEMS Z-axis gyroscope

This paper reports the first thin film Z-axis gyroscope fabricated in a copper CMOS-MEMS process [5]. It works in the ambient pressure of 1atm and does not depend on Q enhancement. The sensor is integrated with the conditioning circuits in a commercial low-k digital copper CMOS process. The benefit of the copper CMOS-MEMS process includes high mass density and low stress. The device was fabricated in the UMC 0.18 mum six copper layer CMOS process with a dimension of 410 mum by 330 mum. It consists of an outer rigid vibrating frame and an inner accelerometer to detect the Coriolis force. Measured driving mode resonant frequency is 8.8 kHz, the sensitivity is 0.8 muV/degrees/sec and the noise floor is 0.5 degrees/sec/rootHz.