A sub-1G CMOS-MEMS accelerometer

We report experimental evaluation results of a CMOS (complementary-metal-oxide semiconductor)-MEMS (microelectromechanical systems) accelerometer for sensing sub-1G (1G = 9.8 m/s²) acceleration. The sub-1G MEMS sensor has been successfully implemented on a 180-nm CMOS LSI (large scale integrated circuits) for the first time. For the MEMS fabrication, we utilized multi-layered metal technology for the post-CMOS process. The accelerometer was developed within the footprint of 4 × 4 mm². The sensitivity was measured to be 0.604 (V/G) at the input of acceleration from -1 G to +1 G. The experimentally obtained results were consistent with the design values.