A trench-sidewall single-wafer-MEMS technology and its typical application in high-performance accelerometers

A trench-sidewall technology is developed for single-wafer-processed MEMS of in-plane lateral configuration. The technology is capable of integrating both piezoresistive/capacitive sensors and electrostatic actuators on trench-sidewalls. The developed technology has been successfully applied to a cantilever-shaped accelerometer with both piezoresistors and electrostatic self-testing electrodes integrated on the trench-sidewalls. Besides satisfactory electric principles of the trench-sidewall elements obtained, measurement results for acceleration sensing and electrostatic self-testing agree well with design.