Post-release capacitance enhancement in micromachined devices

This paper reports a novel design concept that aims to increase the detection and actuation capacitances in micromachined devices beyond the fabrication process limitations. The approach is based on designing the stationary components of the electrodes attached to a moving stage that permanently locks into the desired position before the operation of the device, to minimize the electrode gap with a simple assembly step. The concept has been implemented in bulk-micromachined prototype gyroscopes, and the experimental results have successfully demonstrated the feasibility of the assembly concept. It is experimentally shown that over an order of magnitude of capacitance increase is achieved in the same foot-print of the device, without additional fabrication steps.