Reliable low-cost fabrication and characterization methods for micromechanical disk resonators

A reliable low-cost method is developed to batch fabricate Micro-Electro-Mechanical Systems (MEMS) resonators with high yield. The key breakthrough in the fabrication process is one novel approach realized to effectively restrain electrochemical corrosion of polycrystalline silicon (polysilicon) electrically coupled with noble metals of MEMS devices by hydrofluoric acid (HF)-based solutions. In addition, this paper reports a novel measurement architecture based on a differential readout topology. The differential circuit proposed here can effectively suppress noise and feed-through current by common-mode rejection of the differential amplifier. This differential amplifier circuit configuration is also applied to build up a notch filter with high quality factor (24800).