Abstract: The micro-sensor, a key component of gyroscope and comprising the hemisphere and hemi-circular ring coated with~2μm thick diamond coatings, was fabricated in conventional micro-electro mechanical system (MEMS) technology, including but not limited to the fabrication of concave Si-molds in hemi-sphere/hemi-circular ring shapes, thin film deposition, lithography, deep reactive ion etching, wet-etching, chemical-mechanical polishing.The influence of the conditions in each MEMS steps was investigated with scanning electron microscopy, Raman spectroscopy and in Matlab simulation to optimize the fabrication conditions.The preliminary results show that the six variables, including the Si-substrate orientation, concentration ratio of HF:HNO₃:CH₃COOH, mask-opening diameter, churning speed, etching temperature/time all have a major impact.Well-defined high quality hemispheres and hemi-circular rings of the resonator were fabricated under the optimized conditions.