Uniform Sputtered Metallic Coatings on Silica Glass Micro Shell Resonators

This paper reports an improved magnetron sputtering method by using a multi-dimensional motion platform. Silica glass micro shell resonators fabricated by chemical foaming process are coated by traditional and multi-dimensional sputtering. The uniformity of Cr/Au metal film is characterized by Focused Ion Beam (FIB) and Scanning Electronic Microscopy (SEM). The results indicate that by applying multi-dimensional sputtering method, film thickness on the shell rim is more uniform with 5nm deviation. The resistance distribution in the circumferential direction of the resonator after coating is basically consistent and the coefficient of variation (COV) of resistance is 0.073.