Electroplated nickel based micro-machined disk resonators for high frequency applications

Microelectromechanical system (MEMS) based resonators can be used for filtering and frequency synthesis applications in many subcomponents of radio frequency wireless integrated circuits due to their small size, high level of frequency selectivity, low cost batch fabrication, ease of integration with CMOS circuits. Electroplated nickel is an attractive low cost material for CMOS compatible MEMS due to their low deposition temperatures. Among the different modes of vibration, radial-contour mode resonators are preferred for high frequency applications because they offer higher effective stiffness. Two different types of electroplated nickel based radial-contour bulk-mode circular disk resonator geometries which depend on capacitive actuation and readout technique is presented in this work. Material, mechanical and electrical characterizations were performed on these structures to show their functionality.