Microelectromechanical resonator manufactured using CMOS-MEMS technique

The fabrication of a microelectromechanical resonator using the commercial 0.35 mu m complementary metal oxide semiconductor (CMOS) process and a post-process has been implemented. The resonator requires only one wet etching post-process. The suspended structures in the resonator consist of a membrane and four beams. The post-process utilizes an etchant to etch the sacrificial layer, and to release the suspended structures. Easy execution and low cost are the advantages of the post-process. The resonator comprises a driving part and a sensing part. The sensing part produces a change in capacitance when applying a driving voltage to the driving part in the resonator. A circuitry is used to convert the capacitance variation of the sensing part into the voltage output. Experimental results show that the resonant frequency of the resonator is about 39.5 MHz and the quality factor is 806. (C) 2007 Elsevier Ltd. All rights reserved.