CHARACTERIZATION OF SILICON SURFACE MICROMACHINED MEMS DEVICES

Abstract

This paper introduces silicon surface micromachined devices, and primarily focuses on the characterization of a silicon-surface gyroscope and a laterally isolated accelerometer. Unlike most micromachined gyroscopes that consist of a single resonator, this gyroscope takes advantage of two oscillating structures to increase its mechanical sensitivity. The first structure is the resonator and the other structure is the sensing structure. Since the primary structure is much more massive compared to the secondary structure, the Coriolis deflection experienced by the primary structure during sensing will be transferred and magnified by the secondary structure. This self-amplified mechanical sensing increases the vibratory gyroscope's mechanical sensitivity. In comparison to the gyroscope, the accelerometer isolation. The accelerometer is noted to be fabricated using single crystal silicon structures and has high yield. Apart from the device mechanisms, this paper will cover the surface micromachining processing of these devices. In addition, this paper also summarizes the post-processing steps such as dicing and release processes needed to produce a working device. Finally, characterization techniques will be presented and results for the gyroscope and accelerometer devices will be presented in the remainder of this paper.