This work aims to design a novel monolithic accelerometer on (111) substrate. A new micro fabrication process is proposed to integrate the electrode and spring-mass system on single wafer without bonding process. This accelerometer has spring with high aspect ratio and large lump mass, which can produce pure in-plane motion. In order to get large capacitance variation, a new design of differential electrode was also proposed. This comb-shape electrode also plays as mask for metal deposition. Furthermore, this process needs only two masks to define spring-mass system and electrode from front side and backside respectively. Anisotropic etching is then used to separate mass from electrode. This step forms a surrounding gap to the opening of the top layer, which insulates top and bottom electrodes automatically.

Date Published: 21 November 2001
PDF: 7 pages
Proc. SPIE 4592, Device and Process Technologies for MEMS and Microelectronics II, (21 November 2001); doi: 10.1117/12.449000

Published in SPIE Proceedings Vol. 4592:
Device and Process Technologies for MEMS and Microelectronics II
Jung-Chih Chiao; Lorenzo Faraone; H. Barry Harrison; Andrei M. Shkel, Editor(s)