Comparison of Two Alternative Fabrication Processes for a Three-Axis Capacitive MEMS Accelerometer

Tez S., Akin T.

26th European Conference on Solid-State Transducers (Eurosensors), Krakow, Poland, 9 - 12 September 2012, vol.47, pp.342-345 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 47
  • Doi Number: 10.1016/j.proeng.2012.09.153
  • City: Krakow
  • Country: Poland
  • Page Numbers: pp.342-345
  • Middle East Technical University Affiliated: Yes

Abstract

This paper presents a three-axis capacitive MEMS accelerometer implemented by fabricating lateral and vertical accelerometers in a same die with two alternative processes: a double glass modified dissolved wafer (DGM-DWP) and a double glass modified silicon-on-glass (DGM-SOG) processes. The accelerometers are implemented with a 35 mu m structural layer, and the three-axis accelerometer die measures 12mmx7mmx1mm in each process. Each process includes a second glass wafer which, not only allows implementing a top electrode for the vertical accelerometer, but also forms an inherent cap for the entire structure. Thanks to the stress-free structural layer coming from the SOI wafer, the DGM-SOG process allows obtaining the same rest capacitance values in each side of the accelerometer, which is one of the most important challenges for a functional high performance operation. (C) 2012 Elsevier Ltd....Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.