DESIGN, FABRICATION, MODELING AND CHARACTERIZATION OF ELECTROSTATICALLY-ACTUATED SILICON MEMBRANES

• Main Author: Stahl, Brian C
• Format: Others
• Published: DigitalCommons@CalPoly 2008
• Subjects: MEMS; membrane; etching; microfabrication; silicon; Materials Science and Engineering; Semiconductor and Optical Materials
• Online Access: https://digitalcommons.calpoly.edu/theses/90; https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1098&context=theses

This thesis covers the design, fabrication, modeling and characterization of electrostatically actuated silicon membranes, with applications to microelectromechanical systems (MEMS). A microfabrication process was designed to realize thin membranes etched into a silicon wafer using a wet anisotropic etching process. These flexible membranes were bonded to a rigid counterelectrode using a photo-patterned gap layer. The membranes were actuated electrostatically by applying a voltage bias across the electrode gap formed by the membrane and the counterelectrode, causing the membrane to deflect towards the counterelectrode. This deflection was characterized for a range of actuating voltages and these results were compared to the deflections predicted by calculations and Finite Element Analysis (FEA). This thesis demonstrates the first electrostatically actuated MEMS device fabricated in the Cal Poly, San Luis Obispo Microfabrication Facility. Furthermore, this thesis should serve as groundwork for students who wish to improve upon the microfabrication processes presented herein, or who wish to fabricate thin silicon structures or electrostatically actuated MEMS structures of their own.