Monolithic integration of a glass membrane on silicon micro-actuator for micro-interferometry

Abstract

We report the monolithic integration of glass membranes on a highly structured SOI wafer of electrostatic comb-drive actuator. The integration method combines glass micromachining techniques and non-standard processing of SOI, based on spray coating and projection photolithography. Proposed solution overcomes several basic difficulties of monolithic glass integration. We demonstrate its potential by fabrication of 4×4 matrix of reference mirrors on very thin (25 μm) and large (φ=2 mm) light-transparent glass membranes, which is of great importance for MOEMS-based phase-shift micro-interferometry systems.