Viscous Hot Glass Forming for Optical Wafer Level Packaging of Micro Mirrors

MEMS mirrors are gaining considerable interest for consumer applications like embedded pico projectors in smartphones. The use of micro mirrors in mobile systems demands for a robust package that prevents the system from contamination by particles, gases or fluids. Appropriate optical packaging so far has been neglected in most published MEMS mirror developments. This paper describes a unique technology to fabricate glass packages on 8 inch wafers with inclined optical windows for MOEMS on wafer scale which avoids the occurrence of highly intense reflections of the incident laser beam in the projected images. The new viscous glass forming process enables the fabrication of glass devices with optical windows with oblique surfaces using bonded silicon-glass wafers.