Replication of optical MEMS structures in sol–gel materials

A replication method of fabrication for micro electro mechanical systems (MEMS) structures is presented, for use as an alternative to silicon processing. UV-curable ORMOCER® sol–gel is used as base material. The basic fabrication process involves deposition and patterning of a sacrificial spacer layer and a combined molding and photolithography step. This method allows creation of free-standing micro-mechanical elements with monolithic integration of high resolution micro-optical structures. Strain due to the shrinkage of the ORMOCER® sol–gel material during processing has been measured using test structures. Possible applications of this fabrication process are optical MEMS devices that incorporate lenses, diffractive optics or waveguides.