Improved anti-stiction coating of SU-8 molds

Abstract

We have developed a simple method for the improved release of embossed poly(methyl methacrylate) (PMMA) as well as casted poly(dimethyl siloxane) (PDMS) from a SU-8 mold using vapor phase deposition of 1H,1H,2H,2H-Perfluorodecyltrichlorosilane (FDTS). We have further investigated if prior breakage of the epoxy groups by oxygen plasma or sulfuric acid improves the deposition of FDTS. The deposition of FDTS on acid-activated and untreated SU-8 gave an identical well performing anti-stiction coating, as opposed to oxygen plasma activated surface which resulted in a poor FDTS coverage. In this paper the method for the mold fabrication as well as the vapor phase deposition of FDTS onto the mold is described; examples of released final devices using this method in PMMA and PDMS are presented. (C) 2010 Elsevier B.V. All rights reserved