SOI wafer mold with high-aspect-ratio microstructures for hot embossing process

Abstract

This paper reports using a Silicon oil insulator (SOI) wafer as a mold insert for the hot embossing process on high-aspect-ratio microstructures to overcome two drawbacks of Inductive Coupled Etching (ICP) process, the area dependent etching and the micrograss. A thin sacrificial wall to eliminate the undercut in the big open area during ICP etching is also described. A good result of final embossed structure on PMMA with aspect ratio of 12 : 1, uniform thickness, and smooth surface is presented.