Fabrication of SiCN ceramic MEMS using injectable polymer-precursor technique

In this paper, a novel and cost-effective technology for the fabrication of high-temperature MEMS based on injectable polymer-derived ceramics is described. Micro-molds are fabricated out of SU-8 photoresist using standard UV-photolithographic processes. Liquid-phase polymers are then cast into the molds and converted into monolithic, fully-dense ceramics by thermal decomposition. The resultant ceramic, based on the amorphous alloys of silicon, carbon and nitrogen, possess excellent mechanical and physical properties for high-temperature applications. This capability for micro-casting is demonstrated in the fabrication of simple single-layered, high aspect ratio SiCN microstructures. A polymer-based bonding technique for creating more complex three-dimensional structures is also presented.