Vapor-phase self-assembled monolayer on SU-8 cantilever for explosive sensing

This paper reports novel technique of coating SU-8 cantilevers with self-assembled monolayer of Zinc porphyrin in vapor phase. Porphyrins have been reported to be effective for explosive detection, though incorporation of its thin films on polymer cantilevers is difficult due to harsh solvents of porphyrin which damage the polymer layers like SU-8. Hence a nondamaging process which is also industry friendly and useful for mass production is required. The vapor phase technique developed here to deposit self-assembled monolayers (VPSAM) of Porphyrins is a MEMS/CMOS compatible process which opens up a whole new set of opportunities. In this paper, we discuss the process of VPSAM and show its application in explosive detection of nitro-based explosives (PETN, RDX, TNT).