Image reversal on the first layer makes it impervious to most chemical reactions. The sensitizer is turned into acid then neutralized so developer does not affect it. As an example of its stability it will not flow at 400 degrees C. Contact me for free tests. Bill Moffat, CEO Yield Engineering Systems, Inc. 2185 Oakland Rd., San Jose, CA 95131 (408) 954-8353 -----Original Message----- From: Phillipe Tabada Subject: RE: [mems-talk] MEMS switch contact dimple Hi Erkin Look up processes involving UV hardening your PR and then placing it under elevated temperatures in order to crosslink the polymers. This should prevent the first layer of PR from dissolving when the second layer of PR is deposited. Phil Tabada