Reza, Two ways. One total vacuum dehydration before applying any one of a number of silane precursors for Parylene adhesion. Two replace Parylene with double silane coating that is far superior to Parylene for protection. Contact me directly for technical papers and reports. bmoffat@yieldengineering.com Bill Moffat -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of Reza Rashidi Sent: Tuesday, September 29, 2009 7:46 PM To: mems talk Subject: [mems-talk] parylene adhesion on Silicon Hi, I have a silicon wafer with a 5 um parylene on it which is a chemical protector. The package will operate at 170C and up to 300 psi in a basic solution. Due to poor adhesion of parylene, the liquid penetrates under the parylene film. I am wondering how I can increase the adhesion. Your advise will be appreciated. Thnaks, Reza