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.
[email protected] Bill Moffat

-----Original Message-----
From: [email protected]
[mailto:[email protected]] 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