Thanks a lot for your information.

Since you have experience in this case, I'd like to ask more about the
etching process. What is the RF power do you use ???
I found some group use 300-500 W high power, while others use 25W.   Do you
know what is the difference between them???


----- Original Message -----
From: "Mathieu Foquet" 
To: "General MEMS discussion" 
Sent: Thursday, September 21, 2006 1:09 PM
Subject: RE: [mems-talk] Dry etch selectivity between Al and PMMA


I did something similar to that a long time ago. Selectivity is around
2:1 (PMMA to Al). So it is not very good, but you should be fine for
what you are looking for. Selectivity improves a little by introducing
either some CH4 in the chamber.

You'll have to time your etch carefully though.