Thanks a lot.

I tried the recipe with CHF3:O2=10:1. It looks not very helpful. I see if
Shipley PRX solution works for me.


----- Original Message -----
From: "Scott McWilliams" 
To: "General MEMS discussion" 
Sent: Wednesday, August 16, 2006 9:15 AM
Subject: Re: [mems-talk] How to remove the PMMA etching residue.

> Hi Xiaojing, are you using CF4 and CHF3 without oxygen mixed in?  I have
> had difficult to remove polymers form using both CF4 and CHF3 while
> etching SiO2.  Can you reduce the selectivity to the PMMA a little bit and
> add some oxygen to the etch?  I have also had some success using Shipley
> PRX solution to remove the etch residue.  PRX does etch SiO2 very slowly
> but didn't matter on my application.
>