Good luck Xiaojing, I saw someone else suggested adding SF6, I never tried
that.  I have etched SiO2 with PMMA mask with 100% SF6 and it was
consistently very clean, although you may have some selectivity requirements
that require you to use a carbon-containing etchant.  I have always liked
the idea of using SF6 etch and going with silicon nitride instead of SiO2.
Is that an option for you?, the SF6 etches nitride really fast and clean.

Take care,

Scott
----- Original Message -----
From: "Xiaojing Zou" 
To: "General MEMS discussion" 
Sent: Wednesday, August 16, 2006 2:07 PM
Subject: Re: [mems-talk] How to remove the PMMA etching residue.


> 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.
>