I don't believe there are any photoresists that can withstand hot phosphoric
acid like you describe. Plasma etch works just fine. Bob Henderson

----- Original Message -----
From: "Sandip Agarwal" 
To: 
Sent: Tuesday, January 08, 2008 8:48 AM
Subject: [mems-talk] Etching silicon nitride

> I want to pattern silicon nitride by etching with hot phosphoric acid.
> What are the photoresists that would withstand these etching conditions?