From tkramer at stanford.edu Tue Jun 6 14:20:40 2000 From: tkramer at stanford.edu (Theresa Kramer) Date: Tue, 6 Jun 2000 14:20:40 -0700 (PDT) Subject: Black Silicon Message-ID: Fellow Lam Users, Following the recent wet chamber clean in the lam, I am encountering Black Silicon* on wafers with 3612 resist and almost full resist coverage using etch program 25. This is a new resist configuration for me, so before we further chase chamber seasoning concerns, I was wondering if anyone else had this problem prior to the clean. Wafers with no resist are fine. I can't say what the status is now for wafers with sparse ebeam patterns, but they never used to have a problem. If you have used 3612 resist with almost full coverage to mask silicon using program 25 and either _have_ or _have not_ had problems with Black Silicon, please let me know. If this has been a continuing issue, then I will alter my process flow. If this is new, it obviously needs to be fixed. Thanks! Theresa *Black Silicon occurs from micromasking. The resist comes out fine, but any exposed silicon appears black due to light trapping. There is no way to "clean" it.