From zywang at stanford.edu Mon Mar 15 16:44:59 2004 From: zywang at stanford.edu (Zhengyu Wang) Date: Mon, 15 Mar 2004 16:44:59 -0800 (PST) Subject: how to process double polished wafer in P5000? Message-ID: Hi, I am urgently looking for suggestions from experienced users who have successfully processed double polished wafers in P5000 before. In my case, I have double polished wafers (label read 300-375 micron thick), 1.5 micron nitride deposited on both sides. Then 1.6micron 3612 was coated on frontside, patterned, with edge bead removal. I also have 15 micron SPR220 coated on backside to protect it from scratching (around 15mm edge PR on backside was simutaneously removed during the edge bead removal process on the frontside). Then when I sent the wafer in chamber B for nitride etch, the wafer broke when the cooling helium was put on the backside. It seems when the wafer was clamped and put in vacuum, it cant stand the pressure of the cooling helium. Has anybody successfully processed double polished wafer in P5000 before? if so, could you please send me a note give me some tips on how to process this properly so the wafer wont break? I would really really appreciate any help! best regards, Zhengyu ----------------------- Zhengyu Wang Address: Telephone No.: McCullough building, (O) (650) 723-8654 476 Lomita Mall, (L) (650) 723-1112 Stanford, CA 94305-4045 No fate but what we make. -----------------------