Yes, through the wafer, 525 microns deep __________________________________________________________________ Sebastian Sosin -----Original Message----- From: 汪飞 [mailto:wangfeiustc@gmail.com] Sent: Friday, November 14, 2008 1:58 PM To: General MEMS discussion Subject: Re: [mems-talk] etch stop layers fro silicon DRIE Do you want etch through a wafer?