Hi Sebastian How about ALD deposited Al2O3, it is deposited at low temperature, conformal and the etch-rate in silicon DRIE is very low. If I'm correct, selectivities of 1:10000 are reported. Kind regards, Henk van Zeijl Delft University of Technology / DIMES POBox 5053 NL-2600 GB DELFT The Netherlands phone: ++31 15 2781092 fax: ++31 15 2787369 Email: h.w.vanzeijl@dimes.tudelft.nl http://www.dimes.tudelft.nl -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of Sebastian Sosin Sent: 13 November 2008 15:38 To: mems-talk@memsnet.org Subject: [mems-talk] etch stop layers fro silicon DRIE Does anyone have any knowledge of other etch stop layers for silicon DRIE, besides SiO2 and Al? We have an Adixen system and for my process it would save extra work to have something else as etch stop layer (not Al or SiO2). Sebastian Sosin