Dear MEMS research,
when TMAH or EDP used as an etchant, and  SOI 40 um wafer was used, I
figured out that the etch stop and it didn't hit the buried Silicon dioxide
and a layer with thickness  based up on SEM photo ~10-15um, do you have any
idea about this issue , if so would you please tell me what this layer is,
and how can we get rid of it, and  really I appreciate  if you tell me about
the reason that causes this layer.
thanks a lot.

BigBangwidth
the exabit netOpticalTM company

Abdullah Tashtoush
MEMS Process Engineer
Tel: (780) 490-4800 Ext. (227)
Cell:(780) 953-0702
Fax: (780) 430-8545
atashtoush@BigBangwidth.com
www.BigBangwidth.com