Pyramids on 111sidewalls when etching 100 Si in KOH
GARCIA BLANCO Sonia
2005-11-24
Hi!!
I am working in etching of silicon using KOH+IPA. I have oriented my
structures along the 110 plane direction (perpedicular to the flat) and I
obtain walls at 54.7 degrees. I assume that they are the 111 planes of
silicon.
My problem is that on these planes I observed the formation of pyramids. I
have used strong stirring and ultrasounds. I also tried using surfactants
(Triton-x-100). But I am always obtaining these structures.... I havent seen
pyramids like that on the papers so I was wondering if somebody has had this
experience before and how did they manage to get rid of the pyramids..... I
was supecting that it could be some etch of the 111plane, maybe the 122
planes?? but I dont know how to avoid them appearing.
Thanks a lot for your help!
Have a nice afternoon!
Sonia.