[mems-talk] Hillrocks Generated during TMAH Etching

[李科佳]

Hello all,

I am using TMAH for etching silicon (100) plane. And it found that the
etched (100) plane was covered by a number of pyramidal hillocks. The TMAH
is 25 wt % solution and the temprature is 80 centigrade. Accroding to the
previous paper, the pyramidal hillocks only happened when the concentration
of TMAH was below 15 wt%. Meanwhile many researchers found that very smooth
surfaces were obtained above 22 wt % solution and no one has reported the
hillocks were observed in 25 wt % solution.

I am really confused about that. I don't know if I have done something wrong
in the experiment. Any help you can offer would be greatly appreciated.
Thank you!

Best regards!

Kejia Li
likejia at gmail.com