Hi,

Is there any simple way to check if holes are fully etched in DRIE
process or not.

I have one thin wafer 250 micron bonded with another wafer 450 micron.
I am trying to achieve through holes in first Si wafer(min hole dia is
30 microns), but my lab does not have any instrument to check if holes
are fully etched or not.

I have to stop DRIE process, then have to remove wafer and then again
have to bond wafers to check the etched holes thickness. (whole
process 2-3)

I will thankful to any one who can let me know any method to check it.


--
Thanks,
Pradeep Dixit
Research Student,
Micromachine Center,
NTU Singapore - 639669