I am looking for a protective coating or tape to stand up to KOH for an
extended period. At the end of the etch my wafers are thin. I am
mostly concerned with the outer rim of the wafer, where even small
scratches become great cleavage planes.
I realize that there are a couple commercially available coatings, such
as Protec or BPR100. Does anyone know which ones are better for long
processing? Also, I am etching my wafer on both sides, so I can't spin
on a protective coating. I wonder if I can simply paint the edge of
the wafer with these coatings and then bake them. Will they still be
resistant to KOH?
Are there any other products or ideas that I should consider?
Thank you,
Arthur Beyder
SUNY at Buffalo