Hello all,
I am trying to etch Si using KOH. I tried various concentrations at
different temperatures and it looks 40% KOH [40gms KOH, 100ml water,
25ml IPA] at 80 degrees C works the best [15 mins of etching resulted
in a depth of 15um]. But i am unable to get a smooth surface. I see
black spots scattered all over the wafer. I was wondering if any of
you have experienced this before. Is there any other etchant or
another concentration of KOH that could be used as a 2nd step to
smoothen the surface, once the target depth is reached? Any
suggestions would be greatly appreatiated.

Thanks,
vinay