dear all,

   i need etch Si substrate with KOH solution,but i found a 2000A-layer SiO2 by
thermal oxidization can't resist etch (about 100 minutes),so i have to deposite
a layer of Si3N4? Is there anything else ,which resists KOH while solutes in
organic solvent,such as  light-sensitive lacquer,or certain  kind of pastern
,can take the place of SiO2 or Si3N4?

Best Regards

anodle