Hi All, I am looking for an echant(wet) that etches silicon without differentiating between doped(p) and undoped areas. I tried various concentrations of KOH(20% to 50%) and it seemed like higher concentrations is the way to go. But on closer observation, realized that even at higher concentrations, the etch rate of undoped Si is very high compared to the doped areas. Any suggestions is greatly appreatiated, Thanks, Vinay