A new wet patterning technology which is particularly well suited to moisture resistant polyimides is described. The key feature is a two step wet-etch with the photoresist patterned and the amic acid etched in sequential steps. A higher degree of sidewall control than previously attained is possible because the etchant can be tailored specifically for the polyamic acid. The etchants operate by the polarity shift mechanism conventionally used to etch polyamic acids with hydroxide bases, but instead use the weaker aliphatic amines as the active base component. Alcohols are used to adjust the polarity of the solvent.