A method for selective ALD of ZnO on a wafer preparing a silicon wafer; patterning the silicon wafer with a blocking agent in selected regions where deposition of ZnO is to be inhibited, wherein the blocking agent is taken from a group of blocking agents includes isopropyl alcohol, acetone and deionized water; depositing a layer of ZnO on the wafer by ALD using diethyl zinc and H.sub.2O at a temperature of between about 140.degree. C. to 170.degree. C.; and removing the blocking agent from the wafer.