Growth of Transparent Conductive Oxide ZnO Films by Atomic Layer Deposition

Abstract

ZnO films have been grown by atomic layer deposition (ALD) using diethylzinc (DEZn) and H₂O as reactant gases. Self-limiting growth occurred at substrate temperatures ranging from 105 to 165° C. Self-limiting growth was also achieved when the flow rates of DEZn and H₂O were varied. It was found that the orientation and surface morphology of the films were strongly dependent on the substrate temperature. A high electron mobility of 30 cm²/V·s was obtained for undoped ZnO films only 220 nm thick. The mobility of films was higher than that of films grown by MOCVD.