High-quality ZnO thin films prepared by two-step thermal oxidation of the metallic Zn

摘要

In this paper, we report the preparation of nanocrystalline ZnO thin films on Si(100) substrates using a simple method, in which a resistive thermal evaporation of Zn and a two-step annealing process were employed. The aim of the first annealing step in an oxygen ambient at 300 deg. C for 2 h is to form ZnO layers on the surface of the Zn films to prevent the diffusion of the metallic Zn from the films during the high-temperature annealing process. To obtain high-quality ZnO films, a high-temperature annealing step was performed at temperature in the range of 600-900 deg. C.