Growth of High-Quality (111) Oriented Cuprous Oxide Thin Films Oxidized in Water Vapor

High quality cuprous oxide thin films with large grain size were grown by thermal oxidation of copper foil in water vapor with N 2 gas. It was found that in water vapor (111) oriented Cu 2 O is preferentially formed, whereas mixtures of random oriented CuO and Cu 2 O are formed when oxidized in air. The effects of the film oxidation method and heating temperature are investigated. In addition, the optical band gaps of cuprous oxide thin films have been determined by measuring the transmittance and reflectance spectra.