Optical and structural properties of nanocrystalline copper oxide thin films prepared by activated reactive evaporation

Abstract Nanocrystalline Cu 2 O thin films have been synthesized using an activated reactive evaporation technique. Structural and optical characterizations of these films have been carried out using: glancing angle X-ray diffractometer; Fourier transform infrared spectrometer; transmission electron microscope; and UV-VIS-NIR spectrophotometer. The nanocrystallite size in these films was varied by varying deposition parameters. Optical studies show a direct allowed transition and a shift in the optical absorption edge from the bulk value with nanocrystallite size and stoichiometry of these films. These results show that single phase nanocrystalline Cu 2 O thin films can be synthesized at a relatively low substrate temperature using the activated reactive evaporation technique. These studies indicate that nanocrystallinity results in the stability of cubic Cu 2 O phase in these films.