Nitrogen-Doped Titanium Dioxide and Cobalt Oxide Thin Films Prepared by Reactive Sputtering

Abstract

In the present work, reactive sputtering technique was used to prepare layers of nitrogen-doped titanium dioxide (TiO₂) and cobalt oxide (Co₃O₄) thin films on indium-tin oxide (ITO). Both materials showed polycrystalline structures. The Co₃O₄ samples showed polygon-shaped particles with apparent aggregation, while the TiO₂ samples showed approximately spherical particles with lower minimum size when compared to that of Co₃O₄ samples. The absorption of Co₃O₄ films was very sensitive to the variation of oxygen content in the gas mixture as the absorbance increased with increasing the oxygen in the gas mixture due to the increase in formation of the Co₃O₄ molecules. Energy band gap was shown dependent on the preparation conditions.