Structural and Optical Characterization of Indium Zinc Oxynitride Thin Films

Indium zinc oxynitride (IZON) thin films were deposited on Si(100) substrates by RF reactive magnetron sputtering at different substrate temperature to study their structural and optical properties. All the films were deposited in a reactive atmosphere of nitrogen and argon. As precursor material, an IZO target (In2O3-ZnO, 90-10 wt%) with a purity of 99.99% was used. The crystalline structure of the films was analyzed by X-Ray diffraction technique (XRD), the deposited IZON thin films were practically amorphous with some polycrystalline contents for the films deposited at 100 °C and 300 °C. The refractive index and the extinction coefficient had been obtained from Spectral Ellipsometry (SE) analyses using the Classical and Adachi models, both results were qualitatively and quantitatively approximate. These optical results were analyzed and used to propose roughness values of the films surface, through of an appropriate proposal of the structure of the films. The roughness values obtained from optical models were compared with the morphological results studied by Atomic Force Microscopy (AFM), and the roughness values, obtained by direct and indirect measure, were consistent between them. The incorporated nitrogen reduced the typical crystallization of IZO and favored the deposition of transparent thin films with very flat surfaces, these results shows that the IZON has an ideal amorphous material for applications as conductive oxynitride layers.