Properties of Au incorporated In2O3 films

Abstract

Effect of gold loading on the structural, morphological, optical and electrical properties of RF magnetron sputtered In2O3 films is discussed. Annealing is done to analyse the properties of heavily Au loaded In2O3 film after thermal treatment. Au acts as a nucleation centre and improves the crystalline quality of cubic bixbyite In2O3 films with moderate Au loading concentration. FESEM and AFM images of the as-deposited films present smooth surface morphology with a dense distribution of small grains. Random distribution of Au nanorods can be seen in the FESEM image of the 10 wt% Au incorporated film annealed at a temperature of 400 °C. The present study reveals the formation of smooth, crack-free, crystalline In2O3 films with Au incorporation. XPS analysis suggests the predominance of metallic state of Au in the Au loaded films. Absorption studies show an enhanced absorption in both as-deposited and annealed Au loaded films. Transmittance of In2O3 films is considerably modified but electrical properties are not much modified by Au incorporation. Enhancement in UV luminescence emission of In2O3 films ~378 nm is observed with Au incorporation up to 3 wt%. Intense UV emission in Au incorporated films opens a possibility of using these films for UV light emission applications.