Characterization of InN films prepared using magnetron sputtering at variable power

Thin films of indium nitride were deposited on glass substrates using pulsed direct current (DC) magnetron sputtering with various power ranging from 100 W to 150 W. The X-ray diffraction (XRD) patterns of the deposited films revealed polycrystalline peaks of InN having preferred orientation towards the c-plane. The crystal quality of InN was significantly improved with increased sputtering power from 100 W to 130 W. However, with further increase in the power to 150 W, the crystallinity of the film decreased. The morphological results indicated agglomeration of smaller grains into larger ones with increasing power. The band gap and electrical resistivity of InN films decreased with increase of power to 130 W and then started to increase with further increase in the sputtering power. These results were associated with changes in the crystalline quality of InN at different sputtering powers. The optical properties of InN films have also been studied by the first principle approach to support our results about variation in band gap.