Effect of Substrate Temperature on Structural and Optical Properties of Nitrogen Doped SnO2 Thin Film

Abstract

Nitrogen doped SnO2thin films (thickness similar to 250 nm) were deposited at different substrate temperature by radio frequency (rf) sputtering method. Crystal structure, morphology and optical properties of these films were investigated by x-ray diffraction (XRD), atomic force microscopy (AFM) and UV-VIS-NIR spectrophotometer, respectively. XRD measurement suggests that the film deposited at room temperature was amorphous in nature and films deposited at higher temperature were crystalline in nature. The film deposited at RT and 200 degrees C have transparency more than 90% in visible region but the film deposited at 400 degrees C has lesser transparency. Red shift was observed in the absorption edge may be due to decrease in ionicity due tothe formation of the Sn-N bond.