Evaluation of band gap energy and surface roughness for tin indium zinc oxide thin films by atomic force microscopy and electron spectroscopy

Abstract

The SnInZnO thin film was prepared at room temperature by RF magnetron sputtering. The band gap of this film was investigated by REELS and UV-Spectrometer analysis. The surface morphology and the root mean square (RMS) roughness of SnInZnO thin films measured using atomic force microscopy (AFM). By using REELS with low energy (500 eV) and high energy (1500 eV) electron beams, the surface band gap as well as and the bulk energy band gap were measured. In addition, the surface roughness was evaluated by atomic force microscopy. The result shows that the band gaps are affected by the primary electron energies. The transmittance value of 80% in the visible light region has been achieved. The optical band gap was calculated by using Tauc's relation from UV-Spectrometer analysis and compared to that of the band gap obtained by the REELS spectra.