Effect of annealing temperature on the structural and optical properties of SnO2 thin films elaborated by sol-gel technique

In this study, the influence of annealing temperature on the structural and optical prop- erties of SnO2 thin films was investigated. SnO2 thin films were prepared by sol-gel deposi- tion on glass substrates at room temperature and then annealed at different temperatures (300, 400 and 500 degrees C) in air fortwo hours. The obtainedfilmswere characterizedby Raman spectros- copy and UV-Vis spectrophotometry techniques. A single-phase rutile structure was revealed by Raman spectroscopy analysis. The optical measurements have shown that all the films have a high transparency (75-85%) in the visible spectral range, and the optical band gap increases from 3.68 to 3.89 eV with increasing annealing temperature.