Effect of substrate temperature on the structural, optical and electrical properties of Tin Oxide thin films

Interesting semiconductor materials of SnO2 thin films were deposited on the glass substrates heated at different temperatures from 300 to 450 degrees C. The structural, surface morphological, composition, optical and electrical properties of SnO2 thin films were investigated. X-ray diffraction showed that the obtained films were polycrystalline nature with cubic structure and were preferential oriented along the (100) direction. The surface morphology of the films was found to increase in size when the temperature is increased from 300 to 450 degrees C. The composition of these films was also confirmed by energy dispersive analysis by X-ray. Optical properties of the films showed high transmittance maximum at 450 nm for each spectrum is observed as about 82, 86, 87 and 89% respectively. Optical band gap energy was found to be increases from 3.52 to 3.65 nm for the SnO2 films heated from 300 to 450 degrees C. On the other hand, PL spectra of all films with a very sharp peak below 462 nm due to the presence of interstitial oxygen vacancies. Thus, the deposited material shows a potential application in SnO2 thin films and might be useful for gas sensor applications.