| AVS 62nd International Symposium & Exhibition | |
| Spectroscopic Ellipsometry Focus Topic | Thursday Sessions |
| Session EL+EM+EN-ThM |
| Session: | Spectroscopic Ellipsometry: Novel Applications and Theoretical Approaches |
| Presenter: | Junbo Gong, University of Science and Technology of China |
| Authors: | J.B. Gong, University of Science and Technology of China R.C. Dai, University of Science and Technology of China Z.P. Wang, University of Science and Technology of China Z.M. Zhang, University of Science and Technology of China Z.J. Ding, University of Science and Technology of China |
| Correspondent: | Click to Email |
SnO2, which is an n-type semiconducting material with a wide band gap 4 eV, is an interesting material due to its high electrical conductivity and optical transparency. SnO2 film is attractive for many applications such as optoelectronic devices, gas sensors, thin film transistors, transparent electrodes, anti-reflecting coating, and as catalyst support.
In this work, the ellipsometric parameters of SnO2 films on quartz glass are measured by spectra ellipsometer(J. A. Woollam M-2000U) in the wavelength range of 300 to 1000 nm at different temperature from room temperature to 600 oC. By using a semitransparent model, the precise thickness and optical constants of SnO2 thin film depending on the temperature were obtained and the evolution process was studied. The film thickness significantly decreased with increased temperature from 100 oC to 300 oC and the absorption edge has an obvious blue shift which means an increased band gap. The result reveals that this process is not reversible. Combined with XRD measurement, we identified that the change of thickness and optical properties of SnO2 film was due to a phase transition from rutile structure to columbite structure.