Band Gap Energy of SrTiO<sub>3</sub>Thin Film Prepared by the Liquid Phase Deposition Method

Gao, Yanfeng; Masuda, Yoshitake; Koumoto, Kunihito; Gao, Yanfeng; Masuda, Yoshitake; Koumoto, Kunihito

doi:2003.40.3.213

J. Korean Ceram. Soc. > Volume 40(3); 2003 > Article

Journal of the Korean Ceramic Society 2003;40(3): 213.
doi: https://doi.org/10.4191/kcers.2003.40.3.213

Band Gap Energy of SrTiO₃Thin Film Prepared by the Liquid Phase Deposition Method

Yanfeng Gao, Yoshitake Masuda, Kunihito Koumoto

Department of Applied Chemistry, Graduate School of Engineering, Nagoya University

ABSTRACT

Band gap energies of SrTiO$_3$(STO) thin film on glass substrates were studied in terms of annealing temperature. The STO thin film was fabricated by our newly developed method based on the combination of the Self-Assembled Monolayer(SAM) technique and the Liquid Phase Deposition(LPD) method. The as-deposited film demonstrated a direct band gap energy of about 3.65 eV, which further increased to 3.73 eV and 3.78 eV by annealing at 40$0^{circ}C$ and 50$0^{circ}C$, respectively. The band gap energy saturated at about 3.70 eV for the crystallized film which was obtained by annealing at 600-$700^{circ}C$. The relatively large band gap energies of our crystallized films were due to the presence of minor amorphous phase, grain boundaries and oxygen vacancies generated by annealing in air.

Key words: Band gap energy, Strontium titanate, Liquid Phase deposition, Crystallinity, Morphology