Electrical and optical properties of Bi2Ti2O7 thin films prepared by metalorganic decomposition method

摘要

Highly (111) oriented Bi2Ti2O7 thin films have been grown on Pt/Ti/SiO2/Si and Al2O3 substrates by metalorganic decomposition method at 550degreesC. The structural properties of the films were examined by x-ray diffraction. The Bi2Ti2O7 films exhibit good insulating property and the leakage current density of the film on Pt/Ti/SiO2/Si is only about 1.56x10(-8) A/cm(2) at 200 kV/cm. The refractive index and extinction coefficient of Bi2Ti2O7 thin films were determined by fitting the infrared spectroscopic ellipsometric data using a classical dielectric function formula. As the wavelength increases, the refractive index decreases, while the extinction coefficient increases. And the band-gap energy E-g was obtained from the optical transmission spectra of Bi2Ti2O7 thin films. (C) 2004 American Institute of Physics.