文摘
The electronic and optical properties of GaInZnO (GIZO), HfInZnO (HIZO) and InZnO (IZO) thin films on glass substrates were investigated using X-ray photoelectron spectroscopy (XPS) and reflection electron energy loss spectroscopy (REELS). XPS results show that HIZO, GIZO, and IZO thin films have mixed metal and oxide phases. REELS spectra reveal that the band gaps of GIZO, HIZO, and IZO thin films are 3.1 eV, 3.5 eV, and 3.0 eV, respectively. These band gaps are consistent with optical band gaps determined by UV-Spectrometer. The optical properties represented by the dielectric function ?, the refractive index n, the extinction coefficient k, and the transmission coefficient T of the GIZO, HIZO and IZO thin films were determined from a quantitative analysis of REELS spectra. The transmission coefficient was increased by 4 % for the HIZO compound incorporating Hf into IZO, but decreased by 3 % for the GIZO compound incorporating Ga into IZO in the visible region in comparison to that of IZO.