Abstract
The dc sputtering technique was used to deposit Al2ZnO4 thin films. X-ray diffraction (XRD) of as-prepared aluminum zinc oxide Al2ZnO4 thin films showed that the films showed amorphous nature, whereas, the annealed films showed some crystallinity with amorphous background. The optical constants such as the refractive index n, the absorption index k, and the absorption coefficient alpha of Al2ZnO4 thin films were determined using spectrophotometric measurements of transmittance and reflectance in the spectral range from 200 to 1200 nm. The maximum value of the transmittance were in the range from 85% to 90% depending on the condition of preparation. Furthermore, the effect of both thickness and annealing temperature on optical energy gap E-op, width of the band tails of the localized states E-u plasma frequency omega(p), and relaxation time tau of the carriers were studied. The allowed indirect optical energy gap found to be around 3.5eV.