Effect of annealing temperature on the structural and optical properties of Al-doped ZnO films by RF magnetron sputtering

The Al-doped ZnO (AZO) films were deposited on the glass substrates by RF magnetron sputtering. After the deposition, the films were annealed in N-2 at several temperatures from 500 degrees C to 800 degrees C for 60 minutes respectively. The crystal structures of the AZO films were characterized and analyzed by X-ray diffraction. The surface morphologies of the films were observed by SEM. The transmission spectra of the films were measured using a spectrophotometer within the range from 200 to 800 nm at room temperature. The results indicate each of the films has a preferential c-axis orientation and the grain size increases with annealing temperature increasing. All the films exhibit a high transmittance in visible region and have sharp ultraviolet absorption characteristics.