Influence of Al-doping and oxygen partial pressure on the optical properties of ZnO films
Al-doped ZnO (ZnO:Al) thin films were deposited on glass substrates using the radio frequency reactive magnetron sputtering technique. The effects of Al concentrations and oxygen partial pressures on the microstructurc and the luminescence properties of the ZnO:Al thin films were studied. The results show that the crystallization of the film is promoted by appropriate Al concentration and oxygen partial pressure. Strong blue peaks located at 436 nm and weak green peaks located at about 495 nm and 530 nm were observed from the photoluminescence spectra of the samples. In addition, absorption properties of the samples were studied by UV spectroscopy. The optical band gaps calculated based on the quantum confinement model are in agreement with the experimental values.
