Blue Photoluminescence from Cerium Ions Doped Aluminum Oxide Films by Medium Frequency Reactive Magnetron Sputtering

摘要

Aluminum oxide film doped with Ce3+ have been deposited by the medium frequency reactive mag- netron sputtering technique. The photoluminescence emission from these films show peaks at range of 374-405 nm. The relative intensity of these peaks is strongly dependent on the amount of Ce incorporated in the films, and the temperature during deposition. The presence of Ce3+ as well as the stoichiometry of these films have been determi- ned by energy dispersive x-ray spectroscope (EDS) measurements. It is proposed that the light emission observed generated by luminescent center associated with cerium chloride molecular rather than to atomic cerium impurities. The reason for a dominance of the lower energy transition as the amount of Ce3+ in the oxide films is increased is that the energy difference of 4f1 and 5d1 decreases, with the increase of the Ce3+ concentration. The crystalline structure of the sample was analysed by x-ray diffractometry (XRD). Auger electron spectroscopy has been used to estimate the stoichiometry of the films. These luminescent films are potentially good candidates for photonics applications.