Structure and oxidation properties of CeN thin films prepared by DC reactive magnetron sputtering

Cerium nitride (CeN) is a material that can be used to simulate the properties of uranium nitride (UN). Study on the preparation, oxidation and antioxidant properties of CeN is significant and indispensable. CeN films were deposited on silicon (400) substrates by direct-current magnetron sputtering with mixtures of argon (Ar) and nitrogen (N2) as the working gas. Scanning electron microscopy, X-ray diffraction, white-light interferometry, and Auger electron spectroscopy were used to characterize the CeN films, including their surface morphology, structure, and element distribution. It is found the crystal structure was strongly affected by the deposition power and ratio of N2 to Ar. The brassy and metallic luster films with preferred orientation along (111) plane were obtained at the power of 200 W and the N2/Ar ratio of 2:18. The oxidation characteristics of the CeN films were investigated by exposing the samples to air. After exposure to air for half an hour, the CeN films showed signs of oxidation and cracking. The films became pulverized and detached from the substrate after one day of exposure to air. To avoid oxidation of the CeN films, their surfaces were coated with an aluminum protective layer, which played an important role to enhance film stability. This work provides a new platform to simulate the properties of UN.