Activation of Zr-Co-rare earth getter films: An XPS study

Thin films of non-evaporable getters are employed in the field of electronic devices packaging, as they provide a simple and effective solution for pumping in sealed applications. In particular thin films of Zr–Co–rare earth alloys deposited by sputtering have been developed for this purpose and successfully employed in industrial applications. In this paper we present an X-ray photoelectron spectroscopy investigation of the effect of thermal activation of the getter from the point of view of the induced surface chemical modification as seen by such a surface sensitive technique. We find that the activation process reflects in a clear reduction of Zr, accompanied by a decrease of the oxygen concentration at surface, which is fully accomplished already at 350 ◦C; while at 450 ◦C there is a significant increase of the cobalt concentration at surface.