Plasma oxidation as a tool to design oxide films at low temperatures

Interfacial oxidation, an established approach to produce surface thin film s for catalysts, corrosion, ware protective coatings and electronic structu res is currently performed by thermal, anodic, and plasma methods. Fundamen tal physical-chemical models that can allow film design, particularly on al loys are lacking and plasma oxidation is the least studied of these methods . In this work, plasma oxidation of three CuZr alloys (CuZr2, CuZr, and CU5 1Zr14) has been studied using x-ray photoelectron spectroscopy and depth pr ofiling methods. The dependence of the resulting oxide film on alloy compos ition and sample temperature during plasma oxidation is investigated. In co ntrast to thermal and electrochemical oxidation which lead to the formation of a zirconium oxide film, plasma oxidation leads to the formation of a co pper oxide or metallic copper overlayer depending on temperature and copper concentration in the bulk. It is shown that plasma oxidation can be used t o design oxide films at room temperature, which require high temperatures u sing thermal oxidation and are not achievable by anodic oxidation. (C) 2001 American Vacuum Society.