Protective layer formation during oxidation of CuAu(100) using hyperthermal O molecular beam

Okada, Michio*; Hashinokuchi, Michihiro*; Fukuoka, Masayuki*; Kasai, Toshio*; Moritani, Kosuke*; Teraoka, Yuden

Applied Physics Letters, 89(20), p.201912_1 - 201912_3, 2006/11

https://doi.org/10.1063/1.2390672

Oxidation of CuAu(100) using a hyperthermal O molecular beam (HOMB) was investigated by X-ray photoemission spectroscopy in conjunction with a synchrotron light source. From the incident energy dependence of the O-uptake curve, it was determined that the dissociative adsorption of O implies a higher activation barrier and therefore less reactivity due to the Au alloying. The dissociative adsorption progresses with the Cu segregation on the surface. No prominent growth of CuO even for 2 eV HOMB suggests that the Au-alloying of Cu can serve as a protective layer against further oxidation into the bulk.