The temperature dependence of CU sub(2)O formation on a Cu(110) surface with an energetic O sub(2) molecular beam

We report a study of the surface temperature (T sub(s)) dependence of Cu sub(2)O formation on a Cu(110) surface induced by a hyperthermal O sub(2) molecular beam (HOMB), using x-ray photoemission spectroscopy in conjunction with synchrotron radiation. From the T sub(s) dependence of the O uptake curves, the direct dissociative adsorption process mainly contributes to the formation of the p(2 x 1)-O structure with an O coverage ([Theta]) of 0.5 ML for 2.2 eV HOMB incidence. On the other hand, the rate of oxidation at [Theta] > 0:5 ML, particularly in CU sub(2)O formation, strongly depends on the T sub(s). Thicker CU sub(2)O islands were found inhomogeneously at 400 and 500 K, suggesting the dominant role of the migration of Cu atoms in the CU sub(2)O formations on the Cu(110) surface.