Spectroscopic study of the surface oxidation of a thin epitaxial Co layer

We followed the surface oxidation of a 7-nm Co layer epitaxied on sapphire as a function of the oxygen coverage. Ultra-violet photoemission spectroscopy, atomic force microscopy and scanning tunneling microscopy were used to determine the thickness, surface roughness and electronic gap of the Co oxide. q2000 Elsevier Science B.V. All rights reserved