STRUCTURAL AND ELECTRONIC-PROPERTIES OF VANADIUM ULTRA-THIN FILMS ON CU(100)

The growth mode, structural and electronic properties of vanadium ultr a-thin films deposited on Cu(100) at room temperature were studied by means of Auger electron spectroscopy, low energy electron diffraction and angular-resolved photoemission. The results of all measurements ar e consistent with a picture of simultaneous multilayer growth of vanad ium showing bcc-(110) structure. The normal emission UP spectra of the valence band region show a systematic increase of the intensity at th e Fermi level with the increasing vanadium concentration on the copper surface. There are two mechanisms which can account for this intensit y. In the limit of very small vanadium concentration, a vanadium virtu al bound state is probably a dominant contribution. At higher concentr ation, the quasi-3D-(110)-like structure is formed and the transition from the Sigma(q) band, lying just below the Fermi level, is the domin ant process contributing to the intensity at the Fermi level. Thermal stability of vanadium films and the copper segregation were also studi ed. (C) 1998 Elsevier Science B.V.