Investigations of Co/Cu(110) by AES and DEPES

Auger electron (AES) and directional elastic peak electron spectroscopies (DEPES) were used to find the growth mode of Co on Cu(1 1 0) and the crystalline structure within the first few atomic layers. The Co growth at RT is characterized by the at first linear and then exponential decay of the Auger signal from the substrate hCu (CuM2,3VV, 66 eV). A detailed analysis of the Auger signal suggests that at an early stage of the Co growth the formation of the second layer occurs before the completion of the first monolayer. Further deposition leads to the simultaneous nucleation of subsequent layers before the complete covering of the substrate. The DEPES profiles recorded along the two Cu[1 0 0] and Cu [(1) over bar 10] azimuths at the primary electron beam energy Ep = 1.0 keV for equivalent quantities of 3ML and 5ML of Co show distribution of the intensity maxima similar to that for the clean Cu(1 1 0) sample, which indicates the epitaxial growth of Co. Theoretical DEPES profiles obtained by using the multiple scattering (MS) formalism at the maximal scattering order s = 3 reflect the intensity maxima associated with the < 100 >, < 110 >, < 112 > and < 111 > directions, as it was observed in experiment. (C) 2011 Elsevier B. V. All rights reserved.