Growth and crystalline structure of Au layers on Ni(1 1 1)

Abstract

We present the results of investigations concerning the growth and crystalline structure of Au layers deposited on the Ni(1 1 1) surface at RT obtained with the use of Auger electron spectroscopy (AES) and directional elastic peak electron spectroscopy (DEPES). For clean Ni(1 1 1) experimental DEPES profiles exhibit intensity maxima corresponding to the close packed rows of atoms. Theoretical DEPES scans were obtained with the use of single scattering cluster (SSC) calculations by means of phase shifts, inelastic mean free paths and scattering cross-sections. A good correspondence between experimental and theoretical scans was obtained for the [ 2 1 ¯ 1 ¯ ] and [ 1 1 ¯ 0 ] azimuths of the Ni(1 1 1) surface. Auger peak kinetics recorded during continuous Au deposition suggests the formation of a flat Au layer till 0.54 ML and then the simultaneous growth of a few layers. Very low intensity reflections and considerable background intensities were found in the LEED patterns, which indicate a weak long-range order in the adsorbate. DEPES profiles obtained for 8 ML of Au on Ni(1 1 1) reflect a short-range order in the adsorbate. Intensity maxima observed in DEPES profiles are characteristic of two mutually rotated Au(1 1 1) domains. Domain populations were found by an R-factor analysis giving n ¯ 1 = 49 ± 2 % for rotated and n ¯ 2 = 51 ± 2 % for unrotated domains.