Growth, structural evolution and electronic properties of ultrathin films of Sn on W(110)

Abstract

Growth and structure of Sn on W(110) from submonolayer to thick film (up to 8 monolayers) coverages at room temperature (RT) and as-well-as for higher temperatures (HT) (up to 673 K) have been studied using low energy electron diffraction (LEED), x-ray photoemission spectroscopy (XPS) and angle-resolved photoemission spectroscopy (ARPES) techniques. Surface structural evolution was studied where (3 × 1), (1 × 3) and (1 × 4) LEED patterns were observed for RT whereas (3 × 1) and (1 × 4) LEED patterns were observed for growth at 673 K due to the energetically available adsorption sites for Sn atoms on W(110) surface. The absence of alloy formation between Sn and W was confirmed by the XPS data where surface core level shift of Sn 3d was observed whereas no shift was observed for W 4f levels. Detailed electronic structures were studied along Γ¯ - H¯ and Γ¯ - N¯ directions for Sn deposited on W(110) with the help of ARPES. ARPES data for RT and HT case is mostly similar. A pair of splitted bands was observed due to the deposition of Sn near the surface projected band gap.