Tin oxide thin films on Ag(111): Thickness and temperature dependent study of surface structure and electronic properties

Growth and structure of tin oxide films on Ag(111) from submonolayer to 10 monolayer equivalent thickness have been studied using low energy electron diffraction (LEED), x-ray photoemission spectroscopy (XPS) and angle-resolved photoemission spectroscopy techniques for room temperature (RT) and high temperature (HT) (573 K). For RT growth, most of the tin is oxidised to form tin oxide (SnOx) as confirmed by XPS where no metallic component is noticed. However, the grown films are not epitaxial or ordered which can be confirmed by no spots in LEED for higher coverage. Metallic Sn along with two oxidation states of Sn are noticed for HT growth, with the surface mainly composed of SnO2. LEED pattern shows the presence of c(2 × 2) and (3 × 1) along with two different hexagonal multidomain type patterns. The electronic structure for lower coverage resembled the Sn/Ag(111) alloy structures for lower coverage. For higher coverages appearance of three bands below 2 eV binding energy was noticed.