On the Ag and Au deposition on the Si (113)-1x1 surface: First principles studies

Silver (Ag) and gold (Au) deposition on the high index silicon (113) surface is investigated using ab-initio calculations, within the density functional theory (DFT). Ag and Au concentrations are varied from 1 atom up to 3 monolayers (MLs). The atomic structure stability is determined by applying the surface formation energy (SFE) formalism. When 4 metal atoms are deposited on the silicon surface, one possible stable atomic structure is the zigzag atomic wire formation, with the Au atomic wire being more stable. The 1, 2 and 3 MLs thin film form all stable structures, with those of Au displaying better energetic stability. Electronic properties are studied in terms of the density of states (DOS) and projected density of states (pDOS). Results of the zigzag atomic wires indicate that charge transport may take place mediated by the silicon atoms underneath the metal atoms. The metal structure formation on top of the Si (113)-1x1 may be applied in ohmic contacts, which may be used in the nano-electronic industry.