Titanium Silicide Formation on Oxidized Si(001)-2×1 Studied with Scanning Tunneling Microscopy and Scanning Tunneling Spectroscopy

Abstract

  Influence of the oxygen on island formation of titanium silicide on a Si(001) surface was studied by means of scanning tunneling microscopy to analyze the fundamental process of Metal-Oxide-Semiconductor (MOS) fabrication at the atomic scale. The shape of the nanoclusters differs from that formed without the oxide layer. The process is affected by desorption of SiO occurring at relatively lower temperature, while oxygen remains inside the silicide. With tunneling spectroscopy, the most of the clusters were identified to be crystallized in C49-TiSi₂ even at 1073 K, indicating that transformation to C54-TiSi₂ was disturbed by the presence of oxygen.