Electronic structure of the Ti suboxide layer formed on a TiC(1 0 0) surface: Angle-resolved photoemission study

Angle-resolved photoemission spectroscopy (ARPES) utilizing synchrotron radiation has been used to study the electronic structure of a TiO-like layer formed on a TiC(1 0 0) surface. When the TiC(1 0 0) surface exposed to 500 L of O2 is heated at 1000 °C, a TiO-like layer with the thickness of 1.3–2.0 Å is formed on the surface. ARPES measurements show that the Ti 3d band and O 2p band are formed in the TiO-like layer at around the Fermi level and at 6–7 eV, respectively. Both bands show clear dispersions along both 〈1 0 0〉 ( Γ ¯ M ¯ ) and 〈0 1 1〉 ( Γ ¯ X ¯ ) symmetry directions of TiC(1 0 0), and the dispersive features are compatible with a (1 × 1) periodicity of TiC(1 0 0). These results are compatible with the model that the oxide layer is a well ordered TiO(1 0 0) film which is epitaxially grown on the TiC(1 0 0) surface.