The surface electronic structure and reactivity of the TiO thin film formed on a TiC(100) surface have been investigated using angle-resolved photoemission spectroscopy (ARPES), utilizing synchrotron radiation and ultraviolet photoemission spectroscopy (UPS). It has been found that the TiC(100) thin film is formed on the surface when the TiC(100) surface exposed to 500-1000 L of O-2 is heated at 1000 degreesC. ARPES measurements show that two-dimensional metallic states are formed in the TiO thin film. (C) 2004 Elsevier B.V. All rights reserved.