Structural characterization of TiO2 films obtained by high temperature oxidation of TiC single crystals

The possibility of obtaining an oriented TiC-TiO2 junction was investigated. The (110) and (111) crystallographic planes of TiC were exposed to an Ar/O-2 stream with an oxygen content of 180 ppm at 815 degreesC. Through the oxygen consumption measurement, the oxidation kinetics were monitored both in non.-isothermal and isothermal conditions. The parabolic rate constants for the rutile growth on both the orientations of the TiC substrates were calculated. From their values, some information on the diffusion coefficient of the oxygen vacancies related to the oriented growth of rutile was also obtained, A detailed structural investigation was performed on TiO2 (rutile) grown on single crystal TiC substrates with different orientation. Environmental Scanning Electron Microscopy (ESEM), X-ray Diffraction (XRD) and X-ray Diffraction texture analysis techniques were utilized to obtain morphological and crystallographic information on the TiO2 films. Analysis of XRD spectra and XRD texture measurements show that growth of the TiO2 layers is strongly influenced by the crystallographic orientation of the substrate. A correlation between the crystal structure of TiO2 layers and the single crystal orientation of the TiC substrate is discussed in the paper. (C) 2002 Elsevier Science B.V All rights reserved.