ELECTRICAL-PROPERTIES OF TIO2-X THIN-FILMS BY THERMAL-OXIDATION

The electrical properties of the TiO2-x thin films prepared by thermal oxidation from titanium sheets have been studied. The films by water vapor oxidation are oxidized more homogeneously than those by air oxid ation. The electrical contact to measure the electrical conductivity o f the TiO2-x electrodes is improved when the electrode surface is plat ed with silver. The hysterisis of the electrical conductivity curves i s improved by applying alternating current rather than direct current on both sides of the electrode. The observed energy gap, E(d) are 0.05 -0.16 and 0.11-0.76 eV, respectively, at low and high temperatures reg ion. These values of the TiO2-x electrode prepared by water vapor oxid ation are similar to those of single crystal TiO2. The values of donor concentration, N-D, are observed about 10(15)-10(19) and 10(17)-10(21 ) cm(-3), respectively, at low and high temperatures region. These val ues obtained at high temperature region are consistent with the values obtained from Mott-Schottky plot.