We studied the structural and electrical properties of TiO 2 thin films grown by thermal oxidation of e-beam evaporated Ti layers on Si substrates. Time of flight secondary ion mass spectroscopy (TOF-SIMS) was used to analyse the interfacial and chemical composition of the TiO 2 thin films. Metal oxide semiconductor (MOS) capacitors with Pt or Al as the top electrode were fabricated to analyse electrical properties of the TiO 2 thin films. We show that the reactivity of the Al top contact affects electrical properties of the oxide layers. The current transport mechanism in the TiO 2 thin films is shown to be Poole-Frenkel (P-F) emission at room temperature. At 84 K, FowlerNordheim (F-N) tunnelling and trap-assisted tunnelling are observed. By comparing the electrical characteristics of thermally grown TiO 2 thin films with the properties of those grown by other techniques reported in the literature, we suggest that, irrespective of the deposition technique, annealing of as-deposited TiO 2 in O 2 is a similar process to thermal oxidation of Ti thin films.

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