Nanosized TiO2 thin films were deposited by conventional vacuum thermal evaporation and triode-cathode sputtering of Ti on silicon and quartz substrates. To form TiO2 a high temperature annealing of the Ti films was carried out in the range of 450÷800 ºC. The optical properties of TiO2 were studied by measuring UV-VIS transmittance spectra and the indirect band gap was evaluated. Scanning electron microscope (SEM), atomic force microscope (AFM) and energy-dispersive spectroscopy were employed for surface and structure analysis. Structures for UV sensors were formed by thermal evaporation of various combing contacts on the TiO2/Si substrates. The photoresponse of the structures was detected in the wavelength range of 235÷420 nm. An increase in photocurrent with an order of magnitude was detected by exposing samples to UVA illumination and applying 6÷10 V bias voltage. The obtained results indicated that the studied structures are suitable for UV sensors.
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