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Titanium dioxide thin films have been prepared from the solution of TTIP (Titanium Tetra Isopropoxide), Acetic acid and Ethanol on the glass substrates by sol-gel spin coating technique. In the present work, the TiO 2 thin films have been analyzed for different coating cycles which were annealed at 450° C for one hour. The annealed films were characterized by X-Ray diffraction (XRD) method, UV-Visible & Photoluminescence (PL) spectroscopy, Field Effect Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray Analysis (EDAX).The XRD results show that the crystallite size increases from 6.3 nm to 35.5 nm with increase in number of coating cycles. The transmittance of the film and the optical band gap are found to decrease with increase in number of coating cycles. The room temperature PL spectra of TiO 2 thin films show blue and green emissions at 485 nm and 530 nm with excitation at 410 nm. The surface morphology shows rough surface with irregular particles. The stoichiometric ratio of the film was confirmed by EDAX analysis. The results of structural and optical characteristic study suggest that the sol-gel spin coated nanocrystalline TiO 2 thin films can have high potential application in photo catalytic activities.

CuO thin films were deposited onto glass substrates using Chemical bath deposition technique by varying the pH of the solution. Structural, optical and electrical properties of the synthesized films were studied as a function of the solution pH. X-ray diffractometry, scanning electron microscopy, UV-Vis spectroscopy and Hall effect measurements were used to explore the structure, morphology, optical and electrical properties of the films, respectively. All the films have exhibited orthorhombic structure with preferential orientation along the (111) plane. X-ray line profile analysis has been carried out to determine the microstructural parameters such as crystallite size, RMS microstrain, dislocation density and stacking fault probability. Morphological studies have revealed that the uniformity of the film surface, and the average particle size was found to increase with solution pH. Optical parameters such as band gap, refractive index, extinction coefficient, real and imaginary dielectric constants and optical conductivity have been estimated from optical absorption measurements. Carrier concentration and mobility of charge carriers estimated from the Hall measurement were found to be 7.43 9 10 13 cm -3 and 11.84 cm 2 V -1 s -1 respectively for CuO films prepared at solution pH 11.0.

Thin films of cupric telluride (CuTe) of thickness from 50 to 200 nm have been prepared using a thermal evaporation technique onto well‐cleaned glass substrates kept at 300 K under a vacuum better than 2 × 10–5 mbar. After annealing the deposited films at 375 K for an hour, the resistivity of these films and that of bulk CuTe were measured using the four‐probe technique as a function of temperature from 80 to 310 K. It is found that the bulk sample of CuTe exhibits metallic behaviour and the thin films show semiconducting be‐ haviour. Activation energies of the films have been evaluated and are in the range 0.05 and 0.15 eV. The metallic behaviour of bulk CuTe down to 4 K indicates that the variable range hopping mechanism is absent in CuTe at least down to liquid helium temperature. X‐ray diffraction analysis confirmed the composition and polycrystalline nature of the CuTe films. The grain size of CuTe thin films, estimated from atomic force microscopy measurements, is around 40 nm. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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