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Molybdenum doped indium oxide (IO) thin films were deposited on the Coring F1737 glass substrates at 400 °C by spray pyrolysis technique. The Mo doping was varied between 0 and 4 at.%. The films were characterized by their structural, electrical and optical properties. The films are confirmed to be cubic bixbyite In 2 O 3 with a strongest orientation along (222) for 0.5 at.% Mo, which is shifted to (400) plane when the Mo doping is increased to ≥ 1.2 at. %. The films deposited with 0.5 at.% Mo showed high mobility of ~90 cm 2 /Vs, resistivity of ~6.8 x 10 -4 Ω cm and carrier concentration of ~1.01 × 10 20 cm -1 with > ~73% transmittance in the visible range between 500 and 800 nm. The transmittance is well extended into near infrared region.

Copper oxide thin films were obtained by annealing (temperature ranging between 100 and 450 °C) the metallic Cu films deposited on glass substrates by e-beam evaporation. XRD studies confirmed that the cubic Cu phase of the as-deposited films changes into single cubic Cu 2 O phase and single monoclinic CuO phase, depending on the annealing conditions. The crystallite size is varied between ~ 12 and 31 nm. The lattice parameters of cubic Cu and Cu 2 O phases are estimated to ~3.60 and ~4.26 A, respectively. The films with Cu 2 O phase showed p-type characteristics. The conductivity is decreased linearly with the decreasing temperature (1/T), which has confirmed the semiconductor nature of the deposited films. The calculated activation energy is varied between 0.10 and 0.16 eV The surface microstructure is changed depending on the variation in the annealing temperature. The poor transmittance of the asdeposited films (

Indium molybdenum oxide thin films were deposited using different radio-frequency sputtering units on glass substrates at room temperature from an In 2 O 3 (95 wt.%): Mo (5 wt.%) target. The film thickness ranges between 160 and 275 nm. The chamber volume of Unit-1 was ~2.4 times larger than that of Unit-2. Apart from the chamber volume, a significant difference between the two units was the sputtering pressure. The films were characterized by their structural, morphological, optical, and electrical properties. A strong reflection from (222) plane was obtained for the ~275 nm thick films deposited in Unit-1. The films deposited with

Optical properties of spray deposited antimony (Sb) doped tin oxide (SnO2) thin films, prepared from SnCl2 precursor, have been studied as a function of antimony doping concentration. The doping concentration was varied from 0-4 wt.% of Sb. All the films were deposited on microscope glass slides at the optimized substrate temperature of 400 °C. The films are polycrystalline in nature with tetragonal crystal structure. The doped films are degenerate and n-type conducting. The sheet resistance of tin oxide films was found to decrease from 38.22 Ω/□ for undoped films to 2.17 Ω/□ for antimony doped films. The lowest sheet resistance was achieved for 2 wt.% of Sb doping. To the best of our knowledge, this sheet resistance value is the lowest reported so far, for Sb doped films prepared from SnCl2 precursor. The transmittance and reflectance spectra for the as-deposited films were recorded in the wavelength range of 300 to 2500 nm. The transmittance of the films was observed to increase from 42 % to 55 % (at 800 nm) on initial addition of Sb and then it is decreased for higher level of antimony doping. This paper investigates the variation of optical and electrical properties of the as-deposited films with Sb doping. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The optimization of tungsten trioxide (WO3) nanoparticles produced via hydrothermal synthesis for application in electrochromic (EC) devices is reported. The structure and morphology of the nanoparticles are controlled by changing the acidity of the aqueous solvent added to the sol-gel precursor (peroxopolytungstic acid) during synthesis. Orthorhombic hydrated WO3 nanorods or monoclinic WO3 nanoslabs are obtained when HCl is added, while synthesis only in aqueous medium results in a mixture of both types of polymorphs. Dual-phase thin films are processed by inkjet printing deposition of the nanoparticles in flexible polyethylene terephthalate substrate with indium tin oxide coating (ITO PET) followed by the deposition of the precursor solution. When compared with purely amorphous tungsten oxide films, the dual phase ones present higher optical densities and improved capacity, and cyclability stability. The best results, obtained for orthorhombic hydrated nanoparticles (ortho-WO3·0.33H2O), are due to its high surface area and improved conductivity. Additionally, the ex situ X-ray diffraction (XRD) lithiation studies show evidence of a higher distortion of the monoclinic when compared with the orthorhombic crystallographic structure, which contribute to the inferior EC performance. These results validate the use of inkjet printing deposition with low processing temperatures for EC dual-phase thin films containing optimized nanoparticles which are compatible with low-cost substrates.