Indium tin oxide films have been grown by rf sputtering at various Ar-O2 mixtures, at low substrate temperatures (200 °C), and deposition rates (25 Å/min), followed by post deposition annealing (at 350 °C) in different ambients (O2, N2, and cracked ammonia). Influence of a reactive gas (oxygen) on the sputtering rate of a metallic (indium/tin) alloy target has been investigated. Growth parameters and annealing conditions have been optimized. The films were characterized by electron and x-ray diffraction, scanning electron microscopy, and transmittance as a function of wavelength. The effect of heat treatment in various environments on the structural, electrical, and optical properties has been investigated. Effect of a new annealing ambient, cracked ammonia (reducing atmosphere), on the reactively sputtered oxide films is being reported for the first time. Cracked ammonia was found to be very effective and cheap and resulted in films of high quality (electrical and optical) with good structural properties. Films with low sheet resistances (Rs=30 Ω/⧠ at film thicknesses of 800 Å and Rs=8.5 Ω/⧠ at film thicknesses of 5000 Å) with high visible transmission (∼95%) have been achieved by annealing in cracked ammonia.

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Polypyrrole thin films doped with para-toluene sulphonic acid were prepared by the electrochemical process. High-energy ion beam irradiation of the polymers is an effective technique to enhance the electrical conductivity, structural property and mechanical properties. So polypyrrole and allyl diglycol carbonate (CR-39 (DOP)) films were irradiated by oxygen ions (energy 100 MeV, charge state O+7) with fluence varying from 1 × 1010 to 1 × 1013 ions cm−2. The effects of swift heavy ions (SHI) on the structural, optical and surface properties of polypyrrole (Ppy) and CR-39 (DOP) polymers were studied in this work using x-ray diffraction (XRD), UV–visible spectroscopy and scanning electron microscopy (SEM). XRD patterns of the pristine and irradiated polymer show that the crystallinity improved after the irradiation with SHI. At the low fluence, crystallinity was found to increase but at high fluence, it decreases which could be attributed to cross-linking and degradation mechanism. The UV–visible spectra show a shift in the absorbance edge towards higher wavelength, which can be correlated with the transition involved in the polymer and variation in the band gap using Tauc's expression. The band gap of polypyrrole was found to decrease from 3.4 to 3.0 eV after irradiation. CR-39 (DOP), however, showed a very large change in the band gap from 4.8 to 3.4 eV. The SEM study shows a systematic change in the surface morphology of the polymers with increasing ion fluence.

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