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The developments in the employment of ITO (In2O3:Sn) nanoparticles, for the preparation of transparent conducting coatings, were discussed. It was found that the redispersable nanoparticles of transparent conducting ITO can be prepared reproducibly and in adquate amounts for industrial applications by a wet chemical processing. Pure coatings of ITO nanoparticles were observed to exhibit insufficient mechanical properties even after sintering at 1000 °C. It was shown that transparent conducting coatings of an ITO nanocomposite with a thickness of up to 1 µm and a sheet resistance of 1 to 2 kù can be obtained on plastic substrates by a fast and flexible Ultraviolet curing process.

Thin films of MoS x have been prepared on silicon substrates by spin coating and thermolysis of 0.5 M solutions of alkyldiammonium tetrathiomolybdates in 1,2-ethanediamine (EDA) and 1,2-propanediamine (12PDA). The films have been heat treated in air at temperatures between 80 and 250°C and under N2 atmosphere at temperatures between 300 and 800°C. X-ray diffraction shows a restricted crystallisation and amorphous residues in both kind of films. EDA-based films exhibit a high tendency to crystallise whereas 12PDA-based films form associated structures with the solvent preventing precursor crystallisation. An insight into the processes occurring in film formation is gained by infrared spectroscopy which indicates a beginning of the decomposition of the 12PDA-based film at temperatures as low as 80°C with incorporation of the diamine solvent. In contrast, the EDA-based films show first signs of a decomposition at 150°C. The decomposition of the intermediate MoS3 in both cases starts between 250 and 300°C. By means of SNMS depth profiles carbon contents up to 21 and 32 atom-% were found in EDA- and 12PDA-based films, respectively. The films show a significant deficit of sulphur which is compensated by the carbon. Near the surface of the coatings a loss of carbon is observed.

Thin films of MoS 2 and amorphous MoS 3 have been prepared on various glass and stainless steel substrates by thermolysis of spin cast solutions of (NH 4 ) 2 MoS 4 in an organic diamine (ethylenediamine and 1,2-diaminopropane). After deposition the resulting single-source precursor film [(H 3 NC n H 2n NH 3 )MoS 4 ] was dried at 250°C in air and subsequently heat treated at temperatures between 300 and 800°C under inert nitrogen (N 2 ) atmosphere yielding films of MoS x (2 ≤ x ≤ 3) with carbon impurities. The resulting films with thicknesses up to 160 nm (800°C) and 250 nm (300°C) are highly homogeneous with a metallic lustre and appear brown in transmission. While the films are amorphous to X-ray diffraction up to temperatures of 400°C, the crystallinity increases for higher temperatures due to the formation of MoS 2 microcrystallites. Furthermore, the composition and the microstructure strongly depend on the used diamine solvent. Both X-ray and electron diffraction reveal a partially preferred orientation of the crystallites with their basal planes parallel to the substrate ( ⊥ c, type II). After heat treatment at 800°C under N 2 the MoS 2 layer stacks consist of three to four layers with a length of 5-8 nm. The optical characterisation of the thin films shows a strong absorption in the visible part of the spectrum characteristic of MoS 2 with an absorption coefficient α 550 of 2 × 10 5 cm 1 . Tribological measurements up to 5000 cycles against steel reveal the highest wear-life with a friction coefficient μ < 0.1 for coatings heat treated at 500°C. The highest capacity for reversible electrochemical Li intercalation of 30 mC/cm 2 was found in amorphous MoS x coatings (400°C heat treatment). A weak electrochromic effect with a change in transmission of ΔT 0.08 around 800 nm was observed after Li intercalation.

SnO 2 : Sb single and multilayer coatings have been prepared by the sol–gel dip and spin coating method, and by spray pyrolysis from various precursor solutions. Subsequently, the films have been heat treated in a convection furnace or by cw CO 2 laser irradiation, respectively. The influence of the different deposition and heating techniques on the electrical and morphological properties of the resulting films has been investigated by van der Pauw/Hall method and high resolution transmission electron microscopy (HRTEM) cross-sectional images. It is shown that the resistivities of the dip and spin coated films are at least one order of magnitude higher compared to those of spray coated films obtained from the same precursor solution. In dip coated multilayer systems an alternating structure of loosely packed and dense layers can be observed leading to a decrease in resistivity with the number of layers. A similar densified surface structure is found in laser treated films together with larger crystallites. It is concluded that the differences in resistivity occurring from the deposition technique and the heating process are linked to structural differences of the coatings whereas the chemical composition of the solution plays a minor role for the electrical properties.

Sol-gel dip-coated films of transparent conducting antimony-doped tin oxide (SnO2 : Sb) have been heat treated with heating rates varying from 0.2 to 4300 K/s using either a furnace or cw CO2 laser irradiation. The final sintering temperature of 540°C was maintained for up to 15 min. The sheet resistance of the coatings decreases with increasing heating rate. A decrease of the sheet resistance with the sintering time at constant temperature can be observed for low heating rates but the final values are higher than those obtained with higher heating rates. It is assumed that the densification of the coatings is determined by a competition between the nucleation at low temperatures and the growth of the crystallites at high temperatures. The microstructure of the coatings has been investigated by high resolution TEM cross-sections, X-ray diffraction, and Rutherford back scattering (RBS) and has been correlated to the resulting electrical properties measured by 4 point technique. Different mechanisms of heating arise with the furnace and the cw CO2 laser.

Transparent electrically conducting SnO 2 :Sb coatings have been prepared by the sol—gel dip-coating process from an ethanolic solution of SnCl 2 (OAc) 2 and SbCl 3 (5 mol%). The room temperature resistivity of the dip-coated films heat treated in a furnace or by laser IR irradiation is systematically greater than that obtained for films made by spray pyrolysis. Solution precursors and stabilisers and above all the deposition technique are the principal factors which influence the film morphology and hence the electrical properties. Single layers heat treated in a furnace are porous and consist of small, spherical shaped crystalline particles aggregated in a loose structure with a thin but denser top layer. A model of multilayers connected electrically in parallel allows us to determine the electrical parameters of the bulk and interface parts of the layers. Sintering by CO 2 laser irradiation increases the particle size and the packing density resulting in a resistivity that is four times less than for the conventionally furnace heat treated samples.