The effect of doping spray pyrolyzed thin films of In2S3 with silver is discussed. It was observed that silver diffused into In2S3 films in as deposited condition itself. Depth profile using x-ray photoelectron spectroscopy clearly showed diffusion of silver into In2S3 layer without any annealing. X-ray analysis revealed significant enhancement in crystallinity and grain size up to an optimum percentage of doping concentration. This optimum value showed dependence on thickness and atomic ratio of indium and sulfur in the film. Band gap decreased up to the optimum value of doping and thereafter it increased. Electrical studies showed a drastic decrease in resistivity from 1.2×103to0.06Ωcm due to doping. A sample having optimum doping was found to be more photosensitive and low resistive when compared with a pristine sample. Improvement in crystallinity, conductivity, and photosensitivity due to doping of spray pyrolyzed In2S3 films with Ag helped to attain efficiency of 9.5% for Ag∕In2S3∕CuInS2∕ITO (indium tin oxide) solar cell.

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This paper reviews research works carried out on silicon quantum dots (Si-QDs) embedded in the silicon nitride (SiN x ) dielectric matrix films with different fabrication techniques and different characteristics. The advantages of SiN x as a dielectric compared to silicon dioxide (SiO 2 ) for SiQDs from a device point of view are discussed. Various fabrication techniques along with different optimized deposition conditions are summarized. The typical results of structural characteristics of the films with Raman spectroscopy and Transmission Electron Microscopy (TEM) are discussed. The origin of photoluminescence (PL) from the films and the chemical compositional analysis such as X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Secondary Ion Mass Spectroscopy (SIMS) analysis of the films are also made available in brief. The charge conduction mechanism in the films with metal-insulator-semiconductor (MIS) structure, with their electrical characterization like capacitance-voltage (C-V ) and current-voltage (I-V ) measurements are presented.

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