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CuIn 1−x Ga x Se 2 (CIGS) thin films with x = 0, 0.28 and 1 were prepared by the sputtering of Cu, In and Ga in HiPIMS (High Power Impulse Magnetron Sputtering) or DC magnetron and subsequently selenized in an Ar+Se atmosphere. Optical emission spectroscopy (OES) was used to monitor differences in HiPIMS and DC plasma during sputtering of metallic precursors. Thin film characteristics were measured using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, energy-dispersive X-ray spectroscopy (EDX) and other techniques.

The general purpose of the study is to fabricate and improve upon FeS 2 thin films which can be used as the photon absorber layer for a heterojunction or homojunction solar cell. This work deals with the preparation of the pyrite by an unconventional sol-gel approach. Thin pyrite films were prepared by sulfurizing the iron oxide films previously deposited through the sol-gel method using iron (III) chloride as a precursor. The structural, morphological, electronic and optical properties of the deposited films were determined using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy, Auger electron spectroscopy (AES), UV-Vis absorption spectroscopy, Hall effect and profilometry. The effects of annealing and sulfurization temperatures were studied. The work was also devoted to the research of sodium diffusion from the substrate due to the thermal treatment and its affect on the pyrite films functionality.

A low temperature chemical deposition method has been developed to deposit iron/sulfur thin films onto soda lime glass substrates. The chemical bath deposition (CBD) consists of aqueous solution ferrous sulphate, disodium salt of ethylenediaminetetra-acetic acid (Na 2 EDTA), sodium thiosulphate and organic solutions of ethylenediamine and methanol. The experiments were performed at room temperature and under two different conditions. The films were uniform and adhered well to the soda lime glass substrates. The deposited films were additionally processed in a sulfur and nitrogen atmosphere at a variety of different temperatures to form the pyrite phase of FeS 2 . The as-deposited and annealed thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), optical absorption, auger electron spectroscopy (AES), and resistivity. The optimization of the FeS 2 pyrite growth parameters was determined using XRD. Although both methods appeared to form FeS 2 the second method is the preferable one where additional sulfurization at 450 °C for one hour yielded the films with the maximum crystalline order and stoichiometry.