| FeS2 (Pyrite) has been considered as a valuble semiconductor for solar energy sonversion and other photoelectrochemical applications since it consists of nontoxic and abundant elements. Because of the band gap of about 0.95eV and the very high light absorption coefficient (α≥5×105 cm-1 for λ≤700 nm), it might be suitable for sensitization solar cells and in the form of ultra thin films. At first, we overviewed functional properties, recent development and preparation techniques of FeS2 thin film based on solar cells material. Then we have systematically described elementary principle and technical equipment of this method. Analysis instruments relating structure, electric and optical properties have also been introduced.The thesis is a summarization concerning research work during my graduate experience. Two kinds of solutions containing iron element and sulfur element respectively are used to deposit thin films on ITO conduct glass. The obtained films are then annealed in S atmosphere. Structural characterization indicated that the final samples are of pure iron pyrite phase with good crystallizability. According to XRD and SEM, We can see that reaction temperature and sulfur pressure provided by some amount of sulfur could produce an impressive effect on controlling the formation of single-phase pyrite crystals. Furthermore, we have discussed the effects of deposit time, current density and deposit weight on structure, thickness and morphology of the pyrite films during the deposition process. and the desirable reaction conditions was also concluded. A simplified mathematics model was established to analyze the crystal growth process.In annealing process the optimal anneal temperature 500 ℃ for formation of a single-phased pyrite can be obtained.
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