Growth and properties of sprayed iron disulfide (fes2) thin film

Abstract

Recently, iron pyrite (FeS2) has been considered as a potential material for thin film solar cells and wet cells. Ir- che present work pyrite FeS2 films have been grown by spray pyrolysis followed by sulfidation. The deposition parameters were identified and their optimum values determined. The following values were found: temperature = 500°C, spray rate = 24 cm3/min, and substrate to sprayer nozzle distance 35 to 40 cm. The contents FeC13: CS (NH2) 2 : H20 of the spraying mixture were found to be in the volume ratios 0.07:0.15:0.78 for molarities in the range 0.1 and 1 while for molarities less than 0.1 the volume ratios were 1:2. Transmission data analysis in the wavelength range 0.4 ~m and 0.8~m gave an indirect energy gap = 1.17 eV, a possible direct band gap = 2.60 eV and an absorption coefficient = 104cm·1.Sulfidated samples showed absorption coefficient of =105cm-1 • The structural analysis revealed an improvement in the crystallization with the increasing sulfidation temperature. The films showed a preferred orientation in the (200) direction. Electrical transport properties study indicated that the films exhibit n-type conduction. The carrier concentration was found to be n = (0.15 - 0.23) X1017 cm-3, the Hall mobility ~H = 0.6 to 1.5 cm2V<s-1 and the Hall constant RH = (-4.2 to -2.3)x102 cm3c-1.