الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Thin films of copper tin sulfide Cu2SnS3 (CTS) were successfully deposited by spray pyrolysis technique, in a single step process, using aqueous solutions containing copper acetate monohydrate (C4H6CuO4.H2O), tin chloride pentahydrate (SnCl2.5H2O) and thiourea (SC(NH2)2) as precursors of copper, tin and sulfur, respectively. The effect of deposition temperature and time on structural, morphological, optical and electrical characteristics were investigated. The films were deposited at different temperatures ranged from 250 to 450 ᵒC, and different times ranged from 10 to 40 minutes for each temperature. The films were characterized by means of Xray diffraction (XRD), scanning electron microscopy (SEM), UV—VIS—NIR spectrophotometer and I-V measurments. The X-ray diffraction patterns of the samples proved the polycrystalline nature and the formation of pure tetragonal Cu2SnS3 structure with (112) preferential orientation. The average crystallite sizes calculated using the Scherrer formula ranged from 3 to 9 nm. The SEM images revealed that the CTS films have continuous and dense morphology. The energy band gap varied from 1.29 to 1.58 eV with different preparation conditions and the absorption coefficient (α) was found to be in the order of 3x104 cm-1 . This makes the material a promising candidate for low cost and friendly environment thin film solar cells. The type of conductivity of all prepared samples was P-type. The sheet resistance of spray deposited CTS thin films was affected slightly by that deposition temperature and time. The obtained values of films sheet resistance are suitable for material showing semiconducting behavior. The I-V characteristics of CTS/FTO junction confirmed the formation of ohmic contacts, and demonstrated the possibility of space charge with limited conduction.