الفهرس 
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Abstract
CdO thin films are deposited on microscope glass slices by spray pyrolysis at substrate temperatures ranging from 350°C to 450°C and spray time ranging from 5 to 30 min for determining the optimum conditions of CdO thin film preparation.The effect of substrate temperature and spray time on structural, electrical and optical properties is studied. XRD studies show that, the prepared films are cubic polycrystalline structure with preferred orientation along (111) and (200) planes. CdO thin films have transmittance greater than 70% in the visible region of the solar spectrum. Undoped CdO thin films which are prepared at 425°C and 25 min have the best structural, electrical and optical properties so that, 425°C and 25 min are the optimum deposition conditions. The Al doped CdO thin films are prepared at concentrations (1%, 2%, 3%, 4%, 5%) while the F doped CdO thin films are prepared at concentrations (2%, 4%, 6%, 8%, 10%). By studying the characteristics of undoped and doped CdO films, it is found that the undoped CdO film which is deposited at 425°C and 25 min has the best structural, optical and electrical properties so it is used for realization the solar cell. Realization of CdO/SiO2/P-Si solar cells have been achieved by spray deposition of CdO as a wide band gap semiconductor, 2.46 eV (window) on an P-type silicon with smaller band gap, 1.12 eV (absorber). A native interfacial layer of SiO2 is grown on the surface of silicon substrate by heating it at 425°C with different time (2, 5 and 10 min.) for formation different thickness of the insulating layer. After that, silver is evaporated through a metal mask to form a metal grid as a front contact, and aluminium is evaporated over the entire back surface of Si layer to form the back contact. Systematic control of the interfacial layer SiO2 thickness improves the performance of the realized CdO/SiO2/P-Si solar cells. It is found that the highest value of efficiency is obtained at 5 minutes oxidation time. The best output parameters obtained for CdO /SiO2/P-Si cells are; open circuit voltage VOC = 406 mV, short circuit current density JSC =12.6 mA/ cm2, fill factor FF =0.60 and efficiency =3.06%.