| The non-regenerated energy resources such as coal,petroleum and natural gas,play an important role in our life.However,the limitation of the non-regenerated energy resources and the environmental problem they cause makes people focus on the exploitation and application of new energy sources more and more.Solar cell,a kind of new clean energy source,is in many people's good graces.Cadmium sulfide(CdS) is a n-type semiconductor with a direct band gap of 2.42 eV, which brings on the important application in solar cells as a window layer.Due to easy preparation process and low price,CdS films attract many people in the solar cell research.The thesis mainly includes two parts.First,the preparation of CdS films by CBD method is conducted and the deposition of CdS films in different reaction conditions is also investigated.Second,assembling p-n heterojunction solar cell devices with n-type CdS films and p-type Cu2O,CdTe films and p-type silicon wafers respectively is studied.And the property of the solar cells is also explored.In the first part,CdS films are prepared by CBD method in CdAc2-(NH2)2CS-ammonia system.The deposition speed is studied by altering reaction conditions such as initial concentration of CdAc2 and(NH2)2CS,pH and temperature. The structure and the optical property of CdS film is investigated by XRD,SEM, ultraviolet absorption and so on.The best deposition condition is summarized and the symmetrical,compact and thickness-contr011able CdS films are finally prepared.In the second part,CdS/Cu2O,CdS/CdTe and CdS/p-Si p-n junction films are obtained by CBD method and electrodeposition method.The heterojunction solar cells are assembled and the photoelectric properties are measured,with the photoelectric conversion efficiency of 0.05%,1.137%and 1.38x 10-4%,respectively.Finally,the effect of different thickness of window layers and absorbing layers on the solar cells' property is explored by altering the thickness of CdS Cu20 and CdTe films.
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