| To cut down price of the solar cells,it is important of increasing the efficiency. Among the ways, increasing the responsing rang of solar spectrum is one of the most effective method.There are two advantages of the SiGe thin film for solar cell application. First, it could increase optical absorption coefficient. The optical absorption coefficient of germanium is one or two orders of magnitude larger than that of microcrystalline. It is expected that SiGe is able to absorb sufficient light with thinner materials. Second, the band gap of SiGe alloy can be tailored to absorb different parts of the solar spectrum. The band gap of the germanium is only 0.66eV and almost could absorb all sun's radiation. So SiGe alloy attract a great deal of research interesting for solar cell application.The microcrystalline silicon-germanium (μc-SiGe:H) thin films used in this study were fabricated by reactive thermal chemical vapor deposition(RT-CVD). Several series of microcrystalline silicon-germanium thin films fabricated under different silane concentrations, reactive pressures, discharge powers and substrate temperatures have been studied. The results indicated that their dark conductivity increased with the decrease of reaction gas concentration and reaction pressure, and the increase of discharge power and substrate temperature. However, the photosensitivity and crystalline volume fraction (Xc) showed the opposite regular. The thin films with high quality were manufactured. The crystalline volume fraction of the samples is more then 60% and the photosensitivity is 1000.Relationship between performances ofμc-SiGe solar cells and materials properties were studied. The Voc decreased with the increase of Xc forμc-SiGe solar cells .μc-SiGe solar cell was fabricated with this material. The structure of thin silicon-germanium film solar cells was glass /SnO2 /p-μc-Si:H /i-μc-SiGe:H /n-μc–Si:H /Al . The conversion efficiency with 4.1% was achieved...
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