太陽能電池的應用迄今，已超過五十年。近年來，太陽能電池大量運用在陸地的商業用途。因為矽半導體的發展相當成熟，所以多數商業化的太陽能電池仍以結晶矽為主。結晶矽太陽能電池的轉換效率會受到諸如差排、氧、碳與過渡金屬等材料缺陷與雜質的影響。其中，氧是最主要的有害雜質元素之一，在長晶或太陽能電池的製程中，過飽和的氧會在矽晶片中形成熱施主，新施主和氧沉澱等，而這些缺陷會降低矽晶片的少數載子壽命。

鑑別這些會影響材料少數載子壽命的缺陷，是研究結晶矽材料的首要目標。本論文採用選擇性蝕刻結合光學顯微鏡(OM)以及掃瞄式電子顯微鏡(SEM)，研究了結晶矽太陽能電池中的缺陷形態及密度分佈。利用光致電流量測儀(LBIC)、量子效率量測儀(QE)、能量散射光譜儀(EDS)以及電子微探分析儀(EPMA)等儀器，對結晶矽太陽能電池的雜質、缺陷以及少數載子壽命的分佈特性進行系統化的研究。

Solar cells have been used for over five decades. Recently, they were applied to terrestrial systems, and commercial and building applications. Most of the commercial solar cells are made of silicon semiconductor, which is mature technology for years. The efficiency of a crystalline silicon solar cell is limited by a high density of defects and a high concentration of impurities,such as dislocations；carbon；oxygen and transition metals. As one of the main and detrimental impurities, the supersaturation of oxygen may form thermal donors, new donors, precipitates during the crystal growth or the cell fabrication processes that can lower the minority carrier lifetime in the silicon substrate.

The primary objective of material research in crystalline silicon is the identification of the lifetime-limiting defects. In this thesis,the defects in crystalline silicon solar cell are observed by both OM combined with preferential etching and SEM. The properties of impurities and defects in the crystalline silicon solar cell as well as their impacts on the minority carrier lifetime are systematically studied by means of LBIC measurement, QE measurement, EDS and EPMA.

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