近年來，有越來越多人開始投入太陽能電池的研究，因此技術進步的很快，目前研究雖然都有不錯的轉換效率，但由於成本高昂，故一直無法普及，因此找尋新的材料來壓低太陽能電池成本是必需的，然而在各種新材料被研究與開發的情況下，硒化銅錫(Cu2SnSe3)薄膜其具有低成本、材料來源充足且能隙為0.7~0.9 eV等特性，但卻很少研究探討將其應用於薄膜太陽能電池之吸收層上。
本研究以濺鍍法製備Cu2SnSe3薄膜，並探討不同靶材、基板溫度、退火溫度和補償碇等不同變數對Cu2SnSe3薄膜特性之影響，並且透過X-ray繞射分析儀(XRD)、場發射電子掃描式顯微鏡(FE-SEM)和能譜儀(EDS)分析Cu2SnSe3薄膜之物理特性，透過霍爾量測(Hall measurement)與吸收光譜(Absorption spectroscopy)分析薄膜電學及光學特性。
經由實驗結果得知在基板溫度為400℃下濺鍍沉積，接著在500℃下退火熱處理後的Cu2SnSe3薄膜有較佳的結晶特性，其薄膜為多晶結構，晶粒大小約1~3 μm，薄膜為P型半導體，能隙為直接能隙，能隙寬度為0.7~0.8 eV，吸收係數在退火前後均維持在104 cm−1、載子濃度為5×1019 cm-3及載子遷移率為8~10 cm2V-1s-1。

Recently, the research of solar cells is much more attractive and its technological progress is very fast. Although solar cells have reached a good conversion efficiency, high cost has limited their further applications. Lowering the cost with the finding of new materials is necessary. Although there are many CuInSe2 replacements, low-cost Cu2SnSe3 thin films with an energy band gap of 0.7-0.9 eV have not been seriously investigated for the absorption layer of the solar cells.
In this study, the effects of the target composition, substrate temperature, annealing temperature, and the Se compensating discs on the sputtered Cu2SnSe3 thin films are discussed. The physical characteristics of the Cu2SnSe3 thin films were invstigated by XRD, FE-SEM, and EDS XRD. Hall measurement and Absorption spectroscopy were used for the electrical and optical properties, respectively.
The experimental results shows that the sputtered Cu2SnSe3 thin films deposited at 400oC followed by annealing at 500oC have a better performance. At this condition, the films are p-type and have well crystallized with a large grain size of 1-3 m, a direct energy gap of 0.7-0.8 eV, an absorption coefficient of 104 cm-1 before and after annealing, a carrier concentration of 5×1019 cm-3, and the highest carrier mobility of 8~10 cm2V-1s-1.

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