本研究主旨是利用濺鍍製程製作銅銦鎵硒(CIGS)太陽能電池。研究中使用CuInGa、CuGa 及In 靶材組合設計前驅物，再將前驅物置入爐管進行硒化，並研究以硒化之CIGS 為吸收層之太陽能電池的特性(Al/AZO/i-ZnO/CdS/CIGS/Mo/soda-lime glass)。我們以單層CuInGa 做為前驅物設計元件，再以改善元件效能為原則，加入CuGa 層和In 層來調整前驅物結構。最後各別探討CuGa 層和In 層對元件特性的影響。
　　我們利用掃描式電子顯微鏡觀察剛硒化後的CIGS吸收層，發現其表面覆蓋大量片狀的Cu2Se二次相，導致嚴重漏電流問題。經過氰化鉀蝕刻5 min後，表面片狀結構消失改善漏電流。而後續延長蝕刻時間，雖然表面型態沒有變化，卻可以更進一步減少漏電流，推測是內部晶界存在的Cu2Se二次相被蝕刻掉的結果。為了達到良好的能隙漸變分佈，我們在單層CuInGa結構元件的上下分別沉積CuGa層，藉由Ga的導入得到高表面能隙及增加內部能隙漸變。結果顯示藉由CuGa層的導入，提高元件開路電壓(Voc)、短路電流(Jsc)及填充因子(FF)，並提高太陽能電池效率。但由於同時增加Cu的含量，導致元件漏電流增加。
　　進一步的實驗採取在前驅物結構底層加入額外的In層來減低Cu的比例，我們發現增加內部In的含量，能有效抑制漏電流。原因之一推測來自於減少內部晶界所產生的Cu2Se二次相。其次，比較變溫Voc量測到的Ea值及EQE測量的Eg值，發現添加In層能改善表面復合的現象因此提高Voc。從XPS我們得知內部元素分佈情況並藉以推導內部能隙漸變分佈，發現In層改善Ga元素的分佈情形，提升載子傳輸增加Jsc及FF。最後太陽能電池具有Voc=0.46(V)，Jsc=32.689(mA/cm2)，FF=0.63，效率達到9.5%。

　　Two–stage method was used to prepared the CIGS-based solar cells.Sputtering was used to fabricate the CIG precursor, where the CuInGa, CuGa,and In targets were used as the targets to deposit the CIG layer. In the second stage, the precursor was selenized in a furnace. The reference CIGS solar cell was composed of Al/AZO/i-ZnO/CdS/CIGS/Mo/soda-lime glass. In order to improve the performance of solar cells, the CuGa and In layers were
introduced into the CIG absorber. Effects of the insertion of the CuGa and In layers were investigated in details.
　　SEM images revealed that the as-deposited CIGS thin film was covered by randomly distributed Cu2Se sheets, leading to a large leakage current. Thus, KCN was used to etch this unwanted phase. Obviously, the Cu2Se sheets were
reduced by KCN etching for 5 min. When the time of etching further increased, the surface morphology unchanged. However, the leakage current decreased with time of etching. It was attributed to the etching of the grain boundaries. In order to increase the gradient of conduction band, CuGa layer was deposited on the top and bottom of the original CIG structure. The surface energy gap and concentration grading of the Ga, increasing the values of the Voc, Jsc, FF, and efficiency of devices. However, the leakage problem still existed.
　　In layer was introduced to decease the content of Cu. The leakage current was effectively suppressed when In concentration increased. One of the possible reasons was that the Cu2Se presented in the grain boundaries was IV
removed. Secondly, temperature–dependent current-voltage measurement was used to investigate the surface recombination energy (Ea). It was found that the addition of In layer suppressed the leakage and raised up the Voc. In
addition, the bandgap gradient of the CIGS bulk increased, promoting the collection of photogenerated carriers. Consequently, the Jsc and FF increased. Finally, the CIGS solar cell with Voc=0.46(V), Jsc=32.689(mA/cm2), FF=0.63
and efficiency 9.5% was achieved.

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