本研究欲開發一無氨水化學水浴法製程鍍製硫化鋅薄膜，並將其應用於銅銦鎵硒(CIGS)薄膜太陽能電池緩衝層。實驗中分別利用硫酸鋅與硫代乙醯胺來當前驅物，相較於傳統製程以氨水作為錯合劑，本實驗在不添加氨水的環境下，將前述兩溶液均勻混合後，於持溫下進行水浴沉積硫化鋅薄膜，後續完成窗口層以及電極的鍍製以完成元件；本研究分別藉由製程中三部分的優化來提升元件轉換效率，分別為:鍍製緩衝層於CIGS表面的前處理、化學水浴法反應時間的調控以及鍍製完緩衝層的後處理來探討其對整體元件的影響；第一部份:在鍍製硫化鋅緩衝層前，藉由化學濕式法於室溫下浸泡於硫代乙醯胺溶液中，將CIGS表面硫化，達到清潔與鈍化CIGS表面的效果，並藉由後續硫代乙醯胺溶液濃度的調控，並找到一優化的硫代乙醯胺溶液濃度應用於CIGS元件上，並探討其對整體元件的影響；第二部分: 藉由化學水浴法反應時間的調控，並和氨水製程鍍製的ZnS薄膜做比較，找出最優化的製程時間，後續分別利用SEM、XPS、I-V量測等分析證實: 無氨水製程中薄膜內Zn(OH)2二次相顯著降低，使整個無氨水製程鍍製的ZnS薄膜具有高度潛力應用於CIGS薄膜太陽能電池上，元件端表現可達9.16%的元件轉換效率，且並未有氨水製程light soaking 現象的產生；第三部分: 藉由緩衝層鍍製完的後處理優化元件，分別為大氣退火處理以及氧電漿處理，並探討其各自對元件的影響，最後藉由合併氧電漿處理和大氣退火處理，無氨水製程鍍製ZnS薄膜的元件轉換效率可提升至10.16%，在不需要額外light soaking的狀況下，即可達到和氨水製程light soaking一小時後10.42%近似的元件轉換效率。

In this study, zinc sulfide thin films are prepared by ammonia-free chemical bath deposition that we can find out the useful parameters applying to CuIn1-xGaxSe2 thin film solar cell. Use the zinc sulfate and thioacetamide (TAA) to be the sources of zinc ions and sulfur ions, respectively. In contrast to conventional process, adding ammonia as a complexing agent. Fabrication of ammonia-free also without any complexing agents CBD-ZnS buffer layer for CIGS was attempted.
The total thesis can divide into three parts to optimize the ammonia-free CBD-ZnS buffer layer devices. The first part: A novel chemical approach that applied at room temperature to clean and passivate at the same time surface of CIGSe absorber before buffer layer deposition. By pre-treatment on CIGS surface with TAA acidic solution, oxides can be removed and additional S-containing layer forms, inducing remarkable enhancement in the electrical performances of the CIGS solar cells.
The second part: the deposition times are controlled. we can fabricate an ultrathin also less Zn(OH)2 formation ZnS thin film by ammonia-free CBD process to form a rigid p-n heterojunction ; Also, light soaking is not needed in this process to optimize photovoltaic performance.The X-ray photoelectron spectroscopy (XPS) is used and measured that indicating the ZnS thin films formed by ammonia-free process revealed higher sulfur-to-oxygen ratio than ammonia process one. 30 minutes is choose for the ideal reaction time. The efficiency 9.16% was achieved without light soaking treatment.
The third part: After ammonia-free CBD-ZnS buffer layer deposition, two different kinds of post-treatment are investigated. By post air-annealing, zinc may diffusion into bulk CIGS that result in the formation of buried p-n homo-junction, significantly improved cell performaces from 1.28% to 9.16%. With extra oxygen plasma treatment, higher sulfur-to-oxygen ratio ZnS thin film obtained by ammonia process may be reduced. Further, combined both oxygen plasma treatment with the post air-annealing, devices using ammonia-free CBD-ZnS buffer layer can reach 10.16%, which is almost the same as that of the cells pepared by ammonia process with 60 minutes light soaking treatment. 

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