無毒害且較低成本之銅鋅錫硫 Cu2ZnSnS4薄膜太陽電池，成為最具潛力取代CIGS薄膜太陽電池的材料。由於電鍍法製程簡單、不須真空設備及低成本等優點，所以本研究採用電鍍成長前導層(Zn/Sn/Cu/Mo與ZnS/Zn/Sn/Cu/Mo)，再將前導層置於高溫爐管中以硫化氫氣氛於550℃進行硫化處理1.5小時。銅、錫、鋅以二極式電鍍系統以定電流法，而硫化鋅為化合物，使用三極式電鍍系統以定電位(壓)法。電鍍硫化鋅層時會改變其電解液配方、脈衝頻率以及總電鍍硫化鋅時間。電鍍硫化鋅層的目的是提高膜的品質，亦即提高膜的晶粒大小及平整度，預期得到與電子束蒸鍍法相同的結果。
SEM分析、TEM分析與GIXRD分析對前驅物進行表面形貌分析、微結構量測、以及結晶結構量測以及研究其硫化後Cu2ZnSnS4薄膜之SEM觀察薄膜表面型態及橫截面影像、TEM分析來檢視薄膜的微結構、拉曼光譜儀來分析薄膜的結構、UV/VIS/NIR光譜儀來分析薄膜的光學性質以及GIXRD來分析薄膜的結晶結構。
將ZnS/Zn/Sn/Cu/Mo前驅物硫化後，所得Cu2ZnSnS4薄膜之表面形貌平整度較佳且晶粒尺寸較大，相較於Zn/Sn/Cu/Mo前驅物硫化後所得Cu2ZnSnS4薄膜。由Raman分析知道硫化後所得薄膜並非純Cu2ZnSnS4，還包含Cu2SnS3、Cu¬3SnS4、SnS化合物。在準備前驅物時，將電鍍硫化鋅時間拉長，則將其硫化後所得之薄膜其Cu2ZnSnS4百分比增加，故其吸收係數增加。故得証在製備前驅物時，除了元素層(銅、錫、鋅)，另外增加一層硫化鋅(ZnS)有助於硫化時Cu2ZnSnS4之形成。
 

Cu2ZnSnS4 (CZTS) thin film solar cell is a low cost, environmental harmless solar cell. In this study, various precursor films containing Cu, Zn, Sn, and S were first obtained by the electrodeposition of Cu , Sn, Zn, and ZnS in sequence on Mo-coated glass substrates. For electrodeposition of Cu, Sn, and Zn, these three processes are under 2-electrode system and we have deposited ZnS on Zn/Sn/Cu/Mo by 3-electrode electrochemical depositon during preparing precursor films. The deposition of ZnS was aimed to enhance the film quality, anticipating to receive the same advantage, i.e., improved surface morphologies and grain sizes, as the precursor films obtained using electron-beam evaporation. After sulfurizing the precursor film of ZnS/Zn/Sn/Cu/Mo, we get larger grains, higher absorption coefficients, and smoother morphologies of Cu2ZnSnS4 than the sulfurized Zn/Sn/Cu/Mo. From Raman fitting results, the sulfurized films is not pure CZTS. It has other compounds, such as Cu2SnS3,Cu¬3SnS4, and SnS. As the total depositing ZnS time increases when preparing the precursor, the Cu2SnS3% decreases which means that Cu2SnS3 reacts much more with the ZnS to form Cu2ZnSnS4. This is proved by the increasing Cu2ZnSnS4 % of the sulfurized thin films : NO, E99-10, E99-20, E99-30 and E99-40. As a result, it is proved that adding one more layer of ZnS during preparation of precursor films helps the formation of CZTS during sulfurization.

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