Cu2ZnSn(S,Se)4是極具發展潛力的吸收層材料，與現在的CdTe或Cu(In,Ga)(S,Se)2相比，由於鎘為重金屬環境對人體有害，銦含量稀少且昂貴。因此研究選用地殼含量豐富，價格低且對環境友善的鋅與錫來取代。
研究使用DMSO為溶劑來配置銅鋅錫硫硒(CZTSSe)溶液，藉由旋轉塗佈法製備薄膜，探討硒化後再硫化對於薄膜的影響。利用掃描電子顯微鏡(SEM)、能量色散X射線光譜(EDS)分析硒化後硫化薄膜與成分比例之變化、X-射線繞射分析(XRD)與拉曼光譜(Raman)確認CZTSSe薄膜之晶體結構，將薄膜製作為元件並透過I-V量測了解其光電特性。
將前驅物以不同的升溫速率以及持溫時間上升至500度進行硒化退火，發現以每分鐘10度的升溫速率，有較好的結晶性質，其表面緻密度較高。為了將CZTSSe表層硫化以達到提升開路電壓的目的，我們將硒化後CZTSSe薄膜放入高壓伏中進行硫化，經由EDS以及XRD分析，我們發現經過高壓後硫化中硒的成分將被硫以不同比例所取代，因此可以藉由控制壓力以及溫度來調整硫與硒之間的比例並且進一步達到控制薄膜的能帶的目的。
XRD分析顯示，在硫化前有CuSe二次相產生，與拉曼光譜檢測到的二次相吻合，但CZTSSe經高壓後硫化熱處理，表面沒有二次相產生。
我們將ZnO的製程時間縮短，使得穿透率提升，之後使用ITO取代AZO，讓元件串聯電阻值下降，而緩衝層的部分，我們加入了磁石以及溫度探棒，更嚴謹的控管製程方式，由結果顯示，改善後段製程與材料，從原本效率0.87 %上升到2.34 %。

CZTSSe is a promising material for thin film solar cells, which consists of earth-abundant, low-cost and environmentally friendly material compared to CIGS or CdTe. CZTSSe thin films were fabricated using DMSO-based spin coating technique. In this work, we investigate the effects of sulfurization for the selenized CZTSSe thin film. EDS and SEM were performed to analyze the change of composition and morphology of films. XRD and Raman were used to confirm the crystal structure of CZTSSe thin films. CZTSSe-based devices were measured through I-V measurement in order to investigate the photoelectric property.
The effects of the heating rate and holding time during the selenization process on the properties of CZTSSe thin film were investigated. It is found that the crystalline quality and morphology of the CZTSSe absorber can be improved by using a heating rate of 10 °C/min. The result shows that the CuSe secondary phase is formed before sulfurization, which is consistent with the obtained secondary phase detected by Raman spectroscopy. After high-pressure post-sulfurization heat treatment of CZTSSe, there is no secondary phase on the surface.
The transmittance of ZnO is shorted by reducing the process time, and the AZO was replaced by ITO to reduce the series resistance of the device. To optimize the buffer layer, magnets and temperature probes were used in the solution to control the stability of process. The device efficiency was increased from 0.87 % to 2.34 % based on the proposed process.

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