CZTS 具有直接能隙、極高的光吸收係數、無毒、材料含量充沛及優
異的穩定性等優勢，被認為是極具潛力的薄膜太陽能材料。本研究提出
新的電鍍方式製備銅錫鋅(CZT)合金薄膜並優化薄膜特性。
本文提出兩階段電鍍法進行銅鋅錫硫(CZTS)薄膜的沉積，在前半段
的電鍍時間進行定電壓沉積，先在基板上沉積完整的元素層；後半段藉
由脈衝電鍍的高低電壓切換特性，將不均勻的元素層反覆進行氧化和還
原反應，最後使薄膜呈現出平整且緻密的特性。接著進行 550torr 高壓硫
化，並將硫化溫度提升至 550℃，得到尺寸約 1μm 的 CZTS 晶粒，薄膜
均勻且平整，以利後續的元件製程。
CZTS 薄膜太陽能電池的結構為 SLG/Mo/CZTS/CdS/ZnO/ITO/Al，以
兩階段電鍍法製備而成的 CZTS 薄膜，元件效率達到 0.796%。

SUMMARY
In this study, we propose an novel electrodeosition approach to deposit CuZnSn (CZT) films and optimize the quality of CZT films. Cu2ZnSnS4 thin film were deposited by two-step electroplating and annealed under sulfurization at 550℃ for 550 torr. Solar cells with the structure SLG/Mo/CZTS/CdS/ZnO/ITO/Al were fabricated by two-step electroplating. The best cell exhibited the conversion efficiency of 0.796%.

INTRODUCTION
Cu2ZnSnS4(CZTS) are one of the most promising materials for thin-film solar due to their abundant materials, low-cost, non-toxic, suitable direct band-gap energy of 1.45-1.5eV, and high optical absorption coefficients( over 104cm-1).

Electrodeposited approach is known as low-cost, non-vacuum and high throughput. Scragg et al. reported on CZTS solar cell prepared by subsequent electrodeposition of metallic precursors in the order Cu/Sn/Cu/Zn, annealed in an atmosphere containing Sulphur. The resulting film exhibited more uniform and highly large grains, leading to reduce grain boundary and recombination. The best photovoltaic device was 3.2%. Ahmed et al. prepared CZTS by electrodeposition of Cu/Zn/Sn metal stacks, annealed in a Sulfur atmosphere. A marked photovoltaic efficiency was 7.3%.

In this study, we propose a novel electrodeosition approach to deposit CZT films and optimize the quality of CZT films. Cu2ZnSnS4 thin film were deposited by two-step electroplating. Every layer of Films was first deposited by the first step with potentiostat electroplating, which was transferred to deposit by the second step electroplating with voltage pluse electroplate. The goal is to control thickness of films at first step, subsequently, and improve the surface of films.

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