業界太陽能電池效率已到瓶頸，所以現今許多學者著重於成本的降低，因此本論文的主題是開發一種化學濕法沉積方法，用於形成表面鈍化薄膜，以取代業內使用的傳統真空沉積設備。首先由實驗室的特殊製絨，將n型單晶片表面形成微結構，並降低其反射率，接著使用實驗室內的爐管擴散，再利用四點探針找出擴散成功的片子，發現其lifetime比未擴散時提升，從此證明有好的擴散效果。由於粗糙化時蝕刻較深，所以需要探討最佳抗反射層厚度，發現在160nm時，其反射率對波長的分布圖最為恰當。

另一部份則是如何產生效果最好的鈍化層，用單晶空片直接在其雙面塗上氯化鋁，並探討不同退火溫度、不同退火時間和不同氯化鋁濃度的lifetime變化，而發現在退火時間25秒、退火溫度為820℃和1g氯化鋁/100ml水 時會有最高lifetime提升的倍率(9.29倍)，因此鈍化層都用這參數。

而最後的I-V量測效率，因為製絨粗糙化的關係，所以需要更長的燒結時間，才能使正面銀漿穿過氮化矽抗反射層，而實測結果在燒結40秒會有最好的效率，全面鋁效率最高為9.97%，而PERC架構效率只有約6.5%，用SEM觀測其背部BSF的厚度， 發現全面鋁的厚度不一，而PERC架構厚度很薄甚至沒有，原因可能是背部沒拋光導致背部的溶液和漿料都不均勻，影響其接觸的效果，因此未來會想辦法研究出背部平坦化的技術，提升更好的效率。

The solar energy efficiency has lately been stranded at a bottleneck of development, and therefore the only thing that many researchers pay attention to is to lower the cost. Thus, the main theme of this thesis is developing a chemical wet deposition method for forming surface passivation thin films to replace conventional vacumn deposition facilities used in the industry. First, we textured the n-type wafers such that microstructures were formed on their surfaces,in order to reduce the reflectivity after an antirefiection layer was later coated the surface. To form a dopant layer on the front, we used the horizontal tube to diffuse phosphorus into the wafer. Then, the successfully diffused wafers were confirmed by 4-point probe measurement. Because the textured wafers were etched a little deeply, we had to chooce a proper thickness of the antirefiection layer ,which was 160nm in this study.

Another part of this study is about how to generate the best passivation layer by coating AlCl3 on both side of the monocrystalline wafers. We discuss the lifetime variation with different annealing temperature , annealing time , as well as the concentration of the AlCl3 soultion. We found the best condition for forming the passivation layers, which is 25sec for the annealing time, 820℃for the annealing temperature, and 1g /100ml for the solution concentration. These parameters were utilized thoughout this study.

The textured wafers needed more sinter time to make the silver paste go through the antireflection layer of SiNx because the SiNx layer was thick. The best sinter time was found to be 40 seconds. In our study, the cell with full aluminum rear contact had a conversion efficiency of 9.97%, in contrast to the 6.5% of PERC cells fabricated by sintering a gird pattern of aluminum rear contact. The reason for the low efficiency of PERC cells was the lack of uniform back surface fields over the rear surface.

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