近些年為了提升矽晶太陽能電池的效率，以PERC(Passivated Emitter and Rear Cell)架構的太陽能電池成為主流。製作PERC太陽能電池的製程中，背表面鈍化是必要的步驟。
本實驗利用p型矽基板製作太陽能電池。首先我們在商業藍片(在已經過磷擴散製程的p-n片正面，沉積氮化矽抗反射層之晶片)背面，使用電子束蒸鍍機蒸鍍一層鋁金屬薄膜，並以高溫爐管對其進行氧化，再將樣品放入燒結爐中進行退火，並且使用WCT-120對樣品進行少數載子壽命的測量，找出最佳的製程條件為:鋁薄膜厚度3nm，氧化溫度400℃，時間10分鐘，和退火溫度700℃，時間3分鐘。待氧化鋁鈍化層製備完成後，我們在背面的鈍化層上沉積一層氮化矽薄膜，並進行二次退火，退火條件為溫度400℃時間，時間為10分鐘。
藉由XPS量測可以得到氧化鋁薄膜之元素組成，並以TEM量測氧化鋁之厚度，即可使用C-V量測其負電荷密度。最後使用最佳製程參數製作出PERC太陽能電池，並達到填充因子為75%，轉換效率達到17.13%。

In recent years, to promote the efficiency of solar cells, PERC (Passivated Emitter and Rear Cell) structure solar cells have been widely used. To fabricate a PERC cell, a passivation layer, usually an AlO_x layer, is deposited on the back surface of the solar wafer.
In this experiment, we used p-type silicon substrates to manufacture solar cells. First, we deposited an aluminum film on the back surface of a blue wafer, i.e., a semi-finished solar cell with SiN_x anti-reflection coating (ARC) layer deposited, by an E-beam evaporator. The blue wafer is a textured substrate which is phosphorus diffused and deposited with a SiN_x ARC on its front surface. Then, the as-deposited sample was put into a furnace which is full of oxygen for oxidation. After that, it was annealed in a sintering furnace. In the end, the sample was measured by WCT-120 equipment for us to know its minority carrier lifetime. Through a series of measurements, we then found the best conditions, and they are 3nm aluminum film thickness, an oxidation process lasting for 10 minutes at 400℃, and an annealing lasting for 3 minutes at 700℃. After the completion of the passivation layer, we stacked a SiN_x film on the back surface to protect the passivation layer. And then, we put it into sintering furnace to do the second annealing process. The best annealing temperature and annealing time are 400℃ and 10 minutes, respectively.
By using XPS (X-ray photoelectron spectroscopy) measurement, we then obtained the aluminum oxide film element composition. Also, we used TEM (Transmission electron microscope) to measure the thickness of the aluminum oxide formed. And then, we calculated the negative charge density of the passivation layer. Finally, PERC solar cells were fabricated using the best parameters, and a best conversion efficiency of 17.13% was achieved with a fill factor of 75%, short-circuit current density of 38.71〖mA/cm〗^2 and open-circuit voltage of 0.59V. These PERC cells were then compared with all-back-surface-field cells fabricated at the same time, following a standard cell fabrication process. A substantial improvement in conversion efficiency can be found from the comparison.

致謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VI
表目錄 X
第一章、導論 1
1.1 前言 1
1.2 文獻回顧 1
1.2.1 太陽能電池發展及分類 1
1.2.2 PERC太陽能電池(Passivated emitter and rear cell) 3
1.2.3 鈍化層之發展及選擇 6
1.2.4 氧化鋁鈍化層之製備 7
1.2.5 鈍化層之負電荷密度與少數載子壽命之影響 8
1.3 研究目的與動機 9
1.4 論文架構 10
第二章、太陽能電池基本原理 11
2.1 太陽能電池基本工作原理 11
2.2 太陽能電池等效電路 12
2.3 太陽能電池之重要參數 14
2.4 背表面場效應(Back Surface Field，BSF) 17
2.5 氧化鋁之場效鈍化 18
2.5 C-V量測原理 18
第三章、研究方法與製程步驟 22
3.1 實驗架構 22
3.2 實驗流程圖 23
3.3 實驗步驟 24
3.3.1 清洗程序(Wafer Clean) 24
3.3.2 表面粗糙化(Texturing) 24
3.3.3 磷擴散(Phosphorous Diffusion) 25
3.3.4 磷玻璃去除(PSG removal) 25
3.3.5 晶邊絕緣(Edge Isolation) 25
3.3.6 蒸鍍鋁(E-gun Al) 26
3.3.7 爐管氧化(Furnace oxidation) 26
3.3.8 退火(Annealing) 26
3.3.9 背面氮化矽層沉積(SiNx deposition) 26
3.3.10 黃光製程(Photo Lithography) 27
3.3.11 網印電極(Screen Printing) 29
3.3.12 共燒結(Co-firing) 29
3.4 儀器介紹 30
第四章、實驗數據分析 39
4.1 爐管氧化金屬鋁形成氧化鋁薄膜之少數載子壽命 39
4.1.1 蒸鍍不同厚度鋁對少數載子壽命的影響 39
4.1.2 不同氧化溫度及氧化時間的影響 41
4.1.3 退火溫度及時間對少數載子之影響 45
4.2 背面保護層氮化矽之研究 48
4.2.1 少數載子壽命之衰減 48
4.2.2 背面氮化矽二次退火之研究 49
4.3 XPS元素組成分析 52
4.4 TEM量測 54
4.5 固定負電荷量測 57
4.6 SEM量測 60
4.7 元件轉換效率量測 62
4.8 Suns-Voc量測 65
4.9量子效率量測 66
第五章、結論及未來展望 68
參考文獻 70
附錄 75

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