目前市面上和未來幾年是以PERC技術為主流的太陽電池，而且使用ｐ型單晶矽PERC太陽電池的比例最高。PERC電池背面的鈍化層除了能反射更多光線，更能減少少數載子復合。氧化鋁（Al2O3）有多而穩定的負電荷特性使其非常適合作為ｐ型矽的鈍化材料，以原子層沉積（ALD）系統成長Al2O3可獲得優異的鈍化品質。
　　本研究使用thermal ALD系統以三甲基鋁（TMA）為鋁來源，水為氧來源在矽表面成長的Al2O3已經具備一定程度的化學鈍化，再透過熱退火產生高密度固定負電荷感應電場形成的場效鈍化更是大幅提升鈍化表現。N2 95% + H2 5%的合成氣體退火（FGA）相較於N2退火可以更有效提升鈍化品質，表示其中所含的氫有所貢獻。400 °C可能是退火的臨界溫度，在400 °C以上可縮短退火時間且成效更好。
　　矽表面的預處理會影響Al2O3的鈍化品質，沉積前的清洗作業中保留矽表面的原生氧化層或清洗過程形成的氧化矽，對於Al2O3薄膜後續退火和高溫處理有更好的表現，這可能與Si/ Al2O3介面的SiOx特性有關。

　　Solar cells currently on the market and in the next few years are and will be based on PERC technology as the mainstream, and the largest proportion of PERC based solar cells use p-type monocrystalline silicon. The passivation layer on the back side of the PERC solar cell does not only reflect more sunlight, but it also reduces minority carrier recombination. Aluminium oxide (Al2O3) is very suitable as a passivation material for p-type silicon because of its large and stable negative charge characteristics. The growth of Al2O3 by the atomic layer deposition (ALD) technique provides excellent passivation quality.
　　In this study, the thermal atomic layer deposition system used trimethylaluminum (TMA) as the aluminum source and H2O as the oxygen source to grow Al2O3 on the silicon surface to a certain degree of chemical passivation. After thermal annealing, the field effect passivation formed by the high-density negative fixed charge induced electric field which greatly improved the passivation ability. Compared with N2 annealing, forming gas annealing (FGA) (N2 95% + H2 5%) can improve passivation quality more effectively, indicating that the hydrogen contained therein contributes to the improved passivation quality. 400 °C may be the critical temperature for annealing, above 400 °C can shorten the annealing time and achieve better results.
　　The pretreatment of the silicon surface will affect the passivation quality of Al2O3. In the cleaning process before deposition, the native oxide on the silicon surface or the silicon oxide formed during the cleaning process is retained, which has better performance in the subsequent annealing and high temperature treatment of the Al2O3 film, this may be related to the SiOx characteristics of the Si/Al2O3 interface.

第一章 緒論 1
1.1 前言 1
1.2 研究動機 2
1.3 論文架構 4
第二章 理論基礎 5
2.1 太陽電池 5
2.1.1 工作原理 5
2.1.2 傳統矽晶太陽電池 9
2.1.3 載子的復合 10
2.1.4 表面鈍化 13
2.1.5 C-V特性 14
2.2 原子層沉積 22
2.2.1 背景 22
2.2.2 氧化鋁生長機制 24
第三章 應用原子層沉積於太陽電池之表面鈍化 27
3.1 表面鈍化層製備 27
3.1.1 儀器介紹 27
3.1.2 實驗步驟 33
3.1.3 分析結果 36
3.2 MOS元件製備與分析 41
3.2.1 儀器介紹 41
3.2.2 實驗步驟 44
3.2.3 分析結果 46
第四章 氧化鋁鈍化之特性優化 55
4.1 熱退火參數之優化 55
4.1.1 實驗步驟 55
4.1.2 分析結果 56
4.2 基板清洗流程之優化 59
4.2.1 實驗步驟 59
4.2.2 分析結果 62
第五章 結論與未來方向 65
5.1 結論 65
5.2 未來方向 65
參考文獻 67

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