臺灣博碩士論文加值系統

本研究分為兩部分；首先以化學蝕刻法達到一次擴散製作選擇性射極結構，比較選擇性與否對短路電流和效率的差異。在製作選擇性射極結構使用的等向性蝕刻液混和了氫氟酸、硝酸、醋酸，比例為1：40：200的稀釋溶液。溶液中放入磁石旋轉使溶液混合均勻，避免影響部分區域蝕刻速率，由於蝕刻時間較長、蝕刻速率須精準控制，加入了大量的醋酸緩衝。
磷摻雜的濃度、深度與持溫溫度、持溫時間相關，摻雜的磷原子濃度從基板表面向內遞減，在刮除表面磷摻雜層時以四點探針量測阻值變化推斷蝕刻量，再利用蝕刻時間調整最佳選擇性射極所需的照光區磷摻雜濃度，使用二次離子質譜儀驗證蝕刻前後的表面濃度差。利用可見-紫外光光譜儀和掃描式電子顯微鏡作量測，比較實驗中蝕刻時間對金字塔結構及反射率的關係。實驗結果顯示，以本研究的蝕刻溶液比例做重摻雜層刮除，蝕刻四分鐘內反射率與參考片相比無明顯變化；蝕刻一分五十秒可有效將表面高濃度磷摻雜層刮除，形成選擇性射極的結構。
第二，沉積氫化非晶矽薄膜五奈米於單晶矽基板背表面，進行鈍化表面懸浮鍵的作用。利用拉曼光譜儀檢測燒結前後晶體結構的變化，再以傅立葉紅外光光譜儀和QSSPC量測模擬電極燒結前後矽氫鍵含量和少數載子生命期，以此判斷氫化非晶矽薄膜在高溫短時間製程後的鈍化效果。本研究之非晶矽層，於800℃持溫二十秒的高溫模擬後，晶體結構仍為非晶，但是在經過800℃持溫二十秒的模擬燒結後矽氫鍵含量明顯減少，而少數載子存活周期也下降，使得鈍化效果略微降低，在開路電壓方面的提升稍受影響。

第一章　序論 1
1.1太陽能電池的發展 1
1.2文獻回顧 5
1.3 研究目的 6
1.4 論文概要 7
第二章 研究理論 8
2.1半導體物理 8
2.1-1材料與結構分類 8
2.1-2半導體能態 8
2.1-3摻雜與PN接面 11
2.1-4異質接面 13
2.1-5載子產生與複合 14
2.2太陽能電池原理 15
2.2-1太陽光譜 15
2.2-2太陽能電池工作原理 17
2.3太陽能電池等效電路 18
2.3-1理想太陽能電池等效電路 18
2.3-2太陽能電池等效電路 19
2.4太陽能電池特性參數 20
2.5太陽能電池效率損失 22
2.5-1光學損失 22
2.5-2電性損失 23
2.6太陽能電池效率改善 25
第三章 研究方法與製程步驟 28
3.1選擇性射極結構(SELECTIVE EMITTER) 28
3.1-1電極區之平坦化 28
3.1-2照光區之重摻雜刮除 28
3.2氫化非晶矽薄膜(HYDROGENATED AMORPHOUS SILICON) 29
3.3製程步驟 31
第四章 數據分析與討論 37
4.1選擇性射極結構數據分析 37
4.1-1表面形貌分析 37
4.1-2磷擴散分析 40
4.1-3電性分析 43
4.2氫化非晶矽薄膜數據分析 47
4.2-1晶體結構分析 47
4.2-2電性分析 48
第五章 結論 53
參考文獻 54

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