本論文研究目的是利用實驗室分子束儀器(MBE)在N型摻雜砷化鎵(GaAs)基板成長耦合量子點(InGaAs)磊晶層，而量子點層間分別由5、10與15奈米的砷化鎵做為分隔層，使量子點間產生耦合作用，並期望能實現由Luque 與 Marti提出的中間能隙理論。
量測方面，我們使用實驗室的量測系統:電激螢光、光電流、電制吸收以及電調制反射光譜(electro reflectance)對樣品進行比對分析，並在AM1.5G作檢視，以獲得太陽電池基本參數。
太陽電池量測結果發現，量子點結構有助於長波長光子的吸收，可提升光電流的收集，然而，量子點層會產生應力，使得開路電壓的嚴重衰減，而影響轉換效率，使得轉換效率無法高於baseline。轉換效率的表現上，九層耦合量子點結構c494(5nm)、c519(10nm)與c520(15nm)為4.3%、5.1%與5.3％，九層耦合量子點綴於量子井結構c524(5nm)、c525(10nm)與c526(15nm)為3.9%、4.2%與4.7％，十、十二層耦合量子點結構c514(5nm)、c538(10nm)與c529(15nm)為2.9%、4.48%與5.89％。由數據分析可得知，間隔層厚度會影響轉換效率，厚度增加有助於應力的釋放，可降低缺陷的產生，使得轉換效率提升。
本論文之突破是在於樣品c529（VOC =0.64V, JSC =11.97mA/cm2,FF=67%,η=5.89%）的轉換效率可成功高於GaAs （VOC =0.87 V, JSC =7.4 mA/cm2,FF=72.3%,η=5.6%），由於樣品的量子點磊晶品質佳，幫助電流值大幅增加，足以彌補VOC與FF的衰減，因此有效的提升整體轉換效率且突破baseline。

The purpose of our research is growing the coupled InGaAs quantum dots on the n-type substrate by molecular beam epitaxy in laboratory, and we choose 5,10 and 15 nanometers to be the thicknesses of GaAs spacer between the quantum dots layer. Due to the couple effect, we hope to realize the theorem of intermediate band proved by Luque and Marti. We measure the characteristic of samples by electroluminescence spectra, photoelectric current spectra, electrical absorption spectra and electro reflectance spectra in laboratory; moreover, we acquire the basic parameters of solar cell by AM1.5G for analyzing.
From the basic parameters of solar cell, we know that the quantum dots can enhance the photocurrent by absorbing additional photons , however, the strain caused by quantum dots would decay the open voltage seriously, so that the efficiency always under the baseline. Each efficiency of 9-stack QDs are 4.3%(c494),5.1%(c519),5.3% (c520),and each efficiency of 9-stack Dwells are 3.9%(c524),4.2%(c525),4.7%(c526), and 10-stack QDs(5nm) is 2.9%(c514),and 12-stack QDs(10nm) is 4.48%(c538),and 12-stack QDs(15nm) is 5.89%.
The break through of this paper is that the efficiency of c529（VOC=0.64V,JSC=11.97mA/cm2,FF=67%,η=5.89%）is higher than GaAs（VOC =0.87 V, JSC =7.4 mA/cm2,FF=72.3%,η=5.6%）,and we attribute this performance to its good quality of miniband, because the current can be enhanced a lot, and it will make up for the lose of open voltage and filling factor, so that the efficiency can be higher than GaAs baseline.

論文審定書 i
誌謝 iii
中文摘要 v
英文摘要 vi
第一章 緒論 1
1-1 前言 1
1-2 Ⅲ-Ⅴ族太陽電池 1
1-3 中間能隙（intermediate band）架構與基本原則 3
1-4 實驗動機 4
第二章 實驗樣品介紹 6
2-1 耦合量子點太陽電池結構 6
第三章 實驗方法與製程步驟 12
3-1 光激螢光量測 12
3-2 電調制反射光譜量測 13
3-3 電激螢光量測 14
3-4 光電流量測 15
3-5 電致吸收量測 17
3-6 量測元件mesa製程步驟 18
第四章 實驗結果與分析 23
4-1 螢光光譜比較與分析 24
4-2 吸收光譜比較與分析 44
4-3 電調致反射光譜比較與分析 57
4-4 外部量子效率（EQE）分析 70
4-5 I-V量測 72

第五章 結論 80
參考文獻 82

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