本論文針對三五族化合物半導體氮化銦鎵(InGaN)系列太陽能電池元件製作與分析。傳統氮化鎵光電元件由於成長在絕緣的藍寶石基板上，使得元件正負電極須製作於同一平面；然而氮化銦鎵材料缺陷密度高達 108 ~1012 cm-2，光載子傳輸時容易被材料缺陷所捕捉進而影響元件操作特性。本論文利用晶圓鍵結(wafer bonding)方式將氮化銦鎵磊晶層從絕緣的藍寶石轉置到高導電率的矽基板而形成垂直式載子傳輸方向之電極結構。光載子在空乏區分離後傳輸至電極的路徑大幅縮短，使得載子傳輸時被材料缺陷所捕捉的數量因而降低，故可有效提升光電流。垂直式電極結構相較於傳統水平結構有較佳的元件操作表現，其光電流提升76 %。垂直結構之太陽能電池各項參數JSC、VOC、FF以及 η 分別為1.32 mA/cm2、2.38 V、71.4 %以及2.24 %。此外，本論文於電池元件磊晶層中額外置入AlGaN與n-InGaN結構，並探討串聯電阻對於太陽能電池之特性研究。

In this study we focused on fabricating and analyzing the InGaN-based photovoltaic (PV) devices. Conventionally, electrodes of GaN-based optoelectrical devices were fabricated laterally on the same side due to non-conducting sapphire substrates, which were much different from conducting Si or GaAs substrates. Because of the high threading dislocation density of InGaN/sapphire materials (about 108 ~ 1012 cm-2), photocarriers could be easily captured by trap states. In our work, the InGaN epitaxy was transferred via wafer bonding techniques from sapphire to Si substrates. The transit distance of photocarriers separated from the depletion region to the external circuit could be greatly shortened. The photocarriers captured by trap states could be decreased and hence the increased photocurrent. Compared with the conventionally lateral-type fabrication, devices in vertical-type electrodes exhibited better solar cell performance with enhanced JSC, VOC, FF and η of 1.32 mA/cm2, 2.38 V, 71.4 % and 2.24 %, respectively. In addition, the InGaN PV devices with another AlGaN or n-InGaN insertion layers were also studied. Band diagram simulation showed that 2-dimentional electron gas (2DEG) could be formed to lower down series resistance so that enhanced the power conversion efficiency of InGaN PV cells.

第一章 序論

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第二章 原理

【1】J. Nelson, “The Physics of Solar Cell,” Imperial College Press, London, 2003.
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第三章 實驗製程步驟

【1】 W. S. Wong, N. W. Cheung and M. Kneissl, “Fabrication of thin-film InGaN light-emitting diode membranes by laser lift-off,” Appl. Phys. Lett., vol. 75, no. 10, pp. 1360-1362, 1999.
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第四章 實驗結果與分析討論

【1】 S. Chichibu, T. Azuhata, T. Sota and S. Nakamura, “Spontaneous emission of localized excitons in InGaN single and multiquantum well structures,” Appl. Phys. Lett., vol. 69, no. 27, pp. 4188-4190, 1996.
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第五章 結論與未來規劃

【1】 M. K. Lee, C. L. Ho, and P. C. Chen, “Light Extraction Efficiency Enhancement of GaN Blue LED by Liquid-Phase-Deposited ZnO Rods,” IEEE Photonics Technology Letters, vol. 20, No. 4, 2008.
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【3】 W. I. Park, G. C. Yi and J. W. Kim, “Schottky nanocontacts on ZnO nanorod arrays,” Appl. Phys. Lett., vol. 82, no. 24, pp. 3358-3360, 2003.
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