有鑑於能源的短缺，石油的耗竭。如何研發新一代的替代能源十足的重要，太陽能的出現展現了新的契機，太陽每天放出光和熱，如何有效的利用其能量轉換成人類常用的能源很值得人們去開發與研究。
現今太陽能電池尤以三五族化合物半導體的太陽能電池效率最高。三五族太陽能電池主要是因為有較高的轉換效率以及其能隙調變，將其互相串接結合的無限發展性，以及優越的抗輻射能力，使得三五族太陽能電池不論是應用在的表的日常生活抑或是在外太空的酬載都有很大的發展性。有鑑於此我們利用有機金屬化學氣相沉積法成長較簡易之三五族單接面砷化鎵太陽能結構，以此為太陽能電池之基本結構基底，在太陽能電池表面製備一層抗反射層以增加入射光吸收率，進而使得電子電洞對增加以增加光電流，而使太陽能電池效率提升。
在本論文中探討薄膜型抗反射層以及微結構與奈米結構之抗反射層應用在太陽能電池上之效應，以增加其光電流於砷化鎵太陽能電池上面以提升效率。首先使用MATLAB 軟體理論計算出最適當的薄膜厚度與折射率條件再使用溶膠凝膠法製備薄膜型抗反射層實際應用在太陽能電池上使用ZnO 以及 MgF2兩種材質能將反射率降低10%而效率提升30%。接著探討微結構上使用壓印技術製備各種不同模具圖形壓印出各種不同圖形的結構型抗反射層於砷化鎵太陽能電池上面探討其效應。結果發現三角柱狀的微米壓印在EPOXY於砷化鎵太陽能電池上面能降低反射率至11% 並且提升效率約為28%。
最後使用水溶液法成長奈米等級之氧化鋅奈米線之抗反射層於太陽能電池結構上面並探討其效應。其中抗反射能力能將反射率降低至10 %同時提升效率至42%。比較三種不同之抗反射層於砷化鎵太陽能電池效率提升之多寡，使其將來可應用在多種太陽能電池上面。
使用表面抗反射層能輕易的增加太陽能電池之效率，使太陽能電池在生活上的實用價值顯著提升，有助於拓展太陽能電池的應用領域與普及率。

Because of the energy shortage and the oil crisis are getting more and more serious. How to find renewable energy to replace the oil is an important issue for our live! The solar power is a turning point of the new sources of energy. Sun generate light and heat every day. It is worth to research how to convert the solar energy to electricity to satisfy our demand..
The highest conversion efficiency in different kind of solar cells can be found in the III-V compound solar cell. The advantages of the III-V solar cell are high absorption coefficient, high conversion efficiency, high radiation resistance, broad spectral response and concentrator system integratable. This tandem structure can be used in III-V compound solar cells to utilize the entire solar spectrum, and the radiation resistance makes it suitable for space application. We use Metal-organic Chemical Vapor Deposition (MOCVD) method to grow the simplest structure single junction GaAs solar cell and add antireflection coating layers on the devices to enhance the light transmission. The enhancement of light transmission helps to generate more electron-hole pairs. Therefore both of the current density and the efficiency of solar cells can be increased.
The effect of thin film and textured antireflection coating on GaAs solar cells to enhance the conversion efficiency will be investigated in this thesis. We use MATLAB software simulation to find out the best combination of refractive index and thickness of the thin film antireflection coating layer and utilize the sol-gel method to prepare the thin film with ZnO and MgF2 on the GaAs solar cells, which can help to reduce the reflectivity to 10%. And the conversion efficiency can be improved for about 30%. Next we discuss various textured surface with micro-scale pattern by using imprint method to form the antireflection coating layer on the cells and investigate their effect. The triangular shape micro-prism formed by EPOXY is the best result and can reduce the reflectivity to 11%. And enhance the conversion efficiency for about 28%. Finally we try to adopt the ZnO nanowire grown on the solar cell by using chemical bath deposition method to evaluate the influence of the solar cell. The best result of this method can reduce the reflectivity to 10%. And the conversion efficiency can be enhanced to about 42%. Then we compare all three types of antireflection coating on the GaAs solar cells to find the best result tof conversion efficiency enhancement.
The antireflection coating layer can easily improve the conversion efficiency of solar cells and make them more popular in our daily life. As a result this technology will make the dream of green world more promising.

Chapter 1
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Chapter 2
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Chapter 3
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Chapter 4
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Chapter 5
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Chapter 6
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[6.3] Aleksandra B. Djurisˇi and Yu Hang Leung “Optical Properties of ZnO Nanostructures” Small, Vol. 2, No. 8-9, pp.944–961, 2006
[6.4] W.J. Fan, and X.B.Xia “Band parameters and electronic structures of wurtzite ZnO and ZnO/MgZnO quantum wells” Journal of Applied Physics, Vol.99, pp.013702, 2006
[6.5] Ming-liang Kao “The fabrication and study of ZnO/MgO core-shell nanowire transistors” NCKU: Department of Chemical Engineering, 2009
[6.6] Jing-Shun Huang “Influences of ZnO sol-gel thin film characteristics on ZnO nanowire arrays prepared at low temperature using all solution-based processing ”Journal of Applied Physics ,Vol.103, pp.014304, 2008