由於太陽能源的收集和面積有著極大的關係，在固定的轉換效率之下，面積越大所能收集的能量將越大，而元件面積越大，將電流導出的金屬線面積也就越大，所需的金屬材料就越多，進而所需的製造成本就相對提高。過去，在砷化鎵上常使用的金屬材料為金，然而金為貴重金屬，價格昂貴，為降低砷化鎵系列太陽電池的製造成本，在本研究中，吾人嘗試以銀、鋁、銅為主體材料在重摻雜的n-型砷化鎵上製作歐姆接觸電極，並探討其熱穩定性。
在重摻雜n-型砷化鎵上蒸鍍三種不同的金屬組成，分別為Ni/Ag/Au、Ni/Al/Au與Ni/Cu/Au，將試片分成數批經歷不同的退火條件，接著利用傳輸線模型(TLM)量測其金屬材料和半導體之間的接觸特徵電阻(ρc)，以X光繞射儀(XRD)探討金屬材料和半導體之間的界面相互擴散情形。

Heavily doped n+-GaAs material plays important role in optoelectronics for the formation of ohmic contacts. Gold always is the popular metal for the electrode formation in the fabrication of optoelectronic devices. Regarding to solar cells, about 10% of cell area is covered with metal electrodes. In order to reduce the fabrication cost, cheaper metals shall be adopted for the formation of metal electrodes on solar cells. In this work, three kinds of metal combination, including Ni/Ag/Au, Ni/Al/Au, and Ni/Cu/Au, were deposited on n+-type GaAs to form non-alloyed ohmic contacts and be characterized, respectively. All samples were thermal treated with various different temperatures and times to evaluate the thermal stability.
The characteristic contact resistances (ρc) were characterized by transmission line model (TLM). The inter-diffusions between metal and semiconductor after thermal treatment were characterized by X-ray diffractometer (XRD).

封面內頁
簽名頁
授權書．．．．．．．．．．．．．．．．．．．．．．．．．iii
中文摘要．．．．．．．．．．．．．．．．．．．．．．．．iv
英文摘要．．．．．．．．．．．．．．．．．．．．．．．．v
誌謝．．．．．．．．．．．．．．．．．．．．．．．．．．vi
目錄．．．．．．．．．．．．．．．．．．．．．．．．．．vii
圖目錄．．．．．．．．．．．．．．．．．．．．．．．．．ix
表目錄．．．．．．．．．．．．．．．．．．．．．．．．．xii

第一章　序論
1.1 前言．．．．．．．．．．．．．．．．．．．． 1
1.2 研究背景與動機．．．．．．．．．．．．．．． 1
1.3 本文架構．．．．．．．．．．．．．．．．．． 2
第二章　理論介紹．．．．．．．．．．．．．．．．．．．． 3
2.1 太陽電池介紹．．．．．．．．．．．．．．．． 3
2.1.1 太陽電池之理論．．．．．．．．．．．．． 3
2.1.2 太陽電池分類．．．．．．．．．．．．．．8
2.1.3 砷化鎵太陽電池的優點．．．．．．．．．．11
2.2金屬與半導體接觸理論．．．．．．．．．．．． 12
2.2.1 歐姆接觸理論．．．．．．．．．．．．．．19
2.2.2 電流傳導機制．．．．．．．．．．．．．．20
2.2.3 砷化鎵歐姆接觸技術．．．．．．．．．．． 22
2.3 傳輸線模型理論．．．．．．．．．．．．．．．24
第三章 元件實驗內容．．．．．．．．．．．．．．．．．．27
3.1 歐姆接觸製程．．．．．．．．．．．．．．．．27
3.2 相關儀器設備．．．．．．．．．．．．．．．． 32
3.2.1 有機金屬氣相磊晶．．．．．．．．．．．． 32
3.2.2 微影製程．．．．．．．．．．．．．．．． 33
3.2.3 蒸鍍機．．．．．．．．．．．．．．．．． 36
3.2.4 X光繞射儀．．．．．．．．．．．．．．．38
第四章 結果分析與討論．．．．．．．．．．．．．．．．．41
4.1 TLM比較．．．．．．．．．．．．．．．．．．41
4.2 XRD比較．．．．．．．．．．．．．．．．．．49
第五章 結論．．．．．．．．．．．．．．．．．．．．．．59
參考文獻．．．．．．．．．．．．．．．．．．．．．．．．60

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