本論文主要對氧化銦錫 (Indium-Tin-Oxide, ITO) 與 n 型氮化鎵 (GaN) 之間的掘入式歐姆 (Ohmic Recess) 接觸特性進行探討，於實驗中我們利用乾蝕刻技術，實作出不同歐姆掘入深度的氮化銦鎵量子井 (InGaN Single Quantum Well) 全透明發光高電子遷移率電晶體 (Light-Emitting High Electron Mobility Transistor, LE-HEMT)。
從實驗結果中我們發現，當歐姆掘入深至二維電子氣 (Two-Dimensional Electron Gas, 2DEG) 位置附近時，ITO 的電流-電壓特性中存在的能障值會下降至接近 0 V，但掘入式歐姆 ITO 電極不論是透過載子穿隧導通或是與 2DEG 直接側向接觸導通接觸阻抗都極大，導致全透明元件電流大小比做為實驗對照組的鈦/鋁/鈦/金 (Ti/Al/Ti/Au) 歐姆電極元件還要小超過兩個數量級。且全透明 LE-HEMT 因為接觸特性差所以電流較小，因此亮度和 Ti/Al/Ti/Au 歐姆電極 LE-HEMT 相比之下較為黯淡。
而實驗結果也顯示當 Ti/Al/Ti/Au高電子遷移率電晶體 (High Electron Mobility Transistor, HEMT) 其歐姆掘入深度在未將氮化鋁鎵完全蝕刻時，接觸阻抗會與掘入深度增加呈現負相關的趨勢。

In this work, properties of recessed ohmic contacts using Indium-Tin-Oxide (ITO) on n-type GaN are investigated. Fully transparent light-emitting high electron mobility transistors (LE-HEMT) were fabricated with different recess depths for ohmic contacts by using dry etching technology.
From experiment results, it is concluded that the value of an offset voltage exhibited in the I-V curves reduces to zero when recessed contact metal is closer to the two-dimensional electron gas (2DEG). However, the contact resistance remains large either the ITO electrode is conducted by tunneling with a thin barrier or in direct contact with 2DEG on sides, which results in a current magnitude of fully transparent devices less than 1/100 times of the reference devices with Ti/Al/Ti/Au electrodes. Because of the poor contact characteristics of the fully transparent LE-HEMT, it also shows a lower light intensity than a Ti/Al/Ti/Au electrode LE-HEMT.
The experimental results also show that for the Ti/Al/Ti/Au HEMT, when the AlGaN at the contacts is partially-recessed instead of over-etched, the contact resistance decreases as the etch depth is increased.

中文摘要.............................................................i
Abstract............................................................ii
目錄...............................................................iii
圖目錄..............................................................vi
表目錄...............................................................x
1 第一章 序論........................................................1
1.1 前言.............................................................1
1.2 氮化鎵材料特性介紹................................................2
1.2.1 自發極化效應....................................................2
1.2.2 壓電極化效應....................................................3
1.2.3 氮化鋁鎵/氮化鎵異質接面..........................................4
1.2.4 P 型氮化鎵閘極..................................................5
1.3 文獻回顧.........................................................6
1.3.1 氮化鎵發光二極體................................................6
1.3.2 電晶體與氮化鎵二極體單片集成.....................................8
1.3.3 透明薄膜電晶體.................................................10
1.3.4 歐姆掘入蝕刻...................................................12
1.4 研究方向及架構...................................................14
1.4.1 研究方向......................................................14
1.4.2 論文架構......................................................14
2 第二章 關鍵製程與原理簡介...........................................15
2.1 氧化銦錫........................................................15
2.2 發光元件........................................................15
2.3 電子阻擋層 (Electron Blocking Layer, EBL).......................16
2.4 關鍵製程........................................................17
2.4.1 P型氮化鎵乾蝕刻製程............................................17
2.4.2 歐姆掘入蝕刻...................................................18
2.4.3 ITO電極濕式蝕刻................................................19
2.4.4 快速熱退火製程 (Rapid Thermal Annealing, RTA)..................19
3 第三章 元件製程....................................................21
3.1 磊晶結構........................................................21
3.2 元件製程........................................................24
3.2.1 試片清潔......................................................24
3.2.2 對準記號蝕刻...................................................24
3.2.3 p-GaN 蝕刻....................................................26
3.2.4 氧離子佈植元件隔離.............................................28
3.2.5 歐姆掘入蝕刻...................................................30
3.2.6 ITO 薄膜沉積..................................................32
3.2.7 ITO 薄膜蝕刻..................................................33
3.2.8 源極/汲極歐姆接觸金屬..........................................34
3.3 元件規格與俯視圖.................................................36
3.3.1 元件規格......................................................36
3.3.2 元件俯視圖....................................................37
4 第四章 量測結果與分析..............................................39
4.1 源極/汲極掘入蝕刻 D-mode 前導片...................................39
4.2 A 結構與 B 結構量測..............................................42
4.2.1 Ti/Al/Ti/Au 5 µm nTLM.........................................42
4.2.2 ITO 5 µm nTLM.................................................47
4.2.3 直流電性量測與分析.............................................54
4.2.4 電致發光量測...................................................63
5 第五章 結論及未來展望..............................................66
6 參考文獻..........................................................67

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