本論文的研究目的是藉由氧化銦作為和p型氮化鎵的接觸層以降低氮化鎵發光二極體的順向導通電壓，進而達到改善氮化鎵發光二極體的亮度。氧化銦錫雖然已被廣泛的應用在氮化鎵系發光二極體作為透明導電層，但氧化銦錫和p型氮化鎵不具有良好的歐姆接觸以致於特徵接觸電阻偏高，使得氮化鎵發光二極體順向導通電壓偏高，遂使氮化鎵發光二極體效率降低。
氧化銦具有高透光性，高能隙(3.75 eV)等特性，是做為透明導電層的良好材料，本實驗是以電子束蒸發器為蒸鍍源，依序蒸鍍氧化銦及氧化銦錫在p型氮化鎵上作為氮化鎵發光二極體的透明導電電極。
本實驗中，我們比較採用氧化銦錫及氧化銦/氧化銦錫之不同結構p型透明電極發光二極體的光電特性，實驗結果顯現具有氧化銦/氧化銦錫結構之透明導電層發光二極體有較低的順向導通電壓及較高的發光效率。
此外，為了增加更多的光取出，我們在所研製的透明導電層上採用微影及濕蝕刻的方式，在透明導電層上蝕刻出具有直徑3微米，深度47奈米，孔洞與孔洞的間隔為3微米之圓形孔洞圖型，與平坦的透明電極比較，具有圓形孔洞圖型之透明電極發光二極體，有較高的出光效率，但也具有較高的順向導通電壓。

The purpose of this research is to lower the forward turn-on voltage of the GaN-based LED by using In2O3 as the contact layer to p-GaN, and then improve the luminous intensity of the GaN-based LEDs. Although the ITO has broadly applied to GaN-based LEDs as the transparent current spreading layer, however, ITO on p-GaN shows poor ohmic characteristics, which increases the specific contact resistance and makes the forward turn-on voltage of GaN-based LEDs larger, and consequently lowers the luminous intensity of the GaN-based LEDs.
In2O3, with features such as high transmittance, and high band gap, is an excellent material for current spreading layer. This experiment used E-beam as the deposition technology to deposit the In2O3 and ITO on p-GaN, respectively, as the transparent current spreading layer of GaN-based LEDs.
In this thesis, we compare the GaN-based LEDs with In2O3/ITO and ITO p-electrodes. From the results of the experiment, the LED with In2O3/ITO electrodes shows lower operation voltage and higher luminous intensity.
Moreover, we create the 3 μm hole-diameter, 3 μm spacing and 47 nm depth pattern by using photolithography and wet-etching process in order to extract more light out diffuse. Compared with the planar LED, the hole-patterned LED shows higher EL intensity but higher operation voltage.

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