本研究運用聚焦離子束(FIB)在不同的離子束蝕刻深度、電流滯留時間和不同密度二維的點陣圖，於傳統的薄膜式發光二極體表面製作出三維的柱狀發光二極體結構。因FIB高能量的鎵離子束易破壞柱狀發光二極體表面氮化鎵結晶性，產生具有缺陷的非晶層，吾人使用氫氧化鉀/乙二醇溶液，運用其對氮化鎵材料的方向有選擇性蝕刻，進而去除柱狀發光二極體表面的非晶層，留下結晶性良好的柱狀發光二極體，使得從主動層放出的光子能夠有效釋放至空氣中。由陰極射線螢光光譜(CL)可觀察到柱狀發光二極體發光強度較傳統薄膜式發光二極體增強2.85倍。
於微米級的光致發光光譜(micro-PL)可觀察到氮化銦鎵的發光波長會有藍移117 meV的現象且發光強度會增強1.5倍。前者是因為柱狀發光二極體能夠釋放因磊晶過程中產生的應力，使壓電場極化效應減弱。此外受到內部電場影響，電子的波函數減弱，因此電子需要更大的能量才能從價帶跳到傳導帶，而使得空間的量子侷限效應增強。後者為當發光二極體為柱狀結構時，其表面為拋物線狀，則光較易從柱狀結構表面釋放，而不似薄膜結構易在發光二極體內部產生全反射。
從發光二極體從薄膜製作成柱狀結構，不僅受到離子束轟擊和濕式蝕刻的影響，也受到後續填入SOG、ITO以及電極的覆蓋等不同材料，然而光萃取效率卻有顯著的提昇，這些原因將會影響元件的理想因子、串聯電阻、光輸出功率和外部量子效應的表現。

The research utilized focused ion beam (FIB) fabricating rod-typed light emitting diodes (LED) by changing the ion beam milling depth, dwell time, and the bitmap patterns on the conventional thin film LED. However, FIB had high energy of gallium ions which damaged the GaN crystallinity on the surface of rod-typed LED. We used the KOH/ Ethyl Glycol etchant in order to remove the amorphous layer and remain high crystal quality of the rod-typed LED. This etchant was able to practice selective etching on z-axis of GaN. Due to chemical wet etching, photons from the active layer of the rod-typed LED emitted easier than conventional LED, and the intensity increased by the factor up to 2.85 in CL spectrum.
It is observed in the micro-photoluminescence (micro-PL) spectrum that there was a blue shift of 117meV on the InGaN wavelength and the intensity enhancement of light emission by a factor of 1.50. The former was caused by the reduction of piezoelectric field polarization because rod-typed LEDs were able to release the stress which formed by MOCVD epitaxial technology. Besides, the electronic wave functions of internal electron field diminished that electrons needed more energy to jump from the valence band to the conduction band, and the quantum confinement effect increased. The latter was formed by parabolic surface on the rod-typed LEDs. The light escaped from the surface of the rod-typed LEDs easier than from thin film, and the light had not tendency to total reflection comparing to the thin film LED.
The rod-typed LED was built on the conventional LED, and it was not only affecting by ion beam milling and chemical wet etching, but also by capping different materials, such as SOG, ITO, and pads. Those reasons played important roles on the ideality factor, series resistance, light output power, and external quantum efficiency.

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