氧化鋅(ZnO)為一具有寬能隙(室溫下約3.37 eV)直接能隙半導體，且在室溫下60 meV 之激子束縛能相較於氮化鎵(GaN)來的更穩定，因此在室溫下非常適合做為光電元件之應用。
本論文利用化學氣相沈積方式在石英管式高溫爐內成長銦摻雜氧化鋅奈米柱。銦可用來增加其電特性，並做為N型雜質。銦摻雜氧化鋅奈米柱之形成機制為經由氣-液-固(vapor-liquid-solid, VLS)方式成長，並藉著控制高溫爐內氣體流量、壓力、溫度...等條件，成長出銦摻雜氧化鋅奈米柱結構。本研究利用鋅粉及銦顆粒做為原料透過高溫爐之氣相方式沈積，並經由氬氣的載流及與氧氣結合而沈積於基板上，進而形成銦摻雜之氧化鋅奈米柱結構。
由實驗結果可知，不同的溫度梯度會影響奈米柱的形貌與尺寸，以場發射掃描式電子顯微鏡觀察銦摻雜之氧化鋅奈米柱結構，發現其形貌呈現六角柱形狀。並藉由X射線繞射儀(XRD)量測其結晶型態，此外隨著銦含量的增加其結晶性也隨之下降。藉由光激發光譜(PL)可得知隨著銦含量增加，光譜有紅移之現象且氧化鋅於380 nm發光波段之強度也隨之變弱。
藉由酒精溶液，將所成長之氧化鋅奈米柱粉末使其可以橫跨指叉狀電極的兩端，於室溫下量測可發現其電特性有一個負微分的現象，而且開關電流比約為3.3:1。最後，我們在發光二極體上成長氧化鋅奈米柱，希望藉由氧化鋅奈米柱可增加出光效果，由實驗結果發現在有無奈米柱結構之發光二極體其電特性僅有些微的影響，但由於形成奈米柱前會先沈積一層較厚之氧化鋅薄膜，因此降低了發光二極體之出光效果，之後將會進行此部份特性改善。

Zinc oxide (ZnO) is a wide direct bandgap (3.37eV) semiconductor at room temperature, and its exciton binding energy of 60 meV is larger than that of GaN (25meV). ZnO materials can be expected to be used in optoelectronic devices due to its advantageous properties.
In this study, indium was used to improve the electrical properties and acting as an N-type dopant.. In-doped ZnO nanorods were fabricated in the quartz tube furnace by using self-catalyst vapor-liquid-solid (VLS) growth mechanism and chemical vapor deposition (CVD) method. By controlling the gas flow, pressure, and temperature, various properties of In-doped ZnO can be obtained.
According to the experimental results, we found that the various temperature gradients would affect the morphology of nanorods by using field-emission scanning electron microscopy (FE-SEM). Using X-ray diffraction (XRD) measurement, ZnO nanorods present the hexagonal structure and the intensity of [002] plane decreased with increasing the content of indium. According to the photoluminescence (PL) spectra, the near band edge emission at 380 nm decreased while the content of indium increased. The excitonic emission at the at the UV range shift to the longer wavelength with increasing indium content.
Using ethanol solution, the nanorods were put across two metal pads. The negative differential behavior property of ZnO nanorods can be obtained from I-V measurement. Finally, the nanorods were put on light emitting diodes to eahance the light-output intensity. Although the turn-on voltage keep almost the same value compared to the conventional diode, the light-output intensity decreased due to the thick ZnO film formation before the nanorods deposition.

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