本論文主要研究不同金屬摻雜於氧化鋅奈米柱結構的光電特性與其應用。依不同摻雜金屬，本論文可分為兩部份。第一部份為探討銦摻雜於氧化鋅奈米柱之成長、其元件製做及量測，第二部份則研究鎵摻雜於氧化鋅奈米柱之成長、其元件製做及量測。
首先，我們利用水熱法成長銦摻雜的氧化鋅奈米柱，經由電子顯微鏡(SEM)及電子穿透顯微鏡(TEM)結果指出，所成長出的氧化鋅奈米柱呈現六角纖鋅鑛晶體結構。再由能量色散X-射線光譜儀測出銦元素，證明了成功將銦摻雜於氧化鋅奈米柱中。基於此成長方法，我們製做了光檢測器、溼度感測器及場發元件。光檢測器元件方面，我們發現不同偏壓操作下，其臨界波長均為390nm。在1V的偏壓下，紫外光-可見光抑制比達到兩個數量級之多，另其雜訊等效功率(noise equivalent power)和光檢測度(detectivity)分別為1.42×10−10 W 及 1.44×1011cmHz0.5W−1。濕度感測方面，暗電流會隨著環境溼度增加而增加，暗電流在RH30度時為7.82*10-6Ａ，但當溼度增加到RH70時，暗電流為6.045*10-4Ａ。場發元件方面，經量測發現，其臨界電壓為0.8V/um且場發射因子β為9818.
再來我們研究鎵摻雜於氧化鋅奈米柱之光電特性及場發特性。經由X-射線光電子光譜儀(XPS)分析，Ga 2p3的束縛能為1118.1eV，證明了鎵元素的成功加入氧化鋅奈米柱中。我們製做了場發元件，並發現其臨界電壓為3.6V/um 且場發射因子β為9058.

In this study, we report the different metal doped-on ZnO nanorods and its applications. This dissertation is divided by two parts due to different metal doped. First, we study the growth of indium doped in ZnO nanorods, the fabrication of its application devices and analyze it. And then, gallium doped ZnO nanorods-based devces are investigated.
In the beginning of the dissertation, we synthesize indium doped ZnO nanorods using hydrothermal method and fabricate MSM UV photodetector, humidity sensor and field emitter. The field emission scanning electron microscopy (FESEM) and field emission transmission electron microscopy (FETEM) results indicate that the nanorods exhibited single crystal with hexagonal wurtizite structure. Moreover, the energy dispersive X-ray spectroscopy result shows that the indium was successfully doped in ZnO nanorods. It was found that the cut-off frequency was 390nm while biased different voltage at UV photodetector. When biased at 1V, the UV-to-visible rejection ratio of the PD was approximately 109. For a given bandwidth of 1 kHz and biased of 1V, the results showed that the noise equivalent power (NEP) and detectivity(D*) were 1.42 ×10−10 W and 1.44 ×1011 cm•Hz0.5•W−1. While measuring their humidity properties, it was found that the current is about 7.82*10-6 A at RH30 increased to 6.045*10-4 A at RH70 under without UV illumination. The threshold voltage of fabricated field emitter was 0.8V/um and field enhancement factor β was 9818.
And then, we investigate the optoelectrical properties of the gallium doped ZnO nanorods and field emission properties. The X-ray photoelectron spectroscopy (XPS) results of the nanorods showed that the binding energy of the Ga 2p3 is 1118.1eV. It indicates that O-Ga bond was indeed incorporated into these nanorods. Field emitter was fabricated on glass substrate and using gallium doped ZnO nanorods. It was found that the threshold voltage and field enhancement factor β are 3.6V/um and 9058 respectively.

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