在本論文中，吾人研製一系列氮化鎵/氮化鋁鎵蕭特基二極體式氫氣感測器元件，並在感測區域分別以過氧化氫處理在氮化鎵表面生成自然氧化層及利用紫外光還原氯化鈀(PdCl2)形成之鈀奈米粒子來製作元件，結果發現可大幅的提升感測器元件的靈敏度，並量測在空氣中通入氫氣濃度及控制濕度時元件之電性及特性。
首先，吾人研製出三種由氮化鎵/氮化鋁鎵系不同結構未經處理之蕭特基二極體式氫氣感測元件，由於氮化鎵及氮化鋁鎵皆是具有寬能隙之材料，所以製作出的感測器能夠擁有良好的熱穩定特性且具備廣泛的溫度操作範圍及良好的感測特性。
接著，選出最佳感測特性之元件做後續的表面處理；利用紫外光所製作出的鈀奈米粒子不僅可以減少製作蕭特基接觸時的耗能，來研製出感測器，且也可應用在一般的感測器上使蕭特基金屬薄膜表面形成奈米結構，大大的增加了感測面積及氣體的感測特性。最後利用過氧化氫對氮化鎵表面進行氧化反應，形成自然氧化層(GaXOy)增加了蕭特基能障，藉此以降低空氣中的穩態電流提升氣體感測的特性。

In this thesis, the series of GaN/AlGaN-base Schottky diode hydrogen sensors have been fabricated and studied. The native oxide (GaxOy) formed on GaN surface by H2O2 treatment and UV fabrication of palladium nanoparticles are used on Schottky sensing area to improve sensing performance. The steady-state and transient-state characteristics of device are measured under different hydrogen concentration and humidity in and air atmosphere.
Firstly, three different structure of GaN/AlGaN Schottky diode-type hydrogen sensor without treatment are fabricated and demonstrated. Because the GaN/AlGaN materials have wide band gap, the Schottky diode-type hydrogen sensors can stablely operate at higher temperature and then the best sensing performance of sensor device will be processed for subsequent research. UV fabrication of Pd nanoparticle not only decrease energy consumption for making Schottky contact but also use on general hydrogen sensor to increase sensing area. Finally, the native oxide (GaxOy) layer formed on GaN by H2O2 treatment and combined with aforementioned research.

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