在本論文中，主要探討以氮化鎵/氮化鋁鎵/氮化鎵結構研製蕭特基式氣體感測器，並在感測區域以表面處理的方式生成自然氧化層。另外在催化金屬(鈀、鉑)薄膜上利用紫外光還原氯化鈀(PdCl2)或氯鉑酸(H2PtCl6)還原出鈀、鉑奈米粒子結構。其結果顯示具奈米粒子結構之蕭特基氣體感測器在氫氣與氨氣感測靈敏度方面皆大幅提升。
與其他材料(如砷化鎵系、矽)相比，氮化鎵/氮化鋁鎵具有寬能隙能帶、良好熱穩定性及物理、化學性質穩定之特點，且在氮化鎵/氮化鋁鎵異質接面具有二維電子氣（2-DEG）。因此以其材料研製之氣體感測器展現優秀的感測能力與寬廣的操作溫度。
　本論文利用紫外光製作奈米粒子結構，相較於傳統熱蒸鍍製程等，此方法可縮短製程時間、漸少製作蕭特基接面時的耗能。另外，在感測特性方面，加入奈米粒子結構亦提升感測區域之粗糙度及體表面積比，降低氣體感測中吸附所需之活化能以提升感測倍率。此外，利用過氧化氫之表面處理形成自然氧化層（GaOx），可顯著降低元件漏電流並增加吸附座以達到提升感測能力之效果。

In this thesis, the GaN/AlGaN/GaN-based Schottky gas sensor was fabricated and studied, the native oxide layer formed by surface treatment on the detection region. Furthermore, palladium chloride (dihydrogen hexachloroplatinate (IV) hexahydrate) used for reducing the catalytic metal Pd (Pt) nanoparticle by UV expose process. In this work, the sensing performance substantially enhance not only to hydrogen but to ammonia.
Compare to previous studied (e.g. GaAs, Si), GaN (AlGaN) series material exhibit wide energy gap, high temperature stability, and physical, chemical stability. In addition, two-dimension electron gas (2DEG) exist in GaN/AlGaN heterojunction, which is benefit for hydrogen sensing. With these advantages, the Schottky gas sensor based on GaN/AlGaN present excellent sensitivity and wide detection temperature.
Different form traditional evaporate plating (EP), the nanoparticle formed by UV exposed process spend shorter time and less energy consume. Furthermore, detection region with nanoparticle enhance surface-volume ratio and roughness, which cause the lower activation energy of hydrogen sensing reaction contribute to detection characteristic improve. Besides, the native oxide layer formed by hydrogen peroxide (H2O2) treatment apply more adsorption site and decrease the reverse bias leakage current

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