於此篇論文中，主要研究以氮化鎵/氮化鋁鎵/氮化鎵結構研製蕭特基式氫氣感測器，由於氮化鎵及氮化鋁鎵與砷化鎵、矽材料等相比有著較寬的能隙，且物理、化學性質、熱穩定性也是其特點，而接面處所存在的二維電子氣(2-DEG)更使氮化鎵/氮化鋁鎵/氮化鎵基底的感測器有著良好的感測能力。並在蕭特基感測區之下以過氧化氫表面氧化處理的方式生成自然氧化層，此氧化層能夠有效的降低元件於空氣中的穩態電流及逆偏電流，使得感測特性獲得改善。
而在催化金屬(鈀、鉑)方面上利用快速蒸鍍法製造鉑、鈀奈米粒子在相反金屬薄膜上以形成雙金屬結構。結果顯示修飾後以奈米粒子的雙金屬結構蕭特基氣體感測器在氫氣之反應響應及速度皆有大幅提升。此方法提升了單一金屬粗糙度不足的問題，利用與之相反的金屬做修飾提升溢出效應。
最後章節則利用快速對流沉積法(RCD)塗上二氧化矽奈米球，於此之上再蒸鍍上一層鈀薄膜，利用兩層修飾的方式大幅增加表面粗糙度及吸附座，增加元件的吸附力。且也附上單修飾二氧化矽奈米球之感測特性確保不會阻擋氫氣的進出且能增加溢出效應的功能。自然氧化層、雙金屬結構跟二氧化矽奈米球等修飾方法使漏電流降低、吸附座增加、粗糙度提升皆有利於元件的感測響應、速度等效果。

In this thesis, the main research is to develop a Schottky hydrogen sensor with a GaN-based structure, and the native oxide layer by surface treatment on the Schottky sensing region. In addition, platinum and palladium nanoparticles are produced by a rapid and proper vacuum thermal evaporation (VTE) approach method on a catalytic metal (palladium, platinum) film to form a bimetallic structure. The results show that the Schottky gas sensor with nanoparticle structure has a significant promotion in the response and response(recovery) time of hydrogen.
Compared with other materials (e.g. GaAs, Si), GaN (AlGaN) series material have a wide band gap, high temperature stability, and physical, chemical stability. Furthermore, the GaN/AlGaN heterojunction has a two-dimensional electron gas (2-DEG). Therefore, those gas sensors perform excellent sensing capabilities and a wide operating temperature.
The nanoparticle is fabricated by rapid evaporation to form a bimetallic structure. This method can rapidly fabricate the Schottky contact surface and reduce the number of process steps. Furthermore, in terms of sensing characteristics, the addition of the nanoparticle structure enhances the roughness, surface-volume ratio, and reduces the energy, which is required for adsorption in gas sensing. The SiO2 nanosphere (NS) and Pd nanoparticles also provide the same benefit to improve roughness and adsorption capacity Moreover, the surface treatment of hydrogen peroxide (H2O2) forms a native oxide layer (GaOX), which can significantly decrease the reverse bias leakage current of the device and apply more the adsorption site to achieve the effect of improved sensing characteristics.

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