本論文主要是探討透過爐管氧化製程將藍寶石基板(sapphire)上磊晶製作出來的氮化鋁鎵(AlxGa1-xN)試片其中鋁含量為x=0.27，在高溫熱氧化(oxidation)的過程中將其氧化成氧化鋁鎵β-(AlxGa1-x)2O3。並且成功的製作出高鑑別率(high rejection ratio >1000 @220nm/@360nm)短波長選擇性蕭特基二極體(SBD)光偵測器。

　　為了探討高溫氧化製程中不同溫度不同時間的條件下，對氮化鋁鎵氧化層的厚度與光電特性變化差異，本論文採用爐管在環境溫度850℃、900℃、950℃氧氣流量10000 sccm 下分別進行1、2、3 小時不同時間的高溫氧化製程。並且透過一系列基礎分析來對氧化物做基礎研究。如:利用掃描電子顯微鏡(SEM)確認其氧化層厚度；X射線繞射分析儀(XRD)進行衍射峰的交叉比對氮化鋁鎵/氧化鋁鎵/氧化鎵的晶相位置，最後是X射線光電子能譜儀(XPS)來作為分析元素化學態和電子態的定量分析。接續氧化製程後沉積鎳(Ni)/金(Au) (4nm/10nm)作為氧化鋁鎵蕭特基接面金屬-半導體接面金屬。並透過黃光微影與感應耦合電漿-離子蝕刻(ICP)，蝕刻出高台並使N型氮化鎵(n-GaN)裸露出來。最後蒸鍍上金屬襯墊Ti/Al(30nm/300nm)即完成元件製程。

　　在光電特性中，元件在不同製備溫度條件下其漏電流最低可達10-6 A/cm2，而串聯電阻(TLM)在850℃、900℃時為10-4 Ohms/cm2，但在950℃時提升為10-3 Ohms/cm2，表明金-半接面的串聯電阻在熱氧化的過程中會隨著溫度與時間的增加而增加。而在光響應特性中，以氧化溫度950℃氧化時間1小時所體現出來的光響應鑑別率(rejection ratio)最佳。

關鍵字:氮化鋁鎵、氧化鋁鎵、高溫熱氧化、光響應、鑑別率、蕭特基二極體

In this study, we propose a β-(AlxGa1-x)2O3 (x=0.27) Schottky barrier diode ultraviolet photodetector with furnace tube oxidation and we using 300nm AlGaN type A structure and different high temperature thermal oxidation condition to made AlGaN thin film convent to β-(AlxGa1-x)2O3 .In this work our device responsivity measurement results show the great PCDR and rejection ration can arrived 3 order it’s mean rejection ratio>1000 @220nm/@360nm, with oxidation condition 950℃ 1hr.Thus, we successfully produced a SBD ultraviolet photodetector with high wavelength selectivity.

Key words: AlGaN, β-(AlxGa1-x)2O3, thermal oxidation, responsivity, rejection ratio, Schottky barrier diode

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