本論文主要研究以有機金屬化學氣相沉積法進行氧化鎵磊晶膜的成長，成長在(0001)藍寶石基板上。以不同的成長條件來探討對氧化鎵薄膜品質的影響，藉由調變腔體溫度、磊晶時腔壓、參與反應的氧氣流量來研究對磊晶膜品質的影響，試著選擇出較佳的成長參數。分析後發現最佳化參數為腔壓15 Torr、氧氣流量200 sccm，製程溫度500℃，接著將之製作成光電元件，並對元件作電特性分析與探討。
經由XRD & PL薄膜分析發現製備完成的磊晶膜為單斜氧化鎵薄膜，最強波峰位於(4 0 2 )面，穿透率在260 nm~1000 nm平均約為92 %。能隙約為4.8 eV，進一步以沉積後金屬退火方式來分析薄膜特性，分別以大氣下退火、O2 環境下退火、N2環境下退火、與不進行退火，使用光子激發光光譜法(PL)和高解析度X-射線繞射儀做分析發現，氮氣退火後我們發現氮氣退火確實對薄膜品質有提升的效果。
製備完成氧化鎵薄膜後，我們接著製作成金半金光檢測器，以光響應頻譜分析發現氮氣退火後的薄膜製成光偵器，對於漏電流有改善現象，由退火前的1.6×10-12下降至退火後的1.2×10-13，降幅達1個數量級。光響應度的部分也有所提升。退火前最大響應度為0.0325A/W，氮氣退火後最大響應度為0.4375A/W，可以說明氮氣退火對於改善元件電特性是有效的。
經由量測結果發現，元件在短波光的波段有不錯的操作特性，證明可以應用做為UV光偵測器。

This thesis focuses on growth of gallium oxide epitaxial film used metal organic chemical vapor deposition technology. Deposited on c-plane (0001) sapphire.I use a different growth conditions to discuss the impact on the quality of gallium oxide films. Changing the deposition temperature、chamber pressure, and oxygen flow to study the influence of the epitaxial film quality,try to choose a better growth parameters.After analysis, the optimized parameters: chamber pressure 15Torr、Oxygen flow 200 standard cubic centimeter per minute (sccm)，Process temperature 500℃. Then a metal-semiconductor-metal solar-blind deep ultraviolet photodetector was fabricated on the β-Ga2O3 epilayer.
The epilayer was grown on (0001) sapphire substrate using modified Emcore D180 MOCVD system.The metal organic source is TEGa, chemical reaction gas is oxygen. The as-grown β-Ga2O3 epilayer was annealed at 800 ºC in atmosphere or Oxygen or Nitrogen. Influence of surface states and point defects of β-Ga2O3 epilayers before and after N2 annealing are studied using room-temperature Photoluminescence (PL) and HR-XRD.We have shown that annealing single-crystalline β-Ga2O3 epilayer in Nitrogen atmosphere at 800 ºC can heal its surface states and point defects without disturbing crystal structure and quality.It also can improve the MSM photodetector performance of dark current and responsivity.

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