本研究中，我們在n-GaN/Sapphire基材上以自組裝的有機金屬化學氣相沈積（Metal Organic Chemical Vapor Deposition, MOCVD）系統成長氮化鎵(GaN)、氮化銦鎵(InXGa1-XN)和氮化鋁銦鎵(AlInGaN)薄膜，對於薄膜的特性分析，則利用場發射掃描電子顯微鏡(FE-SEM)、X光繞射分析儀(XRD)、X射線光電子能譜儀(XPS)和光激發螢光光譜儀(PL)。
首先以探討成長氣壓對GaN薄膜的影響，在固定所有的成長參數下改變不同的成長氣壓，隨著成長氣壓的降低，可改善薄膜的品質和增加成長速率，在成長氣壓為25 torr時有較好的薄膜品質。接著在InXGa1-XN薄膜的成長中，發現降低成長氣壓或溫度及增加TMIn/(TMIn＋TMGa)進料流量比或成長時間都可提高InXGa1-XN薄膜中的銦含量，並利用以上參數成長出一系列高銦含量、單一X光繞射峰的InXGa1-XN(0.17≦X≦0.45)薄膜，使用XPS分析元素成份比與XRD推算出來的結果是一致的。
對於AlInGaN薄膜成長方面，固定TMIn/(TMIn＋TMGa)進料流量比，增加三甲基鋁(TMAl)的進料，當TMAl進料增加，晶格常數會變小。
最後利用AlInGaN當緩衝層來降低高銦含量的InGaN與GaN間的晶格不匹配，只要多了30 nm 厚度的AlInGaN緩衝層，其繞射角都會往左位移，造成銦含量增加，這樣的結果推測是因為張力緩衝層發揮效果，使得高銦含量的InGaN更容易長成。然後使用AlInGaN當纖衣層成長多對In0.43Ga0.57N/AlInGaN薄膜結構，發現薄膜的XRD圖形是由兩個繞射峰合成，且繞射峰對應的繞射角和原本In0.43Ga0.57N和AlInGaN的繞射角有些許不同，推測可能是因多層結構造成晶格應力互相影響，以及在成長時接面處會有Al、Ga、In互相擴散的結果。

In this study, we have grown gallium nitride (GaN), indium gallium nitride (InGaN), and aluminum indium gallium nitride (AlInGaN) thin films on the n-GaN/Sapphire substrates by employing a home-made metal organic chemical vapor deposition (MOCVD) system. The material properties of these samples were characterized by using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS) and Photoluminescence (PL).
At the beginning, we explored the effect of the growth pressure for the GaN thin films. We improved thin film’s quality and increased the growth rate by reducing the growth pressure down to 25 torr. In InXGa1-XN thin film growth, we found the indium content in InXGa1-XN could be increased by decreasing the growth pressure or the growth temperature, or by increasing TMIn/(TMIn+TMGa) input flow ratio or growth time. As a result, In-rich InXGa1-XN thin films that have x ratios in between 0.17 and 0.45 and exhibited single X-ray diffraction peak were grown. Comparing the elemental analysis of XPS with the XRD results, the two are consistent.
For AlInGaN thin film growth, we fixed the TMIn/(TMIn+TMGa) input flow ratio and increased TMAl input flow. The lattice constant became smaller when the TMAl input flow was increased.
Finally, we used AlInGAN as buffer layer to reduce lattice mismatch between In-rich InGaN and GaN. With 30 nm-thick AlInGaN buffer layer, the X-ray diffraction peak of the thin film shifted to left that indicated higher indium content. It was likely due to stress relaxation; In-rich InGaN was easier to grow. Moreover, using AlInGaN as a cladding material to grow multi-pair In0.43Ga0.57N/AlInGaN thin film structure, we found the X-ray diffraction profile was composed of two peaks with peak positions somewhat different from the original positions of In0.43Ga0.57N and AlInGaN. It was possibly resulted from lattice strain interaction and Al/Ga/In composition interdiffusion between layers during growth.

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