奈米鑽石薄膜成長於氮化鎵基板之製程及結構分析

Processings and characterizations of nanocrystalline diamond on GaN substrate

江珮甄(Chiang, Pei Chen)

指導教授 ： 戴念華

國立清華大學/工學院/材料科學工程學系/碩士(2015年)

摘要

本研究以管爐製備氮化鎵薄膜，討論其成長溫度和通入氨氣的流量對成長氮化鎵的影響，找出成長氮化鎵薄膜的最佳條件；再使用微波輔助化學氣相沉積法成長鑽石薄膜於氮化鎵基板上，希望透過鑽石薄膜的良好熱傳導性質來改善傳統的發光二極體在氧化鋁上的散熱性質。成長鑽石薄膜的種類包括單層的超奈米晶鑽石薄膜 (Ultranano crystalline diamond, UNCD)及雙層複合膜，雙層複合膜是由兩層不同大小的鑽石晶粒所組合而成，利用掃描式電子顯微鏡(Scanning electron microscope, SEM)觀察其表面形貌及穿透式電子顯微鏡(Transmission electron microscopy, TEM)觀察微結構；再以X光繞射儀確認晶體結構，並利用拉曼光譜儀確定薄膜的性質。 研究結果顯示，以管爐成長氮化鎵的最佳條件在850 ℃下通入30 sccm氨氣成長三小時，在此條件下成長的薄膜具有帄滑的表面有利於成長鑽石薄膜。在氮化鎵的基板上成長鑽石薄膜並不容易，因此我們利用超音波震盪成核增加成核密度，並利用電漿化學氣相沉積法成長UNCD。在雙層膜部分以成長UNCD作為底層，可以成功成長奈米晶鑽石(Nanocrystalline diamond, NCD)/ UNCD雙層膜在氮化鎵薄膜上面，最後以SEM、TEM和拉曼光譜儀分析本實驗製備的薄膜特性。

關鍵字

奈米鑽石 ； 氮化鎵 ； 結構分析

並列摘要

In this study, we grow GaN film and investigated the influence of growing temperature and the flow rate of ammonia gas on the quality of the synthesized GaN thin film. Subsequently, we used the microwave plasma enhanced chemical vapor deposition to grow diamond film on GaN substrate. The objective of this study is to improve the thermal dissipation of a GaN substrate used in light emitting diode. In this regard, we fabricated the single and hybrid granular structured diamond films on GaN substrate. The hybrid diamond films are composed of diamond films with different grain size. We examined the morphology of the films by scanning electron microscope (SEM) and transmission electron microscope (TEM). The crystal structures of the samples were analyzed by X-ray diffractometer, and the bonding properties were characterized by Raman Spectroscopy. The results showed that the optimal conditions for growing GaN thin film is at 850 ℃ with 30 sccm ammonia gas flow. The film growth under these conditions has a smooth surface which is facilitate the growth of diamond films. For hybrid diamond film, we grow ultranano crystalline diamond (UNCD) as a bottom layer followed by grown nano crystalline diamond(NCD)/ UNCD hybrid structured diamond film. The properties of the as-synthesized NCD/UNCD hybrid diamond film were characterized by SEM, TEM and Raman.

並列關鍵字

nanocrystalline diamond ； GaN ； characterization

參考文獻

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