利用分子束磊晶系統成長氮化鎵在多種基板上

Abstract

本研究利用電漿輔助式分子束磊晶系統在不同的基板上，矽(111)、藍寶石(0001)以及4H碳化矽基板上成長氮化鎵異質結構的薄膜材料，我們分成以下四個系列來作探討。 1.不同基板之氮化鎵樣品成長之觀察 2.不同基板氮化鎵經熱退火後之觀察 3.不同鎵流量之氮化鎵在4H-碳化矽基板上成長之觀察 4.不同基板成長溫度下氮化鎵在4H-碳化矽基板上成長之材料成長特性 我們透過反射高能量電子繞射以及場發射掃描式電子顯微鏡觀察氮化鎵薄膜表面不同的形貌，此外，透過高解析繞射X光繞射可以知道薄膜磊晶的品質，材料殘留應力以及發光特性可以由光激發螢光光譜得知。至於X射線光電子能譜則可以幫助我們得知其薄膜內部組成狀態與原子的鍵結。 除了實驗的分析以及觀察之外，我們也提出氮化鎵薄膜經過熱退火後之成長機制，以及改變基板成長溫度與鎵流量對於氮化鎵在4H-碳化矽基板上成長之相關成長機制。

In this thesis, the heterostructure GaN materials were grown on various substrates, Si(111),Sapphire(0001),and 4H-SiC, by PA-MBE.We devide into four parts to discusss. (a) Growth GaN on different substrates (b) Growth GaN on different substrates with annealing (c) Growth GaN on 4H-SiC with different Ga flux (d) Growth GaN on 4H-SiC at different temperature We can observe surface morphology of GaN films by reflection high energy electron diffraction (RHEED) and field emission scanning electron microscopy(FESEM). The crystal quality of GaN films can be analysed by high resolution X-Ray diffraction (HR-XRD). Photoluminescence spectroscopy (PL) also shows the stress and optical properties of GaN films. In addition, surface composition and atomic-bonds are studied by X-ray photoelectron spectroscopy. Finally, we also discuss the growth of GaN films with annealing. We also discuss the growth of GaN films on 4H-SiC substrates in different Ga flux and substrate temperatures.