SiC衬底AlN缓冲层的应变对GaN外延层质量的影响  

Effect of the Strain of AlN Buffer Layer on the Quality Evolution of GaN Epilayer Grown on SiC Substrate

作　　者：王丽 房玉龙[2] 尹甲运[2] 敦少博[2] 刘波[2] 冯志红[2] 

机构地区：[1]科技信息中心,北京100044 [2]专用集成电路重点实验室,石家庄050051

出　　处：《半导体技术》2012年第8期630-633,共4页Semiconductor Technology

基　　金：国家自然科学基金重大项目(60890192;60876009)

摘　　要：在3英寸(1英寸=2.54 cm)SiC衬底上采用金属有机物化学气相沉积(MOCVD)法生长GaN外延材料。研究了AlN缓冲层的应变状态对GaN外延层应变状态和质量的影响。使用原子力显微镜和高分辨率X射线双晶衍射仪观察样品表面形貌,表征外延材料质量的变化,使用高分辨喇曼光谱仪观察外延材料应力的变化,提出了基于外延生长的应变变化模型。实验表明,GaN外延层的张应变随着AlN缓冲层应变状态的由压变张逐渐减小,随着GaN张应力的逐渐减小,GaN位错密度也大大减少,表面形貌也逐渐变好。The GaN epilayer was grown by the metal-organic chemical vapor deposition on 3-inch SiC substrate.The influence of the strain of AlN buffer layer on the quality evolution and quality of GaN epilayer were studied by the atomic force microscopy,high-resolution X-ray diffractometry and Raman scattering.A model based on the strain evolution during the epitaxial growth is put forward.The results show that the tensile strain of the GaN layers decreases with the increment of the compressive strain of the AlN buffers.With the decrement of the tensile stress of the GaN layer,the thread dislocation density decreases and the surface morphology gets better.

关 键 词：金属有机物化学气相沉积(MOCVD) GAN外延层 ALN缓冲层 失配 应变 应力 

分 类 号：TN304.2[电子电信—物理电子学]