六方相InGaN外延膜的显微Raman散射  

Micro-Raman scattering study of hexagonal InGaN epitaxial layer

作　　者：王瑞敏[1] 陈光德[1] 竹有章[1] 

机构地区：[1]西安交通大学理学院,西安710049

出　　处：《物理学报》2006年第2期914-919,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10474078);陕西省自然科学基金(批准号:2004A01)资助的课题~~

摘　　要：用X射线衍射(XRD)技术和显微Raman散射方法对金属有机化学气相沉积(MOCVD)法生长的六方相In_xGa_(1-x)N薄膜样品进行了研究,观察到了相分离现象和LO声子-等离子耦合模(LPP+),讨论了In_xGa_(1-x)N的A1(LO)模被屏蔽的主要物理机制.同时,对Raman谱中E2和A1(TO)声子模进行了分析和讨论.在In_xGa_(1-x)N样品的低温Raman谱中还观察到单电子跃迁产生的Raman散射信号.Hexagonal InxGa1-xN film grown by metalorganic chemical vapor deposition （MOCVD） was studied by Micro-Raman scattering and X-ray diffraction. The phase separation was observed in InxGa1-xN, the biaxial stress was measured by both Raman and X-ray diffraction. In Raman spectroscopy, the A1 （LO） mode of InxGa1-xN is absent. Instead, the LO phonon- plasmon coupled mode （LPP＋ ） was observed at about 778 cm^-1. The carrier concentration was determined by the frequency of the coupled mode. The E2 and A1 （TO）modes of InxGa1-xN layer exhibit a down-shift compare to those of GaN layer. At low temperature, the peak induced by electronic transition was observed in Raman spectra of InxGa1-xN.

关 键 词：RAMAN散射 X射线衍射 相分离 应力 LO声子-等离子耦合 

分 类 号：O484.41[理学—固体物理]