In_(0.2)Ga_(0.8)As-GaAs复合应力缓冲层上的1.3μm InAs/GaAs自组织量子点  

1.3μm InAs/GaAs SELF-ASSEMBLED QUANTUM DOTS GROWN ON In_(0.2)Ga_(0.8)As-GaAs COMBINED STRAIN-BUFFER LAYER

作　　者：方志丹[1] 龚政[2] 苗振华[2] 牛智川[2] 沈光地[1] 

机构地区：[1]北京工业大学光电子技术实验室,北京100022 [2]中国科学院半导体研究所半导体超晶格国家重点实验室,北京100083

出　　处：《红外与毫米波学报》2005年第5期324-327,共4页Journal of Infrared and Millimeter Waves

基　　金：国家高技术研究发展技术资助的课题(2002AA302107)

摘　　要：用光荧光谱和原子力显微镜测试技术系统研究了在2 nm In0.2Ga0.8As和xML GaAs的复合应力缓冲层上生长的InAs/GaAs自组织量子点的发光特性和表面形貌.采用In0.2Ga0.8As与薄层GaAs复合的应力缓冲层,由于减少了晶格失配度致使量子点密度从约1.7×109cm-2显著增加到约3.8×109cm-2.同时,复合层也有利于提高量子点中In的组份,使量子点的高宽比增加,促进量子点发光峰红移.对于x=10 ML的样品室温下基态发光峰达到1350 nm.Optical properties and surface structures of InAs/GaAs serf-assembled quantum dots （QDs） grown on 2 nm In0.2Ga0.8As and x ME GaAs combined strain-buffer layer were investigated systematically by photoluminescence （PL） and atomic force microscopy （AFM）. The QD density increased from - 1.7 × 10^9 cm^-2 to - 3. 8 × 10^9 cm^-2 due to the decreasing of the lattice mismatch. The combined layer was of benefit to increasing In incorporated into dots and the average height-to-width ratios, which resulted in the red-shift of the emission peaks. For the sample ofx = 10 ML, the ground state transition is shifted to 1350 nm at room temperature.

关 键 词：INAS/GAAS量子点 复合应力缓冲层 光荧光 原子力显微镜 

分 类 号：O482.3[理学—固体物理]