光致发光谱研究自组织InAs双模量子点态填充  

Photoluminescence Investigation of InAs Bimodal Self-Assembled Quantum Dots State Filling

作　　者：贾国治[1] 姚江宏[1] 张春玲[1] 舒强[1] 刘如彬[1] 叶小玲[2] 王占国[1,2] 

机构地区：[1]南开大学弱光非线性光子学材料先进技术及制备教育部重点实验室,天津市信息光子材料与技术重点实验室,南开大学泰达应用物理学院,天津300457 [2]中国科学院半导体研究所半导体材料科学重点实验室,北京100083

出　　处：《光谱学与光谱分析》2007年第11期2178-2181,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(60476042);天津市应用基础研究计划重点项目(06YFJZJC01100);长江学者创新团队发展计划资助

摘　　要：采用固态源分子束外延技术在GaAs(100)衬底上,制备了InAs量子点,对样品进行原子力显微镜测试,统计结果表明量子点尺寸呈双模分布。光致发光谱研究表明,在室温和77K下,小量子点的发光峰均占主导地位,原因可能是:(1)大量子点的态密度小于小量子点;(2)捕获载流子速率,大量子点小于小量子点;(3)大量子点与盖层存在较大的应变势垒和可能出现的位错和缺陷,导致温度变化引起载流子从小尺寸量子点转移到大尺寸的量子点中概率很小。Self-assembled InAs quantum dots were prepared on GaAs（100） substrate in a solid source molecular beam epitaxy system. The distribution and topographic images of uncapped dots were studied by atomic force microscope The statistical result shows that the quantum dots are bimodal distribution. The photoluminescence spectrum results shows that the intensity of small size quantum dots dominated, which may be due to. （1） the state density of large quantum dots lower than that of small quantum dots; （2） the carriers capture rate of large size quantum dots is small relative to that of small ones; （3） there is a large strain barrier between large quantum dots and capping layer, and the large strain is likely to produce the defect and dislocation, resulting in a probability of carriers transferring from large quantum dots to small dots that is very small with temperature increasing.

关 键 词：光致发光谱 量子点 双模分布 态填充 

分 类 号：O472.3[理学—半导体物理]