摘要
Single and dual layers of InGaN quantum dots(QDs)are grown by metal organic chemical vapor deposition.In the former,the density,average height and diameter of QDs are 1.3×10^(9) cm^(−2),0.93 nm and 65.1 nm,respectively.The latter is grown under the same conditions and possesses a 20 nm low-temperature grown GaN barrier between two layers.The density,average height and diameter of QDs in the upper layer are 2.6×10^(10) cm^(−2),4.6 nm and 81.3 nm,respectively.Two reasons are proposed to explain the QD density increase in the upper layer.First,the strain accumulation in the upper layer is higher,leading to a stronger three-dimensional growth.Second,the GaN barrier beneath the upper layer is so rough it induces growth QDs.
作者
吕文彬
汪莱
王嘉星
郝智彪
罗毅
LV Wen-Bin;WANG Lai;WANG Jia-Xing;HAO Zhi-Biao;LUO Yi(State Key Laboratory on Integrated Optoelectronics/Tsinghua National Laboratory for Information Science and Technology,Department of Electronic Engineering,Tsinghua University,Beijing 100084)
基金
Supported by the National Basic Research Program of China under Grant Nos 2011CB301902,and 2011CB301903
the National High-Technology Research and Development Program of China under Grant Nos 2011AA03A112,2011AA03A106 and 2011AA03A105
the National Natural Science Foundation of China under Grant Nos 60723002,50706022,60977022 and 51002085
Beijing Natural Science Foundation under Grant No 4091001.