Numerical investigation on threading dislocation bending with InAs/GaAs quantum dots  

作　　者：Guo-Feng Wu Jun Wang Wei-Rong Chen Li-Na Zhu Yuan-Qing Yang Jia-Chen Li Chun-Yang Xiao Yong-Qing Huang Xiao-Min Ren Hai-Ming Ji Shuai Luo 武国峰;王俊;陈维荣;祝丽娜;杨苑青;李家琛;肖春阳;黄永清;任晓敏;季海铭;罗帅(State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Physics B》2021年第11期146-150,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.61874148,61974141,and 61674020);the Beijing Natural Science Foundation,China(Grant No.4192043);the National Key Research and Development Program of China(Grant No.2018YFB2200104);the Fund from the Beijing Municipal Science&Technology Commission,China(Grant No.Z191100004819012);the Project of the State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,China(Grant No.IPOC2018ZT01);the 111 Project of China(Grant No.B07005).

摘　　要：The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filters is a pretty good alternative to solving this problem.In this paper,a finite element method(FEM)is proposed to calculate the critical condition for InAs/GaAs QDs bending TDs into interfacial misfit dislocations(MDs).Making a comparison of elastic strain energy between the two isolated systems,a reasonable result is obtained.The effect of the cap layer thickness and the base width of QDs on TD bending are studied,and the results show that the bending area ratio of single QD(the bending area divided by the area of the QD base)is evidently affected by the two factors.Moreover,we present a method to evaluate the bending capability of single-layer QDs and multi-layer QDs.For the QD with 24-nm base width and 5-nm cap layer thickness,taking the QD density of 10^(11) cm^(-2) into account,the bending area ratio of single-layer QDs(the area of bending TD divided by the area of QD layer)is about 38.71%.With inserting five-layer InAs QDs,the TD density decreases by 91.35%.The results offer the guidelines for designing the QD dislocation filters and provide an important step towards realizing the photonic integration circuits on silicon.

关 键 词：InAs/GaAs quantum dots threading dislocation finite element method bending area 

分 类 号：O471.1[理学—半导体物理]