中国物理B ›› 2006, Vol. 15 ›› Issue (6): 1315-1319.doi: 10.1088/1009-1963/15/6/030
周旺民1, 王崇愚2, 陈涌海3, 王占国3
Zhou Wang-Min (周旺民)ab, Wang Chong-Yu (王崇愚)bc, Chen Yong-Hai (陈涌海)d, Wang Zhan-Guo (王占国)d
摘要: In this paper, we perform systematic calculations of the stress and strain distributions in InAs/GaAs truncated pyramidal quantum dots (QDs) with different wetting layer (WL) thickness, using the finite element method (FEM). The stresses and strains are concentrated at the boundaries of the WL and QDs, are reduced gradually from the boundaries to the interior, and tend to a uniform state for the positions away from the boundaries. The maximal strain energy density occurs at the vicinity of the interface between the WL and the substrate. The stresses, strains and released strain energy are reduced gradually with increasing WL thickness. The above results show that a critical WL thickness may exist, and the stress and strain distributions can make the growth of QDs a growth of strained three-dimensional island when the WL thickness is above the critical value, and FEM can be applied to investigate such nanosystems, QDs, and the relevant results are supported by the experiments.
中图分类号: (Mechanical properties of nanoscale systems)