MBE法制备GaAs/AlGaAs纳米线的微观量子结构的应力应变分布研究

Stress and Strain Analysis of the Quantum Structures within GaAs/AlGaAs Nanowires Grown by MBE

研究了砷化镓/砷化铝镓(GaAs/AlGaAs)核壳结构纳米线中量子结构的微结构和应力应变分布.本文使用分子束外延法制备了GaAs/AlGaAs纳米线,并使用高分辨技术和原子重构对纳米线中的量子结构进行了分类,通过几何相位分析,我们发现纳米线径向的应变主要来自于核与壳层的失配,量子结构主要影响纳米线轴向及扭转方向上的应变.同时量子点密度也影响着纳米线轴向方向的应变.

The microstructure and stress-strain distribution of quantum structures in GaAs/AlGaAs core-shell nanowires are studied.In this paper,GaAs/AlGaAs nanowires are fabricated by molecular beam epitaxy,and the quantum structures in nanowires were classified in two types by high-resolution transmission electron microscope and atomic reconstitution.After geometric phase analysis,we find that the mismatch between the core and the shell influences the radial strain of nanowires,while the quantum structures mainly affect the strain in the axial and torsional directions of the nanowires.The strain in the axial direction of the nanowires goes up with the density of quantum dots increasing.