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Determination of atomic vacancies in InAs/GaSb strained-layer superlattices by atomic strain.

ABSTRACT: Determining vacancy in complex crystals or nanostructures represents an outstanding crystallographic problem that has a large impact on technology, especially for semiconductors, where vacancies introduce defect levels and modify the electronic structure. However, vacancy is hard to locate and its structure is difficult to probe experimentally. Reported here are atomic vacancies in the InAs/GaSb strained-layer superlattice (SLS) determined by atomic-resolution strain mapping at picometre precision. It is shown that cation and anion vacancies in the InAs/GaSb SLS give rise to local lattice relaxations, especially the nearest atoms, which can be detected using a statistical method and confirmed by simulation. The ability to map vacancy defect-induced strain and identify its location represents significant progress in the study of vacancy defects in compound semiconductors.

SUBMITTER: Kim H

PROVIDER: S-EPMC5755578 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Determination of atomic vacancies in InAs/GaSb strained-layer superlattices by atomic strain.

Kim Honggyu H Meng Yifei Y Kwon Ji-Hwan JH Rouviére Jean-Luc JL Zuo Jian Min JM

IUCrJ 20180101 Pt 1

Determining vacancy in complex crystals or nanostructures represents an outstanding crystallographic problem that has a large impact on technology, especially for semiconductors, where vacancies introduce defect levels and modify the electronic structure. However, vacancy is hard to locate and its structure is difficult to probe experimentally. Reported here are atomic vacancies in the InAs/GaSb strained-layer superlattice (SLS) determined by atomic-resolution strain mapping at picometre precisi ...[more]

PMID: 29354272

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