Atomic Pathways of Solute Segregation in the Vicinity of Nanoscale Defects.
Nano Lett
; 21(23): 9882-9888, 2021 Dec 08.
Article
em En
| MEDLINE
| ID: mdl-34797681
ABSTRACT
Using GeSn semiconductor as a model system, this work unravels the atomic-level details of the behavior of solutes in the vicinity of a dislocation prior to surface segregation in strained, metastable thin layers. The dislocations appear in the 3D atom probe tomography maps as columnar regions, 3.5-4.0 nm wide, with solute concentrations 3-4 times higher than the sounding matrix. During the initial stage of phase separation, the migration of solute atoms toward the dislocation is associated with a gradual increase in Sn concentration and in density of atomic clusters, which reach 175-190 per 103 nm3 with 12-15 atoms/cluster close to dislocations. The latter provide, at advanced stages, fast diffusive channels for Sn mass-transport to the surface, thus bringing the matrix around the dislocation to the equilibrium concentration. In parallel, an increase in solute concentration (â¼0.05 at. %/nm) and in the number of atomic clusters (12-16 clusters/33 nm) is observed along the dislocation core.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Nano Lett
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Canadá
País de publicação:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA