Mechanical Strain in Capped and Uncapped Self-Assembled Ge/Si Quantum Dots



Título del documento: Mechanical Strain in Capped and Uncapped Self-Assembled Ge/Si Quantum Dots
Revista: Brazilian journal of physics
Base de datos: PERIÓDICA
Número de sistema: 000389444
ISSN: 0103-9733
Autores: 1
1
2
Instituciones: 1Universidade Federal de Goias, Instituto de Ciencias Exatas e Tecnologicas, Jatai, Goias. Brasil
2Universidad de Pamplona, Departamento de Fisica y Geologia, Pamplona, Norte de Santander. Colombia
Año:
Periodo: Dic
Volumen: 45
Número: 6
Paginación: 615-620
País: Brasil
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Experimental, aplicado
Resumen en inglés In this study, we numerically calculate the spatial profile of mechanical strain on self-assembled germanium (Ge) quantum dots (QDs) grown on a silicon (Si) substrate. Although the topic has been exhaustively studied, interesting features have not been explained or even mentioned in the literature yet. We studied the effect of the cap layer considering two cases: capped QDs (where a Si cap is present above the Ge QDs) and uncapped QDs (where no Si is present above the Ge QDs). We observed that Ge in the capped QDs is more strained compared with the uncapped QDs. This expected effect is attributed to the additional tension from the Si cap layer. However, the situation is opposite for the Si substrate, it is more strained in the uncapped QD because the Ge layer is less strained in this case. We also calculated the band-edge alignment for the electrons and holes
Disciplinas: Física y astronomía
Palabras clave: Física de materia condensada,
Puntos cuánticos,
Esfuerzos mecánicos,
Perfil espacial
Keyword: Physics and astronomy,
Condensed matter physics,
Quantum dots,
Mechanical strain,
Spatial profile
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