Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate

Antonio D. Utrilla, Davide F. Grossi, Daniel F. Reyes, Alicia Gonzalo, Verónica Braza, Teresa Ben, David González, Alvaro Guzman, Adrian Hierro, Paul M. Koenraad, Jose M. Ulloa

Research output: Contribution to journalArticleAcademicpeer-review

3 Citations (Scopus)

Abstract

The practical realization of epitaxial quantum dot (QD) nanocrystals led before long to impressive experimental advances in optoelectronic devices, as well as to the emergence of new technological fields. However, the necessary capping process is well-known to hinder a precise control of the QD morphology and therefore of the possible electronic structure required for certain applications. A straightforward approach is shown to tune the structural and optical properties of InAs/GaAs QDs without the need for any capping material different from GaAs or annealing process. The mere adjust of the capping rate allows controlling kinetically the QD dissolution process induced by the surface In-Ga intermixing taking place during overgrowth, determining the final metastable structure. While low capping rates make QDs evolve into more thermodynamically favorable quantum ring structures, increasing capping rates help preserve the QD height and shape, simultaneously improving the luminescence properties. Indeed, a linear relationship between capping rate and QD height is found, resulting in a complete preservation of the original QD geometry for rates above ∼2.0 ML s−1. In addition, the inhibition of In diffusion from the QDs top to the areas in between them yields thinner WLs, what could improve the performance of several QD-based optoelectronic devices.

LanguageEnglish
Pages260-266
Number of pages7
JournalApplied Surface Science
Volume444
DOIs
StatePublished - 30 Jun 2018

Fingerprint

Semiconductor quantum dots
Nanostructures
Optoelectronic devices
gallium arsenide
indium arsenide
Nanocrystals
Electronic structure
Luminescence
Structural properties
Dissolution
Optical properties
Annealing
Geometry

Keywords

  • Capping rate
  • Dissolution process
  • Molecular beam epitaxy
  • Quantum dot
  • Quantum ring
  • Wetting layer

Cite this

Utrilla, A. D., Grossi, D. F., Reyes, D. F., Gonzalo, A., Braza, V., Ben, T., ... Ulloa, J. M. (2018). Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate. Applied Surface Science, 444, 260-266. DOI: 10.1016/j.apsusc.2018.03.098
Utrilla, Antonio D. ; Grossi, Davide F. ; Reyes, Daniel F. ; Gonzalo, Alicia ; Braza, Verónica ; Ben, Teresa ; González, David ; Guzman, Alvaro ; Hierro, Adrian ; Koenraad, Paul M. ; Ulloa, Jose M./ Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate. In: Applied Surface Science. 2018 ; Vol. 444. pp. 260-266
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Utrilla, AD, Grossi, DF, Reyes, DF, Gonzalo, A, Braza, V, Ben, T, González, D, Guzman, A, Hierro, A, Koenraad, PM & Ulloa, JM 2018, 'Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate' Applied Surface Science, vol. 444, pp. 260-266. DOI: 10.1016/j.apsusc.2018.03.098

Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate. / Utrilla, Antonio D.; Grossi, Davide F.; Reyes, Daniel F.; Gonzalo, Alicia; Braza, Verónica; Ben, Teresa; González, David; Guzman, Alvaro; Hierro, Adrian; Koenraad, Paul M.; Ulloa, Jose M.

In: Applied Surface Science, Vol. 444, 30.06.2018, p. 260-266.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate

AU - Utrilla,Antonio D.

AU - Grossi,Davide F.

AU - Reyes,Daniel F.

AU - Gonzalo,Alicia

AU - Braza,Verónica

AU - Ben,Teresa

AU - González,David

AU - Guzman,Alvaro

AU - Hierro,Adrian

AU - Koenraad,Paul M.

AU - Ulloa,Jose M.

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Y1 - 2018/6/30

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KW - Capping rate

KW - Dissolution process

KW - Molecular beam epitaxy

KW - Quantum dot

KW - Quantum ring

KW - Wetting layer

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DO - 10.1016/j.apsusc.2018.03.098

M3 - Article

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JO - Applied Surface Science

T2 - Applied Surface Science

JF - Applied Surface Science

SN - 0169-4332

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Utrilla AD, Grossi DF, Reyes DF, Gonzalo A, Braza V, Ben T et al. Size and shape tunability of self-assembled InAs/GaAs nanostructures through the capping rate. Applied Surface Science. 2018 Jun 30;444:260-266. Available from, DOI: 10.1016/j.apsusc.2018.03.098