Enhanced photoluminescence of InAs self-assembled quantum dots grown by molecular-beam epitaxy using a 'nucleation-augmented' method

Journal Article · Mon Jul 26 04:00:00 EDT 2004 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1773914· OSTI ID:20632688

Chia, C K; Chua, S J; Miao, Z L; Chye, Y H ^[1]

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1. Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602 (Singapore)

A two-stage 'nucleation-augmented' growth method for producing InAs self-assembled quantum dots (QDs) using molecular-beam epitaxy on GaAs (100) substrates has been investigated in detail. Photoluminescence (PL) measurements show that a 1.8-monolayer-(MLs) InAs QD 'nucleation' layer grown at a fast rate, followed by a 2.6-MLs-InAs 'augmented' layer grown under pulsed conditions at a slow rate, dramatically increases the dot density and improves the PL intensity for the InAs QDs. It was found that, when the effective growth rate of the InAs augmented layer was reduced, the PL peak emission shifts to a longer wavelength and the PL intensity is enhanced. These changes in characteristics were attributed to improved optical quality and greater dot density.

• OSTI ID: 20632688
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 4 Vol. 85; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GALLIUM ARSENIDES
INDIUM ARSENIDES
LAYERS
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
SPECTRAL SHIFT
SUBSTRATES