Growth rate effects on the size, composition and optical properties of InAs/GaAs quantum dots grown by molecular beam epitaxy

• Published in: Journal of crystal growth Vol. 227; pp. 1000 - 1004
• Main Authors: Joyce, P.B, Krzyzewski, T.J, Bell, G.R, Jones, T.S, Malik, S, Childs, D, Murray, R
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-07-2001
• Subjects: A1. Surface processes; A1. Surfaces; A3. Molecular beam epitaxy; B1. Arsenates; B2. Semiconducting III–V materials; A1. Surface processes; A3. Molecular beam epitaxy; B2. Semiconducting III–V materials; B1. Arsenates; A1. Surfaces
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(01)00967-8

The effect of the InAs deposition rate on the properties of InAs/GaAs quantum dots (QDs) grown on GaAs (0
0
1) substrates by molecular beam epitaxy has been studied by scanning tunnelling microscopy (STM) and photoluminescence (PL). PL studies performed on GaAs capped QD samples show that the emission wavelength increases with decreasing growth rate, reaching a maximum around 1.3
μm, with the linewidth decreasing from 44 to 27
meV. STM studies on uncapped dots show that the number density, total QD volume and size fluctuation all decrease significantly as the growth rate is reduced. The observed shifts in the emission wavelength and linewidth are attributed to changes in the QD size, size distribution and composition.