InAs/GaAs self-organized quantum dots on (411)A GaAs by molecular beam epitaxy

Self-organized InAs QDs formation on (4 1 1)A GaAs and on controlled (1 0 0) GnAs substrates were studied by in-situ RHEED observation, AFM measurement and PL spectroscopy. The transition from two-dimensional to three-dimensional growth on (4 1 1)A was observed by RHEED pattern transformation to indicate the critical layer thickness of InAs QDs formation. The result is almost the same as that on (1 0 0). Improvement of QDs alignment having dot size uniformity on (4 1 1)A, was observed by AFM measurement. Enhanced optical properties of QDs on (4 1 1)A was shown by low-temperature PL spectroscopy. Strong PL peak at 966 nm having FWHM of 35 nm was obtained from the 3-stacked QDs on (4 1 1)A. The narrower PL FWHM of QDs peak. on (4 1 1)A comes from the improved uniformity of QDs on (411)A. (C) 2001 Elsevier Science B.V. All rights reserved.