The growth, by low-pressure metal-organic vapor-phase epitaxy, of InGaAs/GaAs quantum dots emitting around 1.3μm, was studied by means of transmission electron microscopy and photoluminescence spectroscopy. By adjusting the encapsulating thickness of GaAs, which had been deposited onto the quantum dots before temperature-ramping from the low quantum-dot growth temperature to the higher barrier-growth temperature, desorption of the dislocated clusters which formed simultaneously with the optically active coherent quantum dots was possible. The extended defect-free quantum-dot array which was obtained by using this method exhibited an improved photoluminescence efficiency.

Metal-Organic Vapor-Phase Epitaxy of Defect-Free InGaAs/GaAs Quantum Dots Emitting around 1.3μm. G.Saint-Girons, G.Patriarche, L.Largeau, J.Coelho, A.Mereuta, J.M.Gérard, I.Sagnes: Journal of Crystal Growth, 2002, 235[1-4], 89-94