Specific features of nanosize object formation in an InSb/InAs system by metal-organic vapor-phase epitaxy

Abstract

InSb quantum dashes (up to 4 × 109 cm−2) and quantum dots (QDs) (7 × 109 cm−2) were produced on InAs (100) substrates by the standard method of metal-organic vapor-phase epitaxy in the temperature range 420–440°C. A transformation of the shape and size of the quantum dashes is observed depending on the technological conditions of epitaxial deposition (quality of the matrix surface, growth temperature, flow rate, ratio between Group-V and -III elements in the gas phase, etc.). Control over the diffusion rate of reagents on the surface of the matrix based on an InAs epitaxial layer leads to a change in the transverse dimensions of the quantum dashes being deposited within the range 150–500 nm in length and 100–150 nm in width, respectively, with their height remaining at 50 nm. InSb QDs are grown on the surface of the InAs substrate at T = 440°C. A bimodal size distribution of the nano-objects is observed: there are small (average height 15 nm; average diameter 60 nm) and large (average height 25 nm; average diameter 110 nm) QDs.