InAs self-organized quantum dots grown by molecular beam epitaxy using a "nucleation-augmented" method

Abstract

Photoluminescence (PL) measurements performed in a series of InAs self-assembled quantum dot (QD) structures grown by molecular beam epitaxy (MBE) on GaAs (100) substrates using a two-stage "nucleation-augmented" growth method show that an InAs QD "nucleation" layer grown at a fast growth rate, followed by a slowly grown InAs "augmented" layer, dramatically increases the dot density and improves the PL intensity. Besides red-shift in peak wavelength, the PL intensity was found to increase as the growth rate of the InAs augmented layer was reduced. The increased PL intensity was due to a higher dot density arising from the nucleation layer and an improved optical quality caused by the growth interruption in the augmented layer. © World Scientific Publishing Company.