InAs Quantum Dot Growth on a Thin GaNP Buffer Layer on GaP by Metalorganic Chemical Vapor Deposition

Abstract

InAs quantum dots (QDs) on a 2-nm-thick GaNP buffer layer on GaP were investigated using low-pressure metalorganic chemical vapor deposition. The InAs QDs density was significantly increased from 2.6×109 to 2.0×1010 cm-2 by increasing the nitrogen composition from 0 to 4.5% in GaNP. The formation characteristics of InAs QDs were also investigated at various InAs supply amounts from 0.7 to 2.5 monolayers (ML). The generation of QDs on the GaNP and GaP buffer layers started at the InAs supplies of 1.0 and 1.1 ML, respectively. Since the lattice mismatches were large, these supply amounts were definitely smaller than that on GaAs.