Cathodoluminescence study of selective epitaxial growth of In Ga1−As (x∼0.53) thin quantum wells on InP pyramid structures on a masked substrate

Abstract

Abstract By means of scanning electron microscope (SEM) and cathodoluminescence (CL) measurements we have investigated selective epitaxial growth of lattice-matched InGaAs/InP single quantum wells (SQWs) buried in sidewalls of InP pyramid structures on a masked InP substrate. SQW and pyramid structures have been grown on SiO2-masked substrates, with 1 μm of circular openings, by using organometallic vapor-phase epitaxy. SEM/CL images have revealed that SQWs with thickness ranging from 2 to 14 ML are grown on (1 1 1)A sidewalls. No SQW structure is grown on (1 1 1)B sidewalls, which is due to the difference in growth rate between (1 1 1)A and (1 1 1)B planes. The observed results indicate that interfacet migration plays an important role in selective epitaxial growth of InGaAs SQW layers on InP pyramids. The spectral shape analysis of the observed CL spectra has suggested that the InGaAs SQW layers buried in the InP pyramids have the alloying effect with P to reduce a lattice mismatch with InP.