Photoluminescence Studies of overgrown GaAs/AlGaAs MOCVD and MBE Quantum Dots..

Abstract

A comparison of the photoluminescence emission from MOCVD overgrown quantum dots (QDs) patterned in MOCVD and MBE grown starting material has been made. Before overgrowth luminescence was obtained from the QDs down to 750Å in diameter fabricated in MBE material whereas after overgrowth only the larger 3000Å QDs luminesce. However when MOCVD material is used the largest dots (3500Å) only luminesce after regrowth. With both types of material the QW emission shifts to higher energies after regrowth.