MOCVD growth and characterization of multi-stacked InAs/GaAs quantum dots on misoriented Si(100) emitting near 1.3 μm

Abstract

We report near 1.3μm strong photoluminescence (PL) emission from 5-stacked InAs/GaAs quantum dots (QDs) monolithically grown on Si (1 0 0) substrates with 4° miscut towards [110] direction by metal organic chemical vapor deposition (MOCVD). The metamorphic QD samples on Si were grown by three-step method, in which bottom Al0.8Ga0.2As cladding and GaAs waveguide layers were simultaneously incorporated in order to fabricate Si-based QD light emitting devices later. In particular, the GaAs waveguide layer grown with low and high temperature alternated significantly suppresses the upwards propagating of threading dislocations (TDs) into QD region and flattens the surface for latter adjacent nucleation of QDs. As a result, room-temperature photoluminescence intensity of as-grown Si-based InAs/GaAs QD sample attains 87% of that on GaAs and its PL peak as long as 1280nm with the full width at half maximum value up to 78nm (i.e., 60meV). Our study shows the great opportunity of using MOCVD grown Si-based metamorphic QDs for 1.3μm band light emitting devices.