Molecular beam epitaxy growth of GaAsBi/GaAs/AIGaAs separate confinement heterostructures

摘要

GaAsBi/GaAs/AIGaAs separate confinement heterostructures are grown using an asymmetric temperature profile due to the low optimal growth temperature of GaAsBi; the bottom AlGaAs barrier is grown at 610 ℃, while the GaAsBi quantum well and the top AlGaAs barrier are grown at 320 ℃. Cross-sectional transmission electron microscopy and room temperature photoluminescence measurements indicate that this approach results in samples with excellent structural and optical properties. The high quality of the low temperature AlGaAs barrier is attributed to the presence of Bi on the surface as indicated by a (1 × 3) surface reconstruction persisting throughout the low temperature growth.