MBE growth strategy and optimization of GaAsBi quantum well light emitting structure beyond 1.2 μm

摘要

GaAs1-xBix/AlGaAs quantum wells (QWs) with varying As/Ga beam equivalent pressure (BEP) ratios were grown by solid source molecular beam epitaxy at a relatively high temperature of 350-400 degrees C intended for light emitting applications with wavelengths beyond 1.2 mu m. Both the Bi content and the photoluminescence (PL) intensity were found to be highly dependent on As-2 flux, especially for the case of growing GaAsBi at a relatively high temperature. A graded index separate confinement GaAsBi/AlGaAs single QW with 5.8% Bi exhibited a strong PL emission at 1.22 mu m. The growth strategy to incorporate considerable Bi into GaAs at a relatively high temperature through meticulous control of the As/Ga BEP ratio and compensation of Bi flux is demonstrated to be effective in guaranteeing a high Bi content as well as an optimal optical performance of GaAsBi QWs. Published under license by AIP Publishing.