Fabrication of self-organized GaInNAs quantum dots by atomic H-assisted RF-molecular beam epitaxy

Abstract

Self-organized Ga x In 1− x N y As 1− y quantum dots (QDs) were fabricated on GaAs (0 0 1) substrates by atomic hydrogen-assisted molecular beam epitaxy with a radio frequency nitrogen plasma source (RF-MBE). By adjusting the amount of lattice mismatch between Ga x In 1− x N y As 1− y and GaAs to be almost the same as that of In 0.4Ga 0.6As and GaAs, we were able to fabricate Ga 0.53In 0.47N 0.02As 0.98 QDs with densities up to ∼1.1×10 11 cm −2 on GaAs (0 0 1) by atomic H-assisted RF-MBE. Further, we have studied the effect of atomic H irradiation on QDs’ growth dynamics and their optical properties. Based on the atomic force microscope and photoluminescence measurements, we found that there exists an optimum range of H 2 flow rates for a uniform and high quality Ga 0.53In 0.47N 0.02As 0.98 QDs formation on GaAs substrates.