Enhanced 1.3 µm luminescence from InGaAs self-assembled quantum dots with a GaAsN strain-compensating layer

We have studied room temperature (RT) photoluminescence (PL) emission and strain characteristics of InGaAs quantum dots (QDs) grown on GaAs using metal organic vapor phase epitaxy. The InGaAs QDs were covered by a 10 nm thick GaAsN layer having a nitrogen composition of either 0.3% or 0.9% and a following 50 nm thick GaAs layer. The RT-PL emission intensity of InGaAs QDs has been increased with reduced linewidth for 1.3 µm device application by using GaAsN strain-compensating layers. The Raman spectra of InGaAs QDs covered by GaAsN0.009 show the InGaAs QD phonon frequency shift toward that of InGaAs surface QDs, which gives clear evidence for strain compensation.