Effects of growth pause on the structural and optical properties of InGaAsN–InGaAsP quantum well

Abstract

Optical and structural characterizations were conducted on an InGaAsN quantum well (QW) with large energy bandgap barrier material consisting of InGaAsP ( E g=1.62 eV) grown by metalorganic chemical vapor deposition. A growth pause annealing technique substantially improves both the structural and the optical quality of the QW. With an optimum growth pause of 14 s, surface roughness reduces by 50% and photoluminescence intensity increases 25 times compared with the sample undergoing a 3-s growth pause. No significant emission wavelength blue shift was observed, indicating this growth pause annealing process involves a mechanism different from that of the conventional post-growth thermal annealing of InGaAsN QW. Preliminary results on InGaAsN-active diode lasers employing InGaAsP barrier material indicate performance is limited by nonradiative recombination.