MOCVD growth, stimulated emission and time-resolved PL studies of InGaN/(In)GaN MQWs: well and barrier thickness dependence

Optically pumped stimulated emission (SE) and time-resolved photoluminescence (TRPL) of InGaN/(In)GaN multiple quantum wells (MQWs) grown by low-pressure metalorganic chemical vapor deposition (MOCVD) were systemically studied as a function of well and barrier thickness. The SE threshold pumping density and photoluminescence (PL) decay time were found to be strongly dependent on the well and barrier thickness. As the barrier thickness increases, the PL efficiencies and room temperature PL decay time significantly increase, which can be attributed to the improved structural quality, as seen by the reciprocal lattice mapping results. The lowest SE threshold density of 58kW/cm2 was obtained for the 3.0nm well and 15.0nm barrier sample. The experimental results indicate that the enhanced optical quality of samples with larger barrier thicknesses can be readily applied to the fabrication of InGaN/(In)GaN LDs.