High-Efficiency InGaN/GaN Dot-in-a-Wire Red Light-Emitting Diodes

We report on the achievement of high-performance InGaN/GaN dot-in-a-wire red light-emitting diodes on Si(111) substrates. Owing to the superior 3-D carrier confinement offered by the self-organized dot-in-a-wire heterostructures, the devices exhibit relatively high (~18%-32%) internal quantum efficiency at room temperature. Moreover, no efficiency droop was observed for injection current up to ~480A/cm² under pulsed biasing conditions. We have also demonstrated that, by controlling the inhomogeneous broadening of the dot-in-a-wire heterostructures, the devices can exhibit relatively stable emission characteristics with increasing current.