AlGaInP orange light-emitting diodes grown on misoriented p-GaAs substrates

Abstract

AlGaInP double-heterostructure light-emitting diodes (LEDs) grown on misoriented p-GaAs substrates cut 15°-off the (100) plane toward the [011] direction have been fabricated. The device performance was found to be strongly dependent on the doping levels in both cladding layers. The light output first increases up to 39 mcd and then decreases with further increases in the Si-doping level. However, for the lower cladding layer with high doping levels, the decay of light output is caused by an increase of nonradiative recombination due to the Zn diffusion into the active layer. When prepared by the optimum doping concentrations, the external quantum efficiency at 20 mA is 0.6%, corresponding to a luminous intensity of 39 mcd at 615 nm orange light for the AlGaInP bare chips.