Abstract
Effects of substrate misorientation and Zn doping characteristics on the device performance of AlGaInP double-heterostructure light-emitting diodes are described. The light output power is found to be strongly dependent on the Zn concentration. The degradation of light output, which was caused by the increase in the number of Zn atoms, is investigated by photoluminescence and electroluminescence measurements. The emission properties can be improved by optimizing the growth of AlGaInP on an intentionally misoriented substrate and the Zn-doping level in the p-cladding layer. The external quantum efficiency of 3.5% at 618 nm can be obtained from the optimized LEDs with a 7.5-μm-thick GaP window layer.