EFFECTS OF SUBSTRATE MISORIENTATION AND ZN DOPING CHARACTERISTICS ON THE PERFORMANCE OF ALGAINP VISIBLE LIGHT-EMITTING-DIODES

Effects of substrate misorientation and Zn doping characteristics on t he 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, wh ich was caused by the increase in the number of Zn atoms, is investiga ted by photoluminescence and electroluminescence measurements. The emi ssion properties can be improved by optimizing the growth of AlGaInP o n an intentionally misoriented substrate and the Zn-doping level in th e p-cladding layer. The external quantum efficiency of 3.5% at 618 nm can be obtained from the optimized LEDs with a 7.5-mum-thick GaP windo w layer.