Correlation between photoluminescent and electroluminescent efficiency in gallium phosphide

The most important device parameter of an electroluminescent diode is the external quantum efficiency. This in turn is influenced by the properties of the junction (injection efficiency), by the recombination processes in the bulk material (recombination efficiency), and by the optical properties of the semiconductor (optical efficiency). This paper shows how the three effects can be separated by measuring photoluminescent efficiencies in various dielectric media along with electroluminescent efficiencies and Hall parameters. The external electroluminescent quantum efficiency of the diode can be predicted from measurements on the annealed wafers on the basis of the above information.