Electroluminescence from Ge-Doped GaP p—n Junctions

Abstract

The electroluminescence from GaP containing Ge has been studied. p—n junctions were formed by the liquid epitaxy method. The peak of the dominant emission from these diodes is near 1.96 eV at 77°K. The maximum external quantum efficiency at 77°K was 8%. The emission appears to involve Zn and Ge pairs even though these impurities were doped on opposite sides of the junction. It was not possible to ascribe any emission lines to recombination involving Te and Ge. Current, voltage, and intensity dependences of the diodes have been measured. The results indicate that radiative recombination between Zn and Ge at 77°K is predominantly in the space-charge region. At low currents, photon-assisting tunneling becomes important.