THE METHODS FOR INCREASING THE EFFICIENCY AND RELIABILITY OF EMITTING DIODES BASED ON GaInAsP

Abstract

The quantum production of the electroluminescence of semiconductor emitters of the optical range is determined by the parameters of several stages of the process of converting electrical energy into optical radiation energy. To improve the efficiency and stability of the emitting diodes, the losses at certain stages of this process were investigated. When obtaining information on the distribution of impurities in p–n junctions of light-emitting diodes, volt-farad characteristics were measured. In the studied radiators, a linear impurity distribution in the p – n junction was obtained. The electrical and electroluminescent characteristics of emitting diodes based on GaInAsP were studied. The elucidation of the mechanism of diode degradation during their current training for 3000 hours at different current densities and temperatures, on the radiation intensity, that measured at low and high injection levels, on the value of the photocurrent p-n-junction and on their electrical characteristics was carried. It is shown that the degradation of the studied radiators is due to the change in the ratio between the radiative and non-radiative components of the current in p-n-junctions, as well as the change in the electron lifetime in the active region of the heterostructures. The kinetics of degradation of diodes is explained by the drift of charged defects in an electric field. It was found that a decrease in the quantum efficiency of GaInAsP-based diodes with a decrease in the injection level is due to the presence of local narrowing of p-n-junctions. It is shown that in order to reduce degradation of emitting diodes and to increase their quantum efficiency at low injection levels, it is necessary to reduce the concentration of residual impurities and lattice defects in the used semiconductor heterostructures.