Internal Quantum Efficiency of GaAs Electroluminescent Diodes

Abstract

The internal quantum efficiency and spectral distribution of radiation from GaAs electroluminescent diodes is examined with a careful investigation of the optical absorption of both the n‐type and p‐type layers of the diodes. A group of diodes so fabricated as to allow necessary corrections for internal absorption and reflection has internal quantum efficiencies greater than 50%. These diodes have more than 85% of all photons in the principal peak and the temperature variation of the emission is explainable on the basis of changes of the absorption with temperature. In addition, the shape of the emission can be interpreted in terms of radiation originating in a compensated p‐type layer of relatively low carrier concentration.