Electroluminescence in GAAS by Tunnel Injection of Minority Carriers

摘要

Experiments have been carried out to observe the recombination radiation which results from the tunnel-injection of minority carriers into a degenerately doped single crystal of Gallium Arsenide. Electroluminescence was observed in the 1.49 eV spectral region at 4 degrees K and 77 degrees K. A theoretical model was proposed to explain the observed luminescence which involved the assumption that holes tunnel into the GaAs valence band through a barrier of magnitude Psi sub h, and that electrons simultaneously tunnel out of the GaAs conduction band through another barrier of magnitude Psi sub e. Using the Bethe-Sommerfeld tunneling model, but neglecting the image force term, the effective magnitudes of Psi sub e and Psi sub h were determined by fitting the theoretical hole and electron tunneling expressions to similar expressions constructed from the observed data. In order to explain the data it was found necessary to modify the original model to include the effect of pinholes in the insulating film. When so modified the theory adequately explains the luminescence and I(V) behavior of the MIS wafer. (Author)