Richardson constant of Al- and Au-GaAs Schottky barrier diodes

The Richardson constant of Al- and Au-nGaAs Schottky barrier diodes of low doping concentration has been determined from the measured forward I-V characteristics. Richardson constants higher than the theoretical are related to the presence of an additional majority-carrier current caused by recombination of electrons at traps at the metal-semiconductor interface. The data shows that the traps are located approximately 0.75 eV below the conduction band and are in equilibrium with the metal.