Nonlinearity in the theory of hot electrons due to excess of charge carriers in the presenceof electric field

Abstract

The excess of nonequilibrium charge carriers due to heating by strong electric fieldsinfluences the nonlinear current–voltage characteristics in semiconductors substantially. Itis shown that in general the electron gas heating results in a change of the carrierconcentration in the conduction band due to the dependence of the recombination rate onthe electron temperature. This nonequilibrium carrier density leads to an extra nonlinearitycoefficient in the current–voltage characteristic curve even when the electron mobility isindependent of the electron temperature. These latter contributions in the nonlinear theoryof hot electrons are exemplified by an attractive potential of the impurity potential insemiconductors.