Temperature dependence of injection-limited currents in dielectrics

It is noted that the temperature dependence of ILC (injection-limited current) is naturally described by thermally activated escape of the carriers from the Coulombic potential well. It is usually assumed and often observed that the activation energy of this process is a temperature-independent quantity. It is shown that the activation energy is, in general, a function of temperature; the shape of the function is determined by spatial distribution of the source current. The Arrhenius law appears as a consequence of expressing the weak gradient function characterizing the injecting contact by a δ function, which is physically unjustified and must be questioned