Bipolar electronic charge transport model under trap density Gaussian spatial distribution: application to dielectric polymer interfaces

Abstract

Our new approach consists of applying the Gaussian spatial distribution function to study the trapping process bipolar electronic charge transport at dielectric–dielectric as well as dielectric-electrode interfaces. Indeed, the application of the Gaussian spatial distribution function, to the traps spatial density distribution as well as to the corresponding trapping coefficients, has not been investigated so far for bipolar transport modeling in insulating and dielectric materials. In fact, this approach takes into account the non-uniformity of the trap density spatial distribution, which constitutes the main contribution that presents a more realistic aspect taking into account the existence of the inhomogeneities in the dielectric materials. Several numerical resolution techniques have been applied to the theoretical equations formulated with associated assumptions and physical conditions. The obtained results show several physical phenomena, such as charge accumulation and Maxwell–Wagner behavior. In this paper, to validate our approach, we have focused our investigations on the accumulation phenomenon of trapped charges. Our results are in good agreement with those obtained by the pulsed electro-acoustic experimental technique, for the example, epoxy–polyethylene interfaces.