The effect of scattering centers on resonant tunneling in double barrier heterostructures

Abstract

A theoretical analysis of the effect of scattering centers on tunneling current in amorphous (a-SiC:H/a-Si:H/a-SiC:H) double barrier heterostructures (DBH) is presented in terms of the transfer matrix and Airy function approaches. We consider one localized center in the well of the DBH and take into account the random distribution of its position by making configurational average. We use the δ-type function to describe the perturbation potential of the centers. In agreement with experimental observations, we find resonant peaks arising from quantized states in the well even in the case of the presence of scattering centers. The effect of scattering is to lower the transmission probability and to shift and broaden the peak of the resonant tunneling spectrum. For the I–V characteristics the effect of scattering is to shift the resonance shoulders.