Dopant-assisted tunnel-current enhancement in two-dimensional Esaki diodes

We study ultrathin (2D) lateral Si Esaki tunneling diodes, and find that anomalous current peaks and humps are observed to be superimposed on the ordinary negative differential conductance (NDC). The remarkable enhancement of interband tunneling current is primarily ascribed to resonant tunneling via gap-states created by large potential fluctuation due to prominent inhomogeneity of dopant distribution (dopant-clusters) in the 2D depletion region.