Inter-band tunneling mechanisms via dopant-induced energy states in low-dimensional si tunnel diodes

Abstract

Inter-band tunneling in Si is a key mechanism for Esaki diodes and tunnel FETs. In nanoscale devices, the dopant states under high built-in electric field may significantly affect inter-band tunneling transport. Here, we introduce firsttime observations from measurements of nanoscale Si tunnel diodes of two main effects: (i) splitting of dopant minibands in high electric field, similarly to the Wannier-Stark ladder; (ii) single-charge tunneling transport via donor-acceptor pairs aligned by the electric field. These phenomena produce distinguishable effects to enhance inter-band tunneling current.