Hot-carrier thermal breakdown and S-type current-voltage characteristics in perforated graphene structures

Abstract

We investigate the carrier transport characteristics of perforated graphene layer (PGL) composed of arrays of interdigital coplanar graphene microribbons (GMRs) connected by graphene nanoribbon (GNR) bridges. We analyze their operation at room-temperature. Under an applied bias voltage, two-dimensional electron and hole systems (2DES and 2DHS) form in adjacent GMRs. The terminal current in these PGL structures is primarily governed by thermionic transport across the GNR bridges. As electrons and holes traverse the GNRs, they induce heating in the 2DES and 2DHS, creating a positive feedback loop between carrier heating and thermionic emission. This phenomenon, characterized as hot-carrier thermal breakdown, can give rise to S-shaped inter-GMR current-voltage characteristics. These unique transport properties make PGLs promising candidates for fast, voltage-controlled room-temperature switches and electromagnetic radiation detectors.