Tunneling devices based on graphene/black phosphorus van der Waals heterostructures

Abstract

Vertically stacked devices of two-dimensional layered materials (2DLMs) based on van der Waals heterostructures (vdWHs) have recently attracted considerable attention due to their good properties. A tunneling structure is presented in this paper that, unlike other tunneling structures, has no specific insulating two-dimensional materials, such as boron nitride. The tunneling structure is comprised of graphene and black phosphorus. Black phosphorus is chemically active, and can be easily oxidized in the air to form an insulating layer. A tunneling device was produced based on this characteristic of black phosphorus. The insulation layer was an oxide layer formed by the oxidation of black phosphorus. The structure takes advantage of the easy oxidation ability of black phosphorus. The presence of a black phosphorus oxide layer was determined by XPS analysis. The tunneling characteristics of the overlay structure were determined by measuring the current-voltage (I _d -V) curve of the device. Simulation studies showed that the oxidation layer was responsible for the tunneling effect. Compared with other black phosphorus devices, the photoelectric properties of the proposed device were greatly improved.

Keywords

• tunneling devices
• graphene
• black phosphorus