Methods for the provision of metal contacts on a two-dimensional material layer structure

Abstract

This document provides a method for providing metal contacts on a two-dimensional material layer structure such as graphene. One such method includes: (i) providing a layer structure comprising a substrate (900) having a two-dimensional material layer structure (910) thereon, and an inorganic dielectric layer (920) on and across the two-dimensional material layer structure (910), wherein the dielectric layer (920) has a thickness of less than 80 nm; (ii) wet etching a set of portions of the dielectric layer (920) within each of a plurality of regions of the layer structure to expose a corresponding set of surface portions of the two-dimensional material layer structure (910) and forming a corresponding set of wells (915) in the dielectric layer (920), wherein each well has a cross-sectional area coplanar with the substrate of less than 900 µm² and a thickness of less than 30 nm. (iii) A maximum width of µm; and (iv) one or more metallization steps are performed by depositing one or more metals (925') and forming a plurality of contact pads (925), wherein each contact pad (925) is electrically connected to the two-dimensional material layer structure (910) through a set of metal vias (925a, Figure 10) filling one of the wells (915) of the corresponding set. Electronic devices that can be obtained by such methods are provided herein. Methods for the provision of metal contacts on a two-dimensional material layer structure such as graphene, one such method comprising: (i) providing a laminate structure comprising a substrate (900) having a two-dimensional material layer structure (910) thereon, and an inorganic dielectric layer (920) on and across the two-dimensional material layer structure (910), wherein the dielectric layer (920) has a thickness of less than 80 nm; (ii) wet-etching, within each of a plurality of regions of the laminate structure, a group of portions of the dielectric layer (920) to expose a corresponding group of surface portions of the two-dimensional material layer structure (910) and form a corresponding group of wells (915) in the dielectric layer (920), wherein each well has a cross-sectional area co-planar with the substrate of less than 900 µm2 and has a maximum width of less than 30 µm;(iii) performing one or more metallisation steps by depositing one or more metals (925’) and forming a plurality of contact pads (925), wherein each contact pad (925) is in electrical communication with the two-dimensional material layer structure (910) through a group of metal vias (925a, Fig 10) filling one of the corresponding group of wells (915). Electronic devices which may be obtained by such methods.;

Images