A device comprising: at least one first layer, such as a graphene layer, at least one second layer of transition metal dichalcogenide, wherein the at least one first layer and the at least one second layer of transition metal dichalcogenide form at least one heterojunction. The first and second layers are laterally displaced but may overlap over a length of 0 nm to 500 nm. A low-resistance contact is formed. The device can be a transistor including a field effect transistor. The layers can be formed by chemical vapor deposition. The graphene can be heavily p-doped. Transistor performance data are described.