▎ 摘　　要

NOVELTY - The graphene heterostructure has a first graphene layer, a second graphene layer, and a spacer layer positioned between the first and second graphene layers. Preferably, the spacer layer is made of hexagonal boron-nitride. Preferably, the spacer layer lies directly next to the first graphene layer, and the second graphene layer lies directly next to the spacer layer. USE - Graphene heterostructure used in fabrication of transistor (claimed) e.g. bipolar tunneling FET. ADVANTAGE - Enables fabrication of a transistor with high conductivity, one-atomic-layer thickness of graphene, and low density of states associated with its Dirac-like spectrum. Allows the transistor to achieve the potential for high frequency operation and large scale integration. Enables designing a transistor with a desired switching ratio by the appropriate choice of material to be used in conjunction with graphene. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method of making a graphene heterostructure; and (2) a transistor. DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of a multilayer sample, an optical image of the multilayer sample, and experimental results on quantum capacitance and simulations for different spacer thicknesses.