All-Two-Dimensional-Material Hot Electron Transistor

In this letter, we report the first experimental realization of purely two-dimensional-material-based hot electron transistor (2D-HET) by the van der Waals stacking. We used ultra-thin graphene as the base, and WSe
₂
or
${h}$
-BN as the emitter-base or base-collector barriers. We quantitatively determined that the transport mechanism through the 2D barrier changes from the Fowler–Nordheim tunneling to the thermionic emission with the increase of temperature. In our 2D-HET, the dangling-bond-free 2D materials provide atomically sharp interfaces to suppress the hot electron scattering, which along with the optimization of the barriers, gives a relatively large collection efficiency of 99.95% and a relatively high current density of 233 A/cm
₂
in the family of graphene-base HETs.