Graphene barristor, a triode device with a gate-controlled Schottky barrier

Updating the Triode with Graphene In early electronics, the triode—a vacuum device that combined a diode and an electrical grid—was used to control and amplify signals, but was replaced in most applications by solid-state silicon electronics. One characteristic of silicon-metal interfaces is that the Schottky barrier created—which acts as a diode—does not change with the work function of the metal—the Fermi level is pinned by the presence of surface states. Yang et al. (p. 1140 , published online 17 May) now show that for a graphene-silicon interface, Fermi-level pinning can be overcome and a triode-type device with a variable barrier, a “barristor,” can be made and used to create devices such as inverters.