A Graphene Base Transistor for Potential Terahertz Application

Graphene base transistors have been proposed for THz applications, however, the so far employed tunnel emitter makes this goal challenging because that an emitter potential barrier as low as 0.4 eV is needed which is difficult to achieve. Here, we demonstrate a silicon-graphene-germanium graphene base transistor which employs a Schottky emitter. The Schottky emitter junction shows both a largest on-current and a smallest capacitance leading to about 1000 times improvement of the alpha cut-off frequency of the transistor compared with the ones with tunnel emitters. A THz application for the proposed transistor is expected by further engineering, and direction of future development is discussed.