▎ 摘　　要

A subthreshold slope model for the graphene vertical interlayer tunnel transistor is proposed analytically and results are compared and validated from numerical computations. It has been found that irrespective of the energy dependence in computation method, the subthreshold slope of an interlayer tunnel transistor cannot go below the thermionic limit of 60 mV/decade compared to that of a MOSFET. While thickness of the tunneling barrier, carrier effective mass inside the tunneling barrier, energy band gap between the barrier material and adjacent conductive sandwich layers and the tunneling bias determine the ultimate steepness of the subthreshold slope of such tunnel transistors, a realistic operation of interlayer tunnel transistor at a thin tunnel barrier will always result in a subthreshold slope far greater than the thermionic limit of 60 mV/decade.