Electrically-activated source extension graphene nanoribbon field effect transistor: Novel attributes and design considerations for suppressing short channel effects

Abstract

In this paper a double gate graphene nanoribbon field effect transistor with electrically-activated source extension is proposed. Source region of the proposed structure includes two sections, an electrically-activated extension and a doped section. The electrically extension, which is located between doped source section and gate region, is biased independent of the gate to form a virtual extension for source. The electrically-activated extension creates a step in potential profile which increases the horizontal distance between conduction and valance bands at channel to source junction. This step reduces the probability of band to band tunneling, lowers the leakage current and improves drain induced barrier lowering. The devices have been simulated based on self consistent solution of Poisson and Schrodinger equations within non-equilibrium Green’s function formalism. In addition, the effects of the edge and third nearest neighbor are included for more accurate outcomes. Simulations show that the proposed structure is a more reliable device because of its higher ON/Off current ratio, shorter delay time, and smaller power delay product beside lower subthreshold swing than conventional graphene nanoribbon field effect transistor.