▎ 摘　　要

In this paper we investigate the upper limit performance of bilayer graphene (BLG) and graphene nanoribbon (GNR) field effect transistors (FETs) based on a first principles approach We have found that GNR FETs with ribbon widths of about 3-4 nm exhibit better device performance than n channel Si metal-oxide-semiconductor FETs and InP high electron mobility transistors (HEMTs) Although a BLG FET shows an inferior performance potential to GNR FETs with a similar band gap it is comparable to InP HEMTs The present simulation study indicates that both GNR and BLG are expected to be a post Si channel material for high speed digital switches in logic circuits (C) 2010 The Japan Society of Applied Physics