Short-Channel Double-Gate FETs with Atomically Precise Graphene Nanoribbons

Abstract

High performance graphene nanoribbon (GNR) transistors require seamless integration of GNRs with high-k dielectrics, which remains unexplored. This work evaluates performance of bottom-up synthesized 9-atom armchair GNRs (9-AGNRs) in short channel back-gate (BG) and double-gate (DG) FETs. Top-gate (TG) dielectric bilayers consisting of 1-1.25 nm Al2O3 and 2.5 nm HfO2 are deposited on 9-AGNRFETs with a 5.5 nm HfO2 BG dielectric. Devices exhibit excellent ION/IOFF up to 105 and ION up to 60 µA/µm (2.4 µA per GNR). DG enables improved subthreshold swing (SS) and low hysteresis owing to its superior electrostatic control. We also identify and quantify through numerical simulations the improvements in materials and process that would enable GNRs with performance close to outstanding theoretically predicted metrics.