▎ 摘　　要

The static and dynamic characteristics of top-gated graphene nanoribbon-based field-effect transistors were investigated. Multilayer graphene was synthesized by thermal decomposition of Si-face silicon carbide. The impact of the number of graphene layers on device performance was explored. It was found that, with the reduction of the layer number from ten to five, a significant improvement of direct-current characteristics and high-frequency performance can be observed. A high intrinsic current-gain cutoff frequency of 60 GHz and a maximum oscillation frequency of 28 GHz are reported.