▎ 摘　　要

Graphene is considered a promising transistor component for future integrated circuits. Due to high operating speed and low power consumption, high on/off ratio and low off state current are ideal transistors. However, due to the inherent ambipolarity of graphene, a significant ambipolarity behavior with a fairly high off state current is usually observed in graphene transistors. In this work, an asymmetric gate design combined with a chemically doped method to suppress the ambipolarity of graphene transistors was reported. Thus, the off-state current is effectively reduced and the on-state current is increased. The on/off ratio is increased by nearly two orders of magnitude. Compare to the normal gate structure device, better threshold swing and smaller threshold voltage are obtained.