Abstract

Although graphene has been studied as wonder materials for electronics due to its outstanding charge transport properties. its lack of an electronic bandgap has hindered its application to large-scale field-effect transistor (FET) circuits, thereby making bandgap opening a key priority. Further, the fabrication of graphene devices to date conventionally requires the transfer of graphene from its growth substrate to a target substrate, which introduces defects and negatively impacts the device performance. Overcoming these challenges, we demonstrate a transfer-free approach for the low-temperature growth (~100 °C) and in-situ doping of monolayer graphene, which enables FETs with cutting-edge performance and stability. With a focus on nitrogen-doped graphene, we realize n-type graphene FETs with an on-off ratio of ~2´108, a mobility of ~1,500 cm2V-1s-1, and a subthreshold swing of ~ 90 mVdec-1. Such devices are highly reproducible and exhibit high wafer-scale uniformity and thermal and bias-stress stability. Further, our approach is highly versatile, for instance also allowing the fabrication of p-type graphene FETs with a mobility of ~290 cm2V-1s-1 and an on-off ratio of 2´105.