具有石墨烯辅助导电层的碳纳米管射频场效应晶体管

Carbon Nanotube Radio Frequency Field Effect Transistor with Graphene Conductive Layer

采用纯度高于99%的半导体型单壁碳纳米管分散液制备碳纳米管无序网络作为射频场效应晶体管的有源沟道材料,使用单层石墨烯作为器件源漏的辅助接触电极,研制出T型栅结构的碳纳米管射频场效应晶体管。采用石墨烯加强晶体管器件的欧姆接触,降低器件的寄生电阻和寄生电容,提高器件的高频性能。实验制备的碳纳米管射频晶体管沟道长度为90nm左右,电流增益截止频率f_T达到13.5GHz,最大振荡频率f_(max)达到10.5GHz,体现了碳纳米管在射频器件应用领域的技术潜力。

FETs were designed and fabricated by using SWNT network as channel layer deposited from 99% high-purity semiconducting SWNT solution.Single-layer graphene was employed to improve the source and drain contacts of the FETs.The effective reduction of the parasitic resistance and capacitance due to the employment of extremely thin graphene facilitating the charge carrier transfer between the channel and the contacts improves the high-frequency performance of the device.The FET with a gate length of 90 nm showed a current-gain cutoff frequency（fT）of 13.1 GHz and a maximum oscillation frequency（fmax）of 10.5 GHz.Its high-frequency characteristics indicate carbon nanotubes′potential for RF applications.