石墨烯半浮栅场效应晶体管的制备与电学特性研究

Fabrication and electrical characteristics of graphene semi-floating gate field-effect transistors

基于石墨烯材料的半浮栅场效应晶体管因其非易失性的存储特性而被广泛研究。通过定点转移工艺制备了一种以少层石墨烯为沟道,六方氮化硼作为隧穿势垒层,石墨烯作为半浮栅电荷俘获层的石墨烯场效应晶体管。由于其独特的半浮栅结构,器件的转移特性曲线出现双狄拉克点。对器件转移特性曲线双狄拉克点现象进行了系统理论分析。另外,得到石墨烯浮栅器件的稳定保留特性,在200 s内,器件存储擦除电流差可以维持在20μA左右。所提出的研究有助于实现基于半浮栅结构的二维材料多功能光电子器件。

Semi-floating gate field-effect devices based on graphene have been extensively studied due to their nonvolatile memory characteristics.In this paper,a graphene field-effect device with few-layer graphene as the channel,hexagonal boron nitride as the tunnel barrier layer,and graphene as the charge trapping layer is fabricated.Because of its unique semi-floating gate structure,the transfer characteristic curve has double Dirac points,which are systematically studied.At the same time,we get the stable retention characteristics of the device.Within 200 s,the device program and erase current ratio can be maintained at about 20μA.Our research is helpful realizing two-dimensional optoelectronic devices based on the semi-floating structure.