Ambipolar/unipolar conversion in graphene transistors by surface doping

作者：Feng, Tingting; Xie, Dan^*; Zhao, Haiming; Li, Gang; Xu, Jianlong; Ren, Tianling; Zhu, Hongwei

来源：Applied Physics Letters, 2013, 103(19): 193502.

DOI：10.1063/1.4827879

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An ambipolar/unipolar conversion of conduction polarity in bottom-gate graphene field-effect transistor (FET) was realized by intended/unintended surface doping. Exposing the graphene FET in air made it fully p-type while covering graphene with Al nanofilm or poly(ethylene imine) (PEI) layer yielded a recovery of ambipolar conduction. The alteration of the conduction polarity in graphene FET was due to hole or electron-doping effect on graphene. Distinct changes in carrier mobility and current-voltage relationship were discussed between graphene with Al and PEI doping, and the dielectric screening by PEI was proposed as the possible mechanism.

• 出版日期2013-11-4
• 单位清华大学