Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States.
Nano Lett. 2011 Nov 9;11(11):4759-63. doi: 10.1021/nl2025739. Epub 2011 Oct 10.
The bilayer graphene has attracted considerable attention for potential applications in future electronics and optoelectronics because of the feasibility to tune its band gap with a vertical displacement field to break the inversion symmetry. Surface chemical doping in bilayer graphene can induce an additional offset voltage to fundamentally affect the vertical displacement field and the band gap opening in bilayer graphene. In this study, we investigate the effect of chemical molecular doping on band gap opening in bilayer graphene devices with single or dual gate modulation. Chemical doping with benzyl viologen molecules modulates the displacement field to allow the opening of a transport band gap and the increase of the on/off ratio in the bilayer graphene transistors. Additionally, Fermi energy level in the opened gap can be rationally controlled by the amount of molecular doping to obtain bilayer graphene transistors with tunable Dirac points, which can be readily configured into functional devices, such as complementary inverters.
双层石墨烯因其具有通过垂直位移场来调节带隙的可能性而引起了人们的极大关注，这种可能性可以打破反转对称性，从而有望应用于未来的电子学和光电子学中。在双层石墨烯中进行表面化学掺杂可以引入额外的偏移电压，从而从根本上影响双层石墨烯中的垂直位移场和带隙打开。在这项研究中，我们研究了化学分子掺杂对具有单栅或双栅调制的双层石墨烯器件中带隙打开的影响。用苄基紫精分子进行化学掺杂可以调节位移场，从而打开输运带隙，并提高双层石墨烯晶体管的导通/关断比。此外，通过分子掺杂的量可以合理地控制打开的带隙中的费米能级，从而获得具有可调狄拉克点的双层石墨烯晶体管，这些晶体管可以很容易地配置成功能器件，如互补反相器。
