†SKKU Advanced Institute of Nanotechnology (SAINT), ‡Department of Physics, and §School of Chemical Engineering, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
ACS Nano. 2015 Apr 28;9(4):4354-61. doi: 10.1021/acsnano.5b01791. Epub 2015 Apr 1.
A customized graphene doping method was developed involving stamping using a chemically functionalized rubber lens as a novel design strategy for fabricating advanced two-dimensional (2D) materials-based electronic devices. Our stamping strategy enables deterministic control over the doping level and the spatial pattern of the doping on graphene. The dopants introduced onto graphene were locally and continuously controlled by directly stamping dopants using a chemically functionalized hemispherical rubber lens onto the graphene. The rubber lens was functionalized using two different dopants: poly(ethylene imine) to achieve n-type doping and bis(trifluoromethanesulfonyl)amine to achieve p-type doping. The graphene doping was systematically controlled by varying both the contact area (between the rubber lens and the graphene) and the contact time. Graphene doping using a stamp with a chemically functionalized rubber lens was confirmed by both Raman spectroscopy and charge transport measurements. We theoretically modeled the conductance properties of the spatially doped graphene using the effective medium theory and found excellent agreement with the experimental results. Finally, complementary inverters were successfully demonstrated by connecting n-type and p-type graphene transistors fabricated using the stamping doping method. We believe that this versatile doping method for controlling charge transport in graphene will further promote graphene electronic device applications. The doping method introduced in this paper may also be applied to other emergent 2D materials to tightly modulate the electrical properties in advanced electronic devices.
开发了一种定制的石墨烯掺杂方法，涉及使用化学功能化橡胶透镜进行冲压，这是一种用于制造先进二维（2D）材料基电子器件的新颖设计策略。我们的冲压策略能够对石墨烯的掺杂水平和掺杂的空间图案进行确定性控制。通过使用化学功能化的半球形橡胶透镜直接将掺杂剂冲压到石墨烯上来实现对石墨烯上掺杂剂的局部和连续控制。使用两种不同的掺杂剂对橡胶透镜进行功能化：聚乙烯亚胺用于实现 n 型掺杂，双（三氟甲烷磺酰基）胺用于实现 p 型掺杂。通过改变橡胶透镜与石墨烯之间的接触面积（接触面积）和接触时间，系统地控制石墨烯的掺杂。通过 Raman 光谱和电荷输运测量证实了使用化学功能化橡胶透镜的压印石墨烯掺杂。我们使用有效介质理论对空间掺杂石墨烯的电导特性进行了理论建模，并与实验结果吻合得很好。最后，通过连接使用压印掺杂方法制造的 n 型和 p 型石墨烯晶体管，成功地演示了互补型逆变器。我们相信，这种用于控制石墨烯中电荷输运的多功能掺杂方法将进一步推动石墨烯电子器件的应用。本文介绍的掺杂方法也可应用于其他新兴的 2D 材料，以紧密调节先进电子设备中的电性能。
