• 文献标题:   Tunable Graphene Electronics with Local Ultrahigh Pressure
  • 文献类型:   Article
  • 作  者:   ARES P, PISARRA M, SEGOVIA P, DIAZ C, MARTIN F, MICHEL EG, ZAMORA F, GOMEZNAVARRO C, GOMEZHERRERO J
  • 作者关键词:   atomic force microscopy, chemical bonding, doping, graphene, ultrahigh pressure
  • 出版物名称:   ADVANCED FUNCTIONAL MATERIALS
  • ISSN:   1616-301X EI 1616-3028
  • 通讯作者地址:   Univ Autonoma Madrid
  • 被引频次:   6
  • DOI:   10.1002/adfm.201806715
  • 出版年:   2019

▎ 摘  要

Fine-tuning of graphene effective doping is achieved by applying ultrahigh pressures (>10 GPa) using atomic force microscopy (AFM) diamond tips. Specific areas in graphene flakes are irreversibly flattened against a SiO2 substrate. This work represents the first demonstration of local creation of very stable effective p-doped graphene regions with nanometer precision, as unambiguously verified by a battery of techniques. Importantly, the doping strength depends monotonically on the applied pressure, allowing a controlled tuning of graphene electronics. Through this doping effect, ultrahigh pressure modifications include the possibility of selectively modifying graphene areas to improve their electrical contact with metal electrodes, as shown by conductive AFM. Density functional theory calculations and experimental data suggest that this pressure level induces the onset of covalent bonding between graphene and the underlying SiO2 substrate. This work opens a convenient avenue to tuning the electronics of 2D materials and van der Waals heterostructures through pressure with nanometer resolution.