• 文献标题:   Electronic properties of epitaxial graphene residing on SiC facets probed by conductive atomic force microscopy
  • 文献类型:   Article
  • 作  者:   GIANNAZZO F, DERETZIS I, NICOTRA G, FISICHELLA G, SPINELLA C, ROCCAFORTE F, LA MAGNA A
  • 作者关键词:   graphene, sic, electronic transport, conductive atomic force microscopy
  • 出版物名称:   APPLIED SURFACE SCIENCE
  • ISSN:   0169-4332 EI 1873-5584
  • 通讯作者地址:   CNR IMM
  • 被引频次:   7
  • DOI:   10.1016/j.apsusc.2013.10.041
  • 出版年:   2014

▎ 摘  要

In this paper, the electronic transport in few layer graphene epitaxially grown on the Si face of 8 degrees off-axis 4H-SiC has been investigated using conductive atomic force microscopy (CAFM). The comparison between the two dimensional morphology and current maps in epitaxial graphene (EG) residing over the stepped SiC surface revealed a local resistance increase of EG over the (11 - 2n) facets with respect to the(0001) basal plane. This is consistent with a significant reduction of the carrier concentration, possibly approaching to the neutrality, in EG residing on facets with respect to the high n-type doping (similar to 10(13) cm(-2)) commonly found in EG on the basal plane. The observed difference can be ascribed to a different interfacestructure between EG and SiC on the two faces. The results of these nanoscale measurements allow us to explain the typically observed macroscopic anisotropy in EG conductivity with respect to the substrate steps orientation. (C) 2013 Elsevier B. V. All rights reserved.