• 文献标题:   Routes to rupture and folding of graphene on rough 6H-SiC(0001) and their identification
  • 文献类型:   Article
  • 作  者:   TEMMEN M, OCHEDOWSKI O, BUSSMANN BK, SCHLEBERGER M, REICHLING M, BOLLMANN TRJ
  • 作者关键词:   graphene, kelvin probe force microscopy kpfm, local contact potential difference lcpd, noncontact atomic force microscopy ncafm, sic
  • 出版物名称:   BEILSTEIN JOURNAL OF NANOTECHNOLOGY
  • ISSN:   2190-4286
  • 通讯作者地址:   Univ Osnabruck
  • 被引频次:   4
  • DOI:   10.3762/bjnano.4.69
  • 出版年:   2013

▎ 摘  要

Twisted few layer graphene (FLG) is highly attractive from an application point of view, due to its extraordinary electronic properties. In order to study its properties, we demonstrate and discuss three different routes to in situ create and identify (twisted) FLG. Single layer graphene (SLG) sheets mechanically exfoliated under ambient conditions on 6H-SiC(0001) are modified by (i) swift heavy ion (SHI) irradiation, (ii) by a force microscope tip and (iii) by severe heating. The resulting surface topography and the surface potential are investigated with non-contact atomic force microscopy (NC-AFM) and Kelvin probe force microscopy (KPFM). SHI irradiation results in rupture of the SLG sheets, thereby creating foldings and bilayer graphene (BLG). Applying the other modification methods creates enlarged (twisted) graphene foldings that show rupture along preferential edges of zigzag and armchair type. Peeling at a folding over an edge different from a low index crystallographic direction can result in twisted BLG, showing a similar height as Bernal (or AA-stacked) BLG in NC-AFM images. The rotational stacking can be identified by a significant contrast in the local contact potential difference (LCPD) measured by KPFM.