• 文献标题:   Probing the uniformity of hydrogen intercalation in quasi-free-standing epitaxial graphene on SiC by micro-Raman mapping and conductive atomic force microscopy
  • 文献类型:   Article
  • 作  者:   GIANNAZZO F, SHTEPLIUK I, IVANOV G, IAKIMOV T, KAKANAKOVAGEORGIEVA A, SCHILIRO E, FIORENZA P, YAKIMOVA R
  • 作者关键词:   epitaxial graphene, silicon carbide, hydrogen intercalation, raman spectroscopy, conductive atomic force microscopy, schottky barrier
  • 出版物名称:   NANOTECHNOLOGY
  • ISSN:   0957-4484 EI 1361-6528
  • 通讯作者地址:   CNR
  • 被引频次:   11
  • DOI:   10.1088/1361-6528/ab134e
  • 出版年:   2019

▎ 摘  要

In this paper, micro-Raman mapping and conductive atomic force microscopy (C-AFM) were jointly applied to investigate the structural and electrical homogeneity of quasi-free-standing monolayer graphene (QFMLG), obtained by high temperature decomposition of 4H-SiC(0001) followed by hydrogen intercalation at 900 degrees C. Strain and doping maps, obtained by Raman data, showed the presence of sub-micron patches with reduced hole density correlated to regions with higher compressive strain, probably associated with a locally reduced hydrogen intercalation. Nanoscale resolution electrical maps by C-AFM also revealed the presence of patches with enhanced current injection through the QFMLG/SiC interface, indicating a locally reduced Schottky barrier height (Phi(B)). The Phi(B) values evaluated from local I-V curves by the thermionic emission model were in good agreement with the values calculated for the QFMLG/SiC interface using the Schottky-Mott rule and the graphene holes density from Raman maps. The demonstrated approach revealed a useful and non-invasive method to probe the structural and electrical homogeneity of QFMLG for future nano-electronics applications.