Probing the uniformity of hydrogen intercalation in quasi-free-standing epitaxial graphene on SiC by micro-Raman mapping and conductive atomic force microscopyShow others and affiliations
2019 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 30, no 28, article id 284003Article in journal (Refereed) Published
Abstract [en]
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.
Place, publisher, year, edition, pages
IOP PUBLISHING LTD , 2019. Vol. 30, no 28, article id 284003
Keywords [en]
epitaxial graphene; silicon carbide; hydrogen intercalation; Raman spectroscopy; conductive atomic force microscopy; Schottky barrier
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:liu:diva-156887DOI: 10.1088/1361-6528/ab134eISI: 000465981800003PubMedID: 30913546OAI: oai:DiVA.org:liu-156887DiVA, id: diva2:1318843
Note
Funding Agencies|Flag-ERA project GraNitE (MIUR) [0001411]; VR [2016-05362, 621-2014-5805, 2018-04962, 2017-04071]; SSF [SSF GMT14-0077, SSF RMA15-0024]; Angpanneforeningens Forskningsstiftelse [16-541]; GRIFONE (VR) [2015-06816]
2019-05-282019-05-282024-03-01