Structural investigation of nanocrystalline graphene grown on (6√3 x 6√3)R30°-reconstructed SiC surfaces by molecular beam epitaxy

被引：14

作者：

Schumann, T. ^{[1
]}

Dubslaff, M. ^{[1
]}

Oliveira, M. H., Jr. ^{[1
]}

Hanke, M. ^{[1
]}

Fromm, F. ^{[2
]}

Seyller, T. ^{[2
]}

Nemec, L. ^{[3
]}

Blum, V. ^{[3
]}

Scheffler, M. ^{[3
]}

Lopes, J. M. J. ^{[1
]}

Riechert, H. ^{[1
]}

机构：

[1] Paul Drude Inst Festkorperelekt, D-10117 Berlin, Germany

[2] Tech Univ Chemnitz, Inst Phys, D-09126 Chemnitz, Germany

[3] Max Planck Gesell, Fritz Haber Inst, Theory Dept, D-14195 Berlin, Germany

来源：

NEW JOURNAL OF PHYSICS | 2013年 / 15卷

关键词：

FEW-LAYER GRAPHENE; SIZE GRAPHENE; LARGE-AREA; DEFECTS; SIC(0001); GRAPHITE;

D O I：

10.1088/1367-2630/15/12/123034

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Growth of nanocrystalline graphene films on (6 root 3 x 6 root 3)R30 degrees-reconstructed SiC surfaces was achieved by molecular beam epitaxy, enabling the investigation of quasi-homoepitaxial growth. The structural quality of the graphene films, which is investigated by Raman spectroscopy, increases with growth time. X-ray photoelectron spectroscopy proves that the SiC surface reconstruction persists throughout the growth process and that the synthesized films consist of sp(2)-bonded carbon. Interestingly, grazing incidence x-ray diffraction measurements show that the graphene domains possess one single in-plane orientation, are aligned to the substrate, and offer a noticeably contracted lattice parameter of 2.450 angstrom. We correlate this contraction with theoretically calculated reference values (all-electron density functional calculations based on the van der Waals corrected Perdew-Burke-Ernzerhof functional) for the lattice parameter contraction induced in ideal, free-standing graphene sheets by: substrate-induced buckling, the edges of limited-size flakes and typical point defects (monovacancies, divacancies, Stone-Wales defects).

引用

页数：16