Determination of the Spacing Between Hydrogen-Intercalated Quasi-Free-Standing Monolayer Graphene and 6H-SiC(0001) Using Total-Reflection High-Energy Positron Diffraction

Abstract

We have investigated the structure of hydrogen-intercalated quasi-free-standing monolayer graphene (QFMLG) grown on 6H-SiC(0001) by employing total-reflection high-energy positron diffraction (TRHEPD). At least nine diffraction spots of the zeroth order Laue zone were resolved along <11-20> and three along <1-100>, which are assigned to graphene, SiC and higher order spots from multiple diffraction on both lattices. We further performed rocking curve analysis based on the full dynamical diffraction theory to precisely determine the spacing between QFMLG and the SiC substrate. Our study yields a spacing of d = 4.18(6)Å that is in excellent agreement with the results from density-functional theory (DFT) calculations published previously.

References in corpus (6)

• The electronic properties of graphene
• Chiral tunneling and the Klein paradox in graphene
• Epitaxial graphene
• Positrons in Surface Physics
• Silicon carbide stacking-order-induced doping variation in epitaxial graphene
• Data-driven sensitivity analysis in a total-reflection high-energy positron diffraction (TRHEPD) experiment of the Si${}_4$O${}_5$N${}_3$ / 6H-SiC (0001)-($\sqrt{3}\times \sqrt{3}$) R30${}^{\circ }$