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Coincident-site lattice matching during van der Waals epitaxy.

ABSTRACT: Van der Waals (vdW) epitaxy is an attractive method for the fabrication of vdW heterostructures. Here Sb2Te3 films grown on three different kind of graphene substrates (monolayer epitaxial graphene, quasi freestanding bilayer graphene and the SiC (6?3?×?6?3)R30° buffer layer) are used to study the vdW epitaxy between two 2-dimensionally (2D) bonded materials. It is shown that the Sb2Te3 /graphene interface is stable and that coincidence lattices are formed between the epilayers and substrate that depend on the size of the surface unit cell. This demonstrates that there is a significant, although relatively weak, interfacial interaction between the two materials. Lattice matching is thus relevant for vdW epitaxy with two 2D bonded materials and a fundamental design parameter for vdW heterostructures.

SUBMITTER: Boschker JE

PROVIDER: S-EPMC4677287 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Coincident-site lattice matching during van der Waals epitaxy.

Boschker Jos E JE Galves Lauren A LA Flissikowski Timur T Lopes Joao Marcelo J JM Riechert Henning H Calarco Raffaella R

Scientific reports 20151214

Van der Waals (vdW) epitaxy is an attractive method for the fabrication of vdW heterostructures. Here Sb2Te3 films grown on three different kind of graphene substrates (monolayer epitaxial graphene, quasi freestanding bilayer graphene and the SiC (6√3 × 6√3)R30° buffer layer) are used to study the vdW epitaxy between two 2-dimensionally (2D) bonded materials. It is shown that the Sb2Te3 /graphene interface is stable and that coincidence lattices are formed between the epilayers and substrate tha ...[more]

PMID: 26658715

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