Controlled Synthesis of Topological Insulator Nanoplate Arrays on Mica

Abstract

The orientation- and position-controlled synthesis of single-crystal topological insulator (Bi(2)Se(3) and Bi(2)Te(3)) nanoplate arrays on mica substrates was achieved using van der Waals epitaxy. Individual ultrathin nanoplates with the lateral dimension up to ~0.1 mm or uniform thickness down to 1-2 nm were produced. Single-Dirac-cone surface states of nanoplate aggregates were confirmed by angle-resolved photoemission spectroscopy measurements. The large-grain-size, single-crystal nanoplate arrays grown on mica can act as facile platforms for a combination of spectroscopy and in situ transport measurements, which may open up new avenues for studying exotic physical phenomena, surface chemical reactions, and modification in topological insulators.

Architectured van der Waals epitaxy of ZnO nanostructures on hexagonal BN

“…It is also expected that the selective vdW epitaxy can be exploited for fabricating smooth ZnO thin film structures by combining two processes required to grow the film structures: (i) formation of high-density regular arrays of nuclei (or nanostructures) that are sufficiently close to coalesce to form films, and (ii) epitaxial lateral overgrowth on the siteselectively formed nanostructures. Notably, Liu and co-workers 44 reported that selected-area chemical surface modification inhibited growth, but only the intact substrate area contributed to the maskless site-selective vdW epitaxy of Bi 2 Se 3 , Bi 2 Te 3 and In 2 Se 3 45 nanoplates with the desired spatial arrangements.…”

Seeded growth of highly crystalline molybdenum disulphide monolayers at controlled locations

“…Control over the position of MoS 2 flakes on oxidized silicon has been reported through the use of stamping 18 and masking 19 techniques, but neither of these allowed for the creation of large (tens of micrometres) monolayer domains at predetermined locations with micrometre-scale resolution. Substrate patterning has been used to control nucleation and growth of crystalline flakes of two-dimensional topological insulator materials on mica 20 , but it remains unclear whether this approach can be generalized to MoS 2 on oxidized silicon. Seeding techniques that allow growth at defined locations are well established for graphene 21,22 , and equivalent approaches for MoS 2 synthesis are highly desirable.…”

Tuning the composition of ternary Bi2Se3xTe3(1-x) nanoplates and their Raman scattering investigations

“…For Van der Waals epitaxy, fluorophlogopite mica is an ideal substrate, which has a layered structure and no danging bonds on fresh surface. 16,17 Notably, the CVD growth of Bi 2 Se 3x Te 3(1-x) can be achieved on other plane substrates, such as graphite, glass, etc as well.…”