ReportNANOMATERIALS

Robust epitaxial growth of two-dimensional heterostructures, multiheterostructures, and superlattices

+ See all authors and affiliations

Science  03 Aug 2017:
eaan6814
DOI: 10.1126/science.aan6814

You are currently viewing the abstract.

View Full Text

Abstract

We report a general synthetic strategy for highly robust growth of diverse heterostructures, multiheterostructures, and superlattices from two-dimensional (2D) atomic crystals. A reverse flow during the temperature swing stage in sequential vapor deposition growth process allowed us to cool the existing 2D crystals to prevent undesired thermal degradation and uncontrolled homogeneous nucleation, thus enabling highly robust block-by-block epitaxial growth. Raman and photoluminescence mapping studies showed that a wide range of 2D heterostructures (such as WS2-WSe2 and WS2-MoSe2), multiheterostructures (such as WS2-WSe2-MoS2 and WS2-MoSe2-WSe2), and superlattices (such as WS2-WSe2-WS2-WSe2-WS2) were readily prepared with precisely controlled spatial-modulation. Transmission electron microscope studies show clear chemical modulation with atomically sharp interfaces. Electrical transport studies of WSe2-WS2 lateral junctions show well-defined diode characteristics with a rectification ratio up to 105.

View Full Text