Ledge-directed epitaxy of continuously self-aligned single-crystalline nanoribbons of transition metal dichalcogenides

Abstract

Two-dimensional transition metal dichalcogenide nanoribbons are touted as the future extreme device downscaling for advanced logic and memory devices but remain a formidable synthetic challenge. Here, we demonstrate a ledge-directed epitaxy (LDE) of dense arrays of continuous, self-aligned, monolayer and single-crystalline MoS(2)nanoribbons on beta-gallium (iii) oxide (beta-Ga2O3) (100) substrates. LDE MoS(2)nanoribbons have spatial uniformity over a long range and transport characteristics on par with those seen in exfoliated benchmarks. Prototype MoS2-nanoribbon-based field-effect transistors exhibit high on/off ratios of 10(8)and an averaged room temperature electron mobility of 65 cm(2) V-1 s(-1). The MoS(2)nanoribbons can be readily transferred to arbitrary substrates while the underlying beta-Ga(2)O(3)can be reused after mechanical exfoliation. We further demonstrate LDE as a versatile epitaxy platform for the growth of p-type WSe(2)nanoribbons and lateral heterostructures made of p-WSe(2)and n-MoS(2)nanoribbons for futuristic electronics applications. Aligned arrays of single-crystalline monolayer TMD nanoribbons with high aspect ratios, as well as their lateral heterostructures, are realized, with the growth directed by the ledges on the beta-Ga(2)O(3)substrate. This approach provides an epitaxy platform for advanced electronics applications of TMD nanoribbons.