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 MoS2 nanoribbons on β-gallium (iii) oxide (β-Ga2O3) (100) substrates. LDE MoS2 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 108 and an averaged room temperature electron mobility of 65 cm2 V−1 s−1. The MoS2 nanoribbons can be readily transferred to arbitrary substrates while the underlying β-Ga2O3 can be reused after mechanical exfoliation. We further demonstrate LDE as a versatile epitaxy platform for the growth of p-type WSe2 nanoribbons and lateral heterostructures made of p-WSe2 and n-MoS2 nanoribbons for futuristic electronics applications.
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The data from this study are available from the corresponding authors on reasonable request.
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V.T. and J.-H.F. are indebted to the support from the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under award no. OSR-2018-CARF/CCF-3079. V.T. acknowledges support from the KAUST Catalysis Center (KCC) and physical science division. C.P.C., T.-A.C., M.-Y.L. and L.-J.L. thank the Taiwan Semiconductor Manufacturing Company (TSMC). W.-H.C. acknowledges support from the Ministry of Science and Technology of Taiwan (MOST-108-2119-M-009-011-MY3, MOST-107-2112-M-009-024-MY3) and from the CEFMS of National Chiao Tung University supported by the Ministry of Education of Taiwan. V.T. and A.A. thank C.-H. Lien and L. Cavallo for their support; H.-L. Tang; M.-H. Chiu; and C.-C. Tseng for assistance with device architecture and CVD.
The authors declare no competing interests.
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Aljarb, A., Fu, J., Hsu, C. et al. Ledge-directed epitaxy of continuously self-aligned single-crystalline nanoribbons of transition metal dichalcogenides. Nat. Mater. (2020). https://doi.org/10.1038/s41563-020-0795-4