Protecting the properties of monolayer MoS2 on silicon based substrates with an atomically thin buffer

Man, Michael K. L.; Deckoff-Jones, Skylar; Winchester, Andrew; Shi, Guangsha; Gupta, Gautam; Mohite, Aditya D.; Kar, Swastik; Kioupakis, Emmanouil; Talapatra, Saikat; Dani, Keshav M.

doi:10.1038/srep20890

Title: Protecting the properties of monolayer MoS₂ on silicon based substrates with an atomically thin buffer

Journal Article · Fri Feb 12 00:00:00 EST 2016 · Scientific Reports

DOI:https://doi.org/10.1038/srep20890· OSTI ID:1259305

Man, Michael K. L. ^[1]; Deckoff-Jones, Skylar ^[1]; Winchester, Andrew ^[1]; Shi, Guangsha ^[2]; Gupta, Gautam ^[3]; Mohite, Aditya D. ^[3]; Kar, Swastik ^[4]; Kioupakis, Emmanouil ^[2]; Talapatra, Saikat ^[5]; Dani, Keshav M. ^[1]

Okinawa Institute of Science and Technology Graduate Univ., Okinawa (Japan)
Univ. of Michigan, Ann Arbor, MI (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Northeastern Univ., Boston, MA (United States)
Okinawa Institute of Science and Technology Graduate Univ., Okinawa (Japan); Southern Illinois Univ., Carbondale, IL (United States)

Semiconducting 2D materials, like transition metal dichalcogenides (TMDs), have gained much attention for their potential in opto-electronic devices, valleytronic schemes, and semi-conducting to metallic phase engineering. However, like graphene and other atomically thin materials, they lose key properties when placed on a substrate like silicon, including quenching of photoluminescence, distorted crystalline structure, and rough surface morphology. The ability to protect these properties of monolayer TMDs, such as molybdenum disulfide (MoS₂), on standard Si-based substrates, will enable their use in opto-electronic devices and scientific investigations. Here we show that an atomically thin buffer layer of hexagonal-boron nitride (hBN) protects the range of key opto-electronic, structural, and morphological properties of monolayer MoS₂ on Si-based substrates. The hBN buffer restores sharp diffraction patterns, improves monolayer flatness by nearly two-orders of magnitude, and causes over an order of magnitude enhancement in photoluminescence, compared to bare Si and SiO₂ substrates. Lastly, our demonstration provides a way of integrating MoS₂ and other 2D monolayers onto standard Si-substrates, thus furthering their technological applications and scientific investigations.

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Research Organization:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Organization:: USDOE Office of Science (SC)

Grant/Contract Number:: AC02-05CH11231; DMR-1254314; W911NF-11-1-0362

OSTI ID:: 1259305

Journal Information:: Scientific Reports, Vol. 6; ISSN 2045-2322

Publisher:: Nature Publishing GroupCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 52 works

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Title: Protecting the properties of monolayer MoS2 on silicon based substrates with an atomically thin buffer

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Title: Protecting the properties of monolayer MoS₂ on silicon based substrates with an atomically thin buffer