Title: Selective Transfer of Rotationally Commensurate MoS₂ from an Epitaxially Grown van der Waals Heterostructure

Abstract

We report that large-scale synthesis of high-quality two-dimensional (2D) semiconductors is critical for their incorporation in emerging electronic and optoelectronic technologies. In particular, chemical vapor deposition (CVD) of transition-metal dichalcogenides (TMDs) via van der Waals epitaxy on epitaxial graphene (EG) leads to rotationally commensurate TMDs in contrast to randomly aligned TMDs grown on amorphous oxide substrates. However, the interlayer coupling between TMDs and EG hinders the investigation and utilization of the intrinsic electronic properties of the resulting TMDs, thus requiring their isolation from the EG growth substrate. To address this issue, we report here a technique for selectively transferring monolayer molybdenum disulfide (MoS₂) from CVD-grown MoS₂-EG van der Waals heterojunctions using copper (Cu) adhesion layers. The choice of Cu as the adhesion layer is motivated by density functional theory calculations that predict the preferential binding of monolayer MoS₂ to Cu in contrast to graphene. Atomic force microscopy and optical spectroscopy confirm the large-scale transfer of rotationally commensurate MoS₂ onto SiO₂/Si substrates without cracks, wrinkles, or residues. Furthermore, the transferred MoS₂ shows high performance in field-effect transistors with mobilities of up to 30 cm²/V s and on/off ratios of up to 10⁶ at room temperature. Lastly, this transfer technique can likelymore » be generalized to other TMDs and related 2D materials grown on EG, thus offering a broad range of benefits in nanoelectronic, optoelectronic, and photonic applications.« less

Authors:

Kang, Junmo ^[1]; Balla, Itamar  ^[1];

• Search DOE PAGES for author "Balla, Itamar"
• Search DOE PAGES for ORCID "0000-0002-9358-5743"

Liu, Xiaolong  ^[1];

• Search DOE PAGES for author "Liu, Xiaolong"
• Search DOE PAGES for ORCID "0000-0002-6186-5257"

Bergeron, Hadallia ^[1]; Kim, Soo ^[1]; Wolverton, Christopher  ^[1];

• Search DOE PAGES for author "Wolverton, Christopher"
• Search DOE PAGES for ORCID "0000-0003-2248-474X"

Hersam, Mark C.  ^[1]

• Search DOE PAGES for author "Hersam, Mark C."
• Search DOE PAGES for ORCID "0000-0003-4120-1426"

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+ Show Author Affiliations

1. Northwestern Univ., Evanston, IL (United States)

Publication Date:

Fri Nov 16 00:00:00 EST 2018

Research Org.:

Energy Frontier Research Centers (EFRC) (United States). Center for Light Energy Activated Redox Processes (LEAP); Northwestern Univ., Evanston, IL (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1566489

Grant/Contract Number:  

SC0001059

Resource Type:

Accepted Manuscript

Journal Name:

Chemistry of Materials

Additional Journal Information:

Journal Volume: 30; Journal Issue: 23; Journal ID: ISSN 0897-4756

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; catalysis (homogeneous); catalysis (heterogeneous); solar (photovoltaic); solar (fuels); optics; phonons; photosynthesis (natural and artificial); bio-inspired; hydrogen and fuel cells; charge transport; magnetism and spin physics; materials and chemistry by design; mesostructured materials; synthesis (novel materials); synthesis (self-assembly); synthesis (scalable processing)