Gate-Induced Metal–Insulator Transition in MoS₂ by Solid Superionic Conductor LaF ₃

Journal Article · Fri Mar 23 00:00:00 EDT 2018 · Nano Letters

DOI: https://doi.org/10.1021/acs.nanolett.7b05377 · OSTI ID:1438821

Wu, Chun-Lan  ^[1]; Yuan, Hongtao ^[2]; Li, Yanbin  ^[1]; Gong, Yongji ^[3]; Hwang, Harold Y. ^[4]; Cui, Yi  ^[5]

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1. Stanford Univ., CA (United States). Dept. of Material Science and Engineering
2. Stanford Univ., CA (United States). Dept. of Material Science and Engineering; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Nanjing Univ. (China). National Lab. of Solid-State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures
3. Stanford Univ., CA (United States). Dept. of Material Science and Engineering; Beihang Univ., Beijing (China). School of Material Science and Engineering
4. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States). Dept. of Applied Physics
5. Stanford Univ., CA (United States). Dept. of Material Science and Engineering; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)

Electric-double-layer (EDL) gating with liquid electrolyte has been a powerful tool widely used to explore emerging interfacial electronic phenomena. Due to the large EDL capacitance, a high carrier density up to 10¹⁴ cm^–2 can be induced, directly leading to the realization of field-induced insulator to metal (or superconductor) transition. However, the liquid nature of the electrolyte has created technical issues including possible side electrochemical reactions or intercalation, and the potential for huge strain at the interface during cooling. In addition, the liquid coverage of active devices also makes many surface characterizations and in situ measurements challenging. Here, we demonstrate an all solid-state EDL device based on a solid superionic conductor LaF₃, which can be used as both a substrate and a fluorine ionic gate dielectric to achieve a wide tunability of carrier density without the issues of strain or electrochemical reactions and can expose the active device surface for external access. Based on LaF₃ EDL transistors (EDLTs), we observe the metal–insulator transition in MoS₂. Interestingly, the well-defined crystal lattice provides a more uniform potential distribution in the substrate, resulting in less interface electron scattering and therefore a higher mobility in MoS₂ transistors. Finally, this result shows the powerful gating capability of LaF₃ solid electrolyte for new possibilities of novel interfacial electronic phenomena.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1438821
• Journal Information: Nano Letters, Journal Name: Nano Letters Journal Issue: 4 Vol. 18; ISSN 1530-6984
• Publisher: American Chemical SocietyCopyright Statement
• Country of Publication: United States
• Language: English