Toward Ferroelectric Control of Monolayer MoS2

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Molybdenum disulfide (MoS2) is a key 2D material with promising electronic properties.
• Lithium niobate (LiNbO3) is a ferroelectric material with a tunable polarization pattern.
• Integrating 2D materials with ferroelectrics is challenging but offers novel device functionalities.

Purpose of the Study:

• To investigate the growth of single-layer MoS2 on periodically poled lithium niobate (PPLN).
• To determine if MoS2 growth can be templated by the ferroelectric polarization of the LiNbO3 substrate.
• To explore the electrical properties of MoS2 grown on differently polarized ferroelectric domains.

Main Methods:

• Chemical Vapor Deposition (CVD) for MoS2 film growth.
• Piezoresponse Force Microscopy (PFM) to probe surface polarization.
• Electrical transport measurements to analyze carrier behavior.

Main Results:

• Successful CVD growth of single-layer MoS2 on PPLN, maintaining substrate polarization.
• MoS2 growth preferentially occurs on ferroelectric domains polarized 'up'.
• MoS2 monolayers modulate the surface polarization of LiNbO3 domains.
• Electrical transport in MoS2 is sensitive to the underlying ferroelectric domain orientation.

Conclusions:

• Ferroelectric polarization of LiNbO3 can template MoS2 growth without lithography.
• MoS2 films exhibit distinct electrical properties based on substrate domain orientation.
• This approach enables nonvolatile ferroelectric gating for scalable MoS2-based devices.