Full Control of Solid-State Electrolytes for Electrostatic Gating.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Ionic gating is crucial for field-effect transistors (FETs) but traditionally uses top electrolyte gates, limiting experiments and complicating fabrication.
• Existing solid-state electrolyte gates suffer from spurious phenomena, hindering transistor performance, control, and reproducibility.

Purpose of the Study:

• To explore Lithium-ion conducting glass-ceramics (LICGCs) as solid-state electrolytes for ionic gating.
• To identify and resolve the causes of spurious phenomena in solid-state ionic gating.
• To demonstrate high-performance transistors and novel applications enabled by LICGCs.

Main Methods:

• Investigated Lithium-ion conducting glass-ceramics (LICGCs) for ionic gating applications.
• Analyzed and identified the origins of spurious phenomena affecting transistor operation.
• Fabricated and characterized field-effect transistors (FETs) using LICGCs in a back-gate configuration.

Main Results:

• Successfully identified and mitigated processes causing spurious phenomena, enabling reproducible transistor operation.
• Demonstrated properly functioning transistors with high-density ambipolar operation and significant gate capacitance.
• Utilized ionic-gate spectroscopy on 2D transition-metal dichalcogenides to determine bandgaps and achieve electron densities >10^14 cm^-2.
• Achieved gate-induced superconductivity in MoS2 multilayers.
• Enabled surface-sensitive techniques and double ionic gating for independent control.

Conclusions:

• LICGCs offer a robust solution for solid-state ionic gating, overcoming limitations of previous methods.
• The back-gate configuration with LICGCs facilitates advanced characterization and novel device architectures.
• This work paves the way for new applications in electronic devices and fundamental condensed matter studies.