Ionically Connected Floating Electrodes for Long-Distance (>1 mm) Coplanar-Gating Graphene Transistors

Area of Science:

• Materials Science
• Electrical Engineering
• Nanoscience

Background:

• Electric double-layer transistors (EDLTs) utilize ion migration in electrolytes for transistor operation.
• Unconventional EDLT configurations place the gate electrode coplanar with the device channel.
• The performance of coplanar-gated EDLTs is sensitive to electrolyte layer distance.

Purpose of the Study:

• To investigate the impact of electrolyte layer distance on coplanar-gated EDLT performance.
• To develop strategies for improving the dynamic characteristics of remote-gated EDLTs.
• To demonstrate an effective method for achieving long-range gating in EDLTs.

Main Methods:

• Fabrication of EDLTs with coplanar gate electrodes.
• Systematic variation of electrolyte layer thickness and distance.
• Implementation of multiple coplanar floating gates bridged by ionic dielectric layers.
• Characterization of transistor dynamic performance at varying gate-channel distances.

Main Results:

• Transistor performance degrades significantly with increasing gate-channel distance in conventional coplanar EDLTs.
• The proposed design with multiple segmented electrolyte layers and floating gates mitigates performance degradation.
• Effective operation of EDLTs was achieved with gate distances exceeding 1 mm using the novel configuration.

Conclusions:

• The distance between the gate and channel critically affects electric double-layer formation and EDLT performance.
• Multiple coplanar floating gates bridged by ionic dielectric layers offer a viable solution for long-range gating in EDLTs.
• This approach enables robust operation of unconventional EDLTs over extended distances, broadening their application potential.