Single-crystalline High-κ GdOCl dielectric for two-dimensional field-effect transistors

Area of Science:

• Materials Science
• Nanotechnology
• Solid-State Physics

Background:

• Two-dimensional (2D) dielectrics are crucial for overcoming scaling limits in miniaturized integrated circuits.
• Existing 2D dielectrics suffer from low crystallinity, reduced dielectric constants, and limited synthesis methods.
• High-mobility semiconductors require advanced dielectric materials for improved device performance.

Purpose of the Study:

• To develop a controllable synthesis method for ultra-thin 2D dielectrics with enhanced properties.
• To investigate the dielectric and electrical characteristics of novel gadolinium oxychloride (GdOCl) nanosheets.
• To evaluate the performance of GdOCl in field-effect transistors (FETs) and logic gates for nanoelectronic applications.

Main Methods:

• Controllable synthesis of ultra-thin gadolinium oxychloride (GdOCl) nanosheets.
• Chloride hydrate-assisted chemical vapor deposition (CVD) technique.
• Fabrication and characterization of top-gated GdOCl/MoS2 field-effect transistors (FETs).

Main Results:

• GdOCl nanosheets exhibit a high dielectric constant (κ) of 15.3 and high breakdown field strength (> 9.9 MV/cm).
• Minimal gate leakage currents (approx. 10^-6 A/cm^2) and excellent transistor performance with negligible hysteresis (~5 mV).
• Demonstrated functional logic gates using GdOCl/MoS2 FETs, indicating potential for complex circuits.

Conclusions:

• The chloride hydrate-assisted CVD method enables controllable synthesis of high-quality 2D GdOCl nanosheets.
• GdOCl demonstrates superior dielectric properties, making it a promising candidate for next-generation nanoelectronics.
• The developed 2D GdOCl dielectric is suitable for fabricating high-speed operated nanoelectronic devices and logic circuits.