Wide Bandgap Lanthanide Oxybromides High-κ Dielectrics for High-Performance Two-Dimensional Electronics

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• High-κ single-crystal dielectrics are crucial for advanced 2D electronics.
• Schottky emission in conventional dielectrics causes high leakage current, limiting device performance.
• A wide bandgap is essential for effective dielectric materials in 2D devices.

Purpose of the Study:

• To explore 2D lanthanide oxybromides (LnOBr) as novel high-κ dielectrics.
• To investigate the bandgap, thickness tunability, and crystal quality of LnOBr materials.
• To evaluate the dielectric properties and device performance of LaOBr.

Main Methods:

• Synthesis of 2D LnOBr single crystals using chemical vapor deposition.
• Characterization of bandgap (>5.7 eV), dielectric constant (14.8), leakage current (<10⁻⁶ A cm⁻²), and breakdown field strength (14.2 MV cm⁻¹).
• Fabrication and testing of LaOBr top-gate MoS₂ transistors and integrated inverters.

Main Results:

• LnOBr materials exhibit wide bandgaps, tunable thickness, and high-quality single-crystal structures.
• 2D LaOBr demonstrated excellent insulating properties with a high dielectric constant and low leakage current.
• LaOBr-based MoS₂ transistors showed superior performance, including high on/off ratio (10⁷) and negligible hysteresis.
• Integrated inverters exhibited steep voltage transitions and high gain.

Conclusions:

• 2D LnOBr materials are promising wide-bandgap, high-κ dielectrics for next-generation 2D electronics.
• LaOBr offers a viable solution to leakage current issues, enabling high-performance and reliable 2D devices.
• This research expands the library of dielectric materials for innovative electronic applications.