Few-layer Phosphorene: An Ideal 2D Material For Tunnel Transistors

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanoelectronics

Background:

• Atomically thin 2D transition metal dichalcogenides (TMDs) are explored for energy-efficient tunneling field-effect transistors (TFETs) due to superior gate control.
• However, most TMDs possess bandgaps (Eg) and effective masses (m(*)) unsuitable for optimal TFET performance.

Purpose of the Study:

• To investigate few-layer phosphorene as a novel 2D material for high-performance TFET applications.
• To evaluate phosphorene's suitability for next-generation, energy-efficient electronic devices.

Main Methods:

• Utilized full-band atomistic quantum transport simulations.
• Analyzed key material properties including direct bandgap, light and anisotropic effective mass, and mobility.
• Simulated TFET performance metrics such as ON/OFF current ratio and energy-delay products.

Main Results:

• Phosphorene exhibits a direct bandgap (~1.0-0.4 eV), light effective mass (~0.15 m0), anisotropic effective mass, and high mobility, ideal for TFETs.
• Phosphorene TFETs achieve high ON currents (~1 mA/um) and ON/OFF ratios (~10^6) at a 15 nm channel length and 0.5 V supply voltage.
• Demonstrated scalability down to 6 nm channel length and 0.2 V supply voltage with acceptable performance.

Conclusions:

• Few-layer phosphorene possesses optimal electronic properties for advanced TFETs.
• Phosphorene TFETs significantly outperform state-of-the-art TMD-TFETs and CMOS devices in key performance metrics.
• Phosphorene is a strong candidate for developing energy-efficient and scalable replacements for traditional MOSFETs.