2D Materials-Based Static Random-Access Memory.

Area of Science:

• Materials Science
• Semiconductor Physics
• Nanotechnology

Background:

• 2D transition-metal dichalcogenide (TMD) semiconductors possess suitable bandgaps for advanced logic transistors.
• Scaling down transistors necessitates exploring novel channel materials beyond silicon.

Purpose of the Study:

• To investigate the scalability of 2D material (2DM)-based field-effect transistor (FET) and static random-access memory (SRAM) cells.
• To analyze the impact of layer thickness on 2DM FET and SRAM performance.
• To explore the potential of 2DM nanosheet (NS) gate-all-around (GAA) structures for future semiconductor technology.

Main Methods:

• Simulations were conducted to study the scalability of 2DM FETs and SRAM cells.
• The impact of layer thickness (monolayer, bilayer, trilayer) on device performance was analyzed.
• The integration of nanosheet (NS) gate-all-around (GAA) structures with 2DMs was simulated.

Main Results:

• Monolayer 2DM FETs exhibit superior electrostatics, mitigating read-write conflicts in SRAM cells at scaled nodes (1-2.1 nm).
• Monolayer 2DM SRAM cells show reduced read access and write times compared to thicker layers at fixed leakage power.
• Optimized 2DM SRAM with advanced parameters demonstrates excellent stability and speed at the 1-nm node.
• 2DM NS-GAA structures improve SRAM cell density and reduce access/write times, indicating a viable scaling path beyond silicon.

Conclusions:

• Monolayer 2DMs are promising for ultrascaled logic transistors and SRAM cells.
• 2DM NS-GAA FETs offer a feasible route for semiconductor scaling beyond current silicon technology.
• Process challenges for 2DM NSFET fabrication, including layer stacking and contact formation, require further investigation.