Performance Limit of Ultrathin GaAs Transistors

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• High-electron-mobility group III-V compounds are leading candidates to replace silicon in advanced field-effect transistors (FETs).
• Gallium arsenide (GaAs) offers excellent n- and p-type device characteristics, making it a strong contender among III-V materials.
• Monolayer (ML) GaAs represents the thinnest possible form of GaAs, ideal for nanoscale electronic devices.

Purpose of the Study:

• To simulate and evaluate the performance of hydrogenated monolayer Gallium Arsenide (GaAsH2) metal-oxide-semiconductor field-effect transistors (MOSFETs).
• To assess the suitability of ML GaAsH2 as a channel material for next-generation electronics, particularly in the context of the International Technology Roadmap for Semiconductors (ITRS).
• To investigate the potential for complementary metal-oxide-semiconductor (CMOS) applications using ultrathin GaAs.

Main Methods:

• Ab initio quantum-transport simulations were employed to model the behavior of the GaAsH2 FETs.
• Device performance metrics including on-state current, delay time, power dissipation, and energy-delay product were analyzed.
• The impact of uniaxial compressive strain on p-type ML GaAsH2 MOSFETs was investigated.

Main Results:

• Both n- and p-type ML GaAsH2 MOSFETs demonstrated performance metrics that align with ITRS requirements for scaled gate lengths down to 3/4 nm (high-performance) and 3/5 nm (low-power).
• Ultrathin GaAs meets critical benchmarks for future electronic devices beyond the scope of Moore's Law scaling.
• Symmetrical performance was achieved between unstrained n-type and 2% uniaxially compressed p-type ML GaAsH2 MOSFETs.

Conclusions:

• Ultrathin GaAs, specifically hydrogenated monolayer GaAsH2, is a highly promising channel material for post-Moore era transistors.
• The simulated performance indicates that ML GaAsH2 can satisfy stringent requirements for both high-performance and low-power applications.
• The symmetrical performance of n- and p-type devices under specific conditions makes ultrathin GaAs suitable for advanced CMOS integrated circuits.