A RISC-V 32-bit microprocessor based on two-dimensional semiconductors.

Area of Science:

• Materials Science
• Electrical Engineering
• Computer Engineering

Background:

• Conventional bulk semiconductors face limitations like drain-induced barrier lowering and restricted current on/off ratios.
• Two-dimensional (2D) semiconductors offer a promising alternative due to their atomic-layer thickness and unique electronic properties.
• Despite progress in 2D material growth and fabrication, integrating large numbers of transistors has remained a challenge.

Purpose of the Study:

• To demonstrate the feasibility of advanced integrated circuits using 2D semiconductor technology.
• To develop a functional microprocessor based on molybdenum disulfide (MoS2) transistors.
• To create a comprehensive standard cell library for 2D logic circuits.

Main Methods:

• Fabrication of a reduced instruction set computing architecture (RISC-V) microprocessor utilizing 5,900 MoS2 transistors.
• Development of a standard cell library comprising 25 types of logic units based on 2D semiconductor technology.
• Co-optimization of the manufacturing process flow and design for 2D logic circuits, mirroring silicon integrated circuit advancements.

Main Results:

• Successful execution of standard 32-bit instructions on the MoS2-based RISC-V microprocessor.
• Establishment of a complete standard cell library for 2D semiconductor technology.
• Overcoming significant challenges in wafer-scale integration of 2D circuits through a combined manufacturing and design methodology.

Conclusions:

• The developed MoS2 microprocessor prototype exemplifies the potential of 2D integrated-circuit technology as a successor to silicon.
• The integrated 2D logic circuits demonstrate a viable path towards high-performance, scalable electronic devices.
• This work overcomes critical hurdles in wafer-scale integration, enabling the next generation of advanced electronics.