Non-Volatile Reconfigurable Four-Mode van der Waals Transistors and Transformable Logic Circuits

Area of Science:

• Materials Science
• Electrical Engineering
• Computer Engineering

Background:

• Emerging applications require logic circuits with high functional density, reconfigurability, and energy efficiency.
• Existing technologies face limitations in achieving these combined functionalities.

Purpose of the Study:

• To demonstrate novel nonvolatile reconfigurable four-mode field-effect transistors (NVR4M-FETs).
• To explore the potential of NVR4M-FETs for advanced computing and secure hardware applications.

Main Methods:

• Fabrication of NVR4M-FETs using two-dimensional (2D) MoTe2 and CuInP2S6 (CIPS).
• Exploitation of CIPS ferroelectric polarization for dynamic transistor polarity switching (n-type and p-type).
• Integration of multilayer graphene floating gates for threshold voltage modulation, enabling four distinct nonvolatile operating modes.

Main Results:

• Achieved transistors with four distinct nonvolatile operating modes: n-type logic, p-type logic, always-on memory, and always-off memory.
• Demonstrated NVR4M-FETs as one-transistor-per-bit ternary content-addressable memory (TCAM).
• Constructed transformable logic gates (14 functions) and a reconfigurable half adder/subtractor.
• Showcased a 2-input look-up table using 8 NVR4M-FETs, outperforming conventional reconfigurable transistors.

Conclusions:

• NVR4M-FETs offer a promising platform for high-density, energy-efficient logic circuits.
• These devices are suitable for in-memory computing and secure hardware applications.
• The demonstrated four-mode functionality significantly enhances circuit design flexibility and performance.