Low-Thermal-Budget Ferroelectric Field-Effect Transistors Based on CuInP2S6 and InZnO

TL;DR

This paper presents low-thermal-budget ferroelectric FETs using 2D CuInP2S6 and InZnO, demonstrating non-volatile memory, synaptic functionalities, and integration potential for energy-efficient neural networks.

Contribution

Introduction of low-thermal-budget ferroelectric FeFETs based on CuInP2S6 and InZnO with applications in memory and neuromorphic computing.

Findings

Non-volatile memory window of ~1 V

Stable multi-level synaptic states with ratio 125

Over 80% accuracy in MNIST digit recognition

Abstract

In this paper, we demonstrate low-thermal-budget ferroelectric field-effect transistors (FeFETs) based on two-dimensional ferroelectric CuInP2S6 (CIPS) and oxide semiconductor InZnO (IZO). The CIPS/IZO FeFETs exhibit non-volatile memory windows of ~1 V, low off-state drain currents, and high carrier mobilities. The ferroelectric CIPS layer serves a dual purpose by providing electrostatic doping in IZO and acting as a passivation layer for the IZO channel. We also investigate the CIPS/IZO FeFETs as artificial synaptic devices for neural networks. The CIPS/IZO synapse demonstrates a sizeable dynamic ratio (125) and maintains stable multi-level states. Neural networks based on CIPS/IZO FeFETs achieve an accuracy rate of over 80% in recognizing MNIST handwritten digits. These ferroelectric transistors can be vertically stacked on silicon CMOS with a low thermal budget, offering broad applications in CMOS+X technologies and energy-efficient 3D neural networks.