Work

An IGZO phototransistor-based ternary inverter integrating optical sensing and weight quantization in ternary neural networks for color image recognition

Year: 2026

Type: article

Abstract: As deep neural networks (DNNs) continue to advance computer vision, natural language processing, and medical diagnostics, their reliance on 32-bit full-precision weights imposes substantial model size and computational burdens that hinder deployment at the edge; to improve efficiency, we adopt ternary neural networks (TNNs). Here, we present a ternary circuit composed of two parallel indium-gallium-zinc-oxide (IGZO) thin-film phototransistors (TFPTs) and a resistor, exhibiting three stable, discrete current states 'OFF', 'Intermediate', and 'ON' that map to the ternary weight set {-1, 0, 1}; we further realize a compact ternary inverter using only two IGZO TFPTs and two resistors, avoiding complex binary CMOS logic. The processing path begins with optical sensing, wherein the incident light power densities and wavelength determine discrete voltage outputs; during preprocessing, these voltages discretize pixel values (0-255) into multiple intervals that are supplied to the TNN for image recognition. Leveraging this integrated sensing, preprocessing and inference hardware module, we achieve >90% accuracy on CIFAR-10, thereby validating device-level data discretization and transformation and charting a path toward integrated neuromorphic vision systems.

Source: Nanoscale Horizons

DOI: 10.1039/d5nh00720h

Authors: Wun-Yun Lin, Yong-Yi Huang, Yu-Chieh Chen, Chen-Gang Jang, Li-Chung Shih, Jen-Sue Chen

Institution: National Cheng Kung University

Language: English

Topic: Advanced Memory and Neural Computing

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Funders: National Science and Technology Council, National Science and Technology Council

Awards: Y2o3-Based Memristors: from Model Devices and Arrays toward Predictive Synaptic Computing, G4987410269, Key Materials and Dynamic Electronic Characteristics of Volatile Memristors for Ai Chips( III ), Short-Term Synaptic Plasticity in Oxide Phototransistors for Temporal Data Processing in Neuromorphic Computing, Applications of Light-Adaptive Oxide Transistors in Bionic Vi Sual Systems and In-Sensor Computing