Dual-Gate Carbon Nanotube Field Effect Transistors for Physically Unclonable Functional Applications

Abstract

In this study, we present a novel implementation of a physical unclonable function (PUF) using a carbon nanotube (CNT) network-based field-effect transistor (FET) with a lateral dual-gate structure. The lateral dual-gate CNT FET device leverages the inherent randomness of the CNT network formed during the deposition process, allowing for the generation of unique, unclonable encryption keys. By using dual independent gates, this device achieves a quaternary state implementation, enhancing security within the same device footprint compared with traditional binary bit PUFs. The randomness of the CNT network, combined with the dual-gate operation, allows for the extraction of different threshold voltage (VT) from a single transistor, which are then used to classify four distinct states, further improving security. PUF performance indicators, such as the interchip Hamming distance and uniformity, were evaluated, and both indicators were found to be close to the ideal value of 50%. This study demonstrates that CNT-based PUF devices, particularly those employing dual-gate architectures, provide a scalable and secure solution for hardware encryption applications, offering superior performance compared to their single-gate counterparts. © 2025 American Chemical Society.