학술논문
Physically Unclonable Function With a Rough Silicon Channel MOSFET
Document Type
Periodical
Author
Source
IEEE Transactions on Electron Devices IEEE Trans. Electron Devices Electron Devices, IEEE Transactions on. 71(1):425-430 Jan, 2024
Subject
Language
ISSN
0018-9383
1557-9646
1557-9646
Abstract
To achieve a physical unclonable function (PUF) in a MOSFET, variations in the threshold voltage ( ${V}_{\text {T}}$ ) were intentionally induced by engineering surface roughness in a silicon channel through wet etching. The roughened surface produces fluctuations in gate oxide thickness and variability in crystal orientation, deviating from the (100) surface with a large number of interface traps. This results in a variation in ${V}_{\text {T}}$ . A binary bit state was encoded by using a high or low ${V}_{\text {T}}$ in each MOSFET, representing a “0” or “1” state. Three representative PUF metrics, namely uniformity, interchip Hamming distance (HDinter), and intrachip Hamming distance (HDintra), were evaluated. PUF keys with intentionally produced random surface roughness exhibited nearly ideal PUF metric values, even after a lapse of 300 days without any passivation for device protection.