A 65-nm SOTB implementation of a physically unclonable function and its performance improvement by body bias control

This study explores the feasibility of using silicon-on-thin-buried oxide (SOTB) devices for physically unclonable functions (PUFs) and the effect of body biasing of the SOTB on the performance of a PUF. The low variability of the SOTB is desirable for ultra-low-power operation of the circuit, whereas it can cause performance decrease in a PUF, because a PUF generates a unique chip ID by exploiting the device variability. This paper reports the feasibility of using a reduced-variability SOTB for a PUF for the first time. We fabricated arbiter PUFs in the 65-nm SOTB process and measured the PUF responses for core voltages in the range of 0.4-0.8 V and body bias in the range of -0.5-0.5 V. We demonstrated that the SOTB can be used to implement a PUF successfully, and its performance can be improved by adjusting the body bias of the SOTB.