Assessing uniqueness and reliability of SRAM-based Physical Unclonable Functions from silicon measurements in 45-nm bulk CMOS

Assessments of the uniqueness and reliability for SRAM-based Physical Unclonable Functions (PUFs) embedded in dies were conducted using silicon measurements. To generate an intrinsic identification (ID) for each die, embedded SRAM PUFs of three types were implemented using 45-nm bulk CMOS technology: 1) single power-on scheme, 2) divided-power-on scheme, and 3) low/low writing scheme. Measured Hamming distances of IDs between 64 dies showed no significant advantage or disadvantage in three SRAM-based PUFs in terms of uniqueness, being acceptable for practical use. The measured error rates of IDs in iteration, supply voltage variation, and temperature variation show that the divided-power-on scheme has better reliability than the other schemes.