Hardware-based security devices using a physical unclonable function created by the irregular grain boundaries found in perovskite calcium titanate.

The IoT era necessitated the need for hardware-based security devices due to their strong resistance to hacking compared to software-based systems, which are limited by CPU usage and performance. Hardware-based systems are more unpredictable due to their unique and non-discernible external properties. This research focused on developing a security device based on lead-free metal oxide CaTiO 3 perovskite material with irregular electrical characteristics, known as physical unclonable functions. These irregularities were created by increasing the number of grain boundaries on the device surface through high-temperature annealing, resulting in greater adsorbed oxygen. The outcome was a highly random and unique security key using irregular electrical characteristics with 49.53% uniformity and a 46.55% inter-Hamming distance. • A lead-free CaTiO 3 perovskite material leads to physically unclonable functions. • The irregularities produced by the formation of grain boundaries and oxygen vacancies. • A CaTiO 3 film was investigated by AFM, SEM, XRD, UV–vis, FT-IR, and XPS. • Security keys were achieved with a 49.53% uniformity and a 46.55% inter-HD. [ABSTRACT FROM AUTHOR]