Highly Reliable Physical Unclonable Function Based on ZnO-SnO2 Gas Sensor

To address the problems of resource limitation and vulnerability of internet of things (IoT) sensing nodes, a highly reliable physical unclonable function (PUF) design scheme is proposed by analyzing the characteristics of ZnO-SnO 2 gas sensor preparation, the response mechanism of the PUF, and noise suppression methods. In the proposed scheme, first, the gas sensors are prepared using ZnO-SnO 2 nanofibers. then the gas response data is collected at different gas concentrations, and the operating voltages are obtained using ZnO-SnO 2 gas sensors. Further, 128-bit PUF responses are generated by combining the median value averaging filtering method and a multi-bit balancing algorithm. Finally, the safety and reliability of the designed PUF is evaluated. The experimental results showed that the PUF uniqueness of this gas sensor was 50.93%, randomness was 97.92%, and reliability was 98.05%.