Organic Current Mirror PUF for Improved Stability Against Device Aging
Zhaoxing Qin, Michihiro Shintani, Kazunori Kuribara, Yasuhiro Ogasahara, Takashi G. Sato · IEEE Sensors Journal · 2020
Physically unclonable functions (PUFs) are important primitives in the field of hardware security. Their applications can be further broadened if PUFs are fabricated using organic thin-film transistors (OTFTs). Examples include smart packaging that proves authenticity of a contained product and privacy protection for information gathered by organic sensors. This paper proposes an organic current mirror PUF (OCM-PUF) that can be fabricated on a flexible substrate. The proposed OCM-PUF adapts a current mirror structure to achieve self-compensation of the device performance degradation of OTFTs, which is unavoidable in most organic materials. Two types of OCM-PUFs were designed using a low supply voltage OTFT to evaluate the metrics as a PUF. The fabricated OCM-PUFs maintained a reliability of nearly 95% over few weeks, thereby showing that the proposed PUF achieved a high tolerance against response changes caused by device aging.