10.1021/acsnano.7b06658.s001 Kyu-Man Hwang Kyu-Man Hwang Jun-Young Park Jun-Young Park Hagyoul Bae Hagyoul Bae Seung-Wook Lee Seung-Wook Lee Choong-Ki Kim Choong-Ki Kim Myungsoo Seo Myungsoo Seo Hwon Im Hwon Im Do-Hyun Kim Do-Hyun Kim Seong-Yeon Kim Seong-Yeon Kim Geon-Beom Lee Geon-Beom Lee Yang-Kyu Choi Yang-Kyu Choi Nano-electromechanical Switch Based on a Physical Unclonable Function for Highly Robust and Stable Performance in Harsh Environments American Chemical Society 2017 NEM-switch-based PUF van der Waals forces PUF device PUF performance Nano-electromechanical Switch NEM switch HD dose radiation nano-electromechanical system stiction Harsh Environments interchip Hamming distance MEMS stress tests unclonable function response bit-string Physical Unclonable Function hardware-based security Stable Performance 2017-12-13 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Nano-electromechanical_Switch_Based_on_a_Physical_Unclonable_Function_for_Highly_Robust_and_Stable_Performance_in_Harsh_Environments/5697403 A physical unclonable function (PUF) device using a nano-electromechanical (NEM) switch was demonstrated. The most important feature of the NEM-switch-based PUF is its use of stiction. Stiction is one of the chronic problems associated with micro- and nano-electromechanical system (MEMS/NEMS) devices; however, here, it was utilized to intentionally implement a PUF for hardware-based security. The stiction is caused by capillary and van der Waals forces, producing strong adhesion, which can be utilized to design a highly robust and stable PUF. The probability that stiction will occur on either of two gates in the NEM switch is the same, and consequently, the occurrence of the stiction is random and unique, which is critical to its PUF performance. This uniqueness was evaluated by measuring the interchip Hamming distance (interchip HD), which characterizes how different responses are made when the same challenge is applied. Uniformity was also evaluated by the proportion of “1” or “0” in the response bit-string. The reliability of the proposed PUF device was assessed by stress tests under harsh environments such as high temperature, high dose radiation, and microwaves.