An assembly made up of a micro-electro-mechanical system as physical unclonable function, which in reaction to a challenge, outputs a response in accordance with a mapping rule, and a controllable control element which is equipped, in accordance with a control command, to adjust an ambient parameter influencing the mapping rule.

A semiconductor device can include a first metal trace, a first via disposed on the first metal trace, a second metal trace disposed on the first via, and an insulator interposed between the first metal trace and the first via. The insulator can be configured to lower an energy barrier or redistribute structure defects or charge carriers, such that the first metal trace and the first via are electrically connected to each other when power is applied. The semiconductor device can further include a dummy via disposed on the first metal trace.