Device of physically unclonable function with floating gate transistors, and manufacturing method

Abstract

In accordance with an embodiment, a physically unclonable function device includes a set of floating gate transistor pairs, floating gate transistors of the set of floating gate transistor pairs having a randomly distributed effective threshold voltage belonging to a common random distribution; a differential read circuit configured to measure a threshold difference between the effective threshold voltages of floating gate transistors of floating gate transistor pairs of the set of floating gate transistor pairs, and to identify a floating gate transistor pair in which the measured threshold difference is smaller than a margin value as being an unreliable floating gate transistor pair; and a write circuit configured to shift the effective threshold voltage of a floating gate transistor of the unreliable floating gate transistor pair to be inside the common random distribution.