This article describes a previously unreported single-event radiation effect in spiral inductors manufactured in a commercial CMOS technology when subjected to ionizing radiation. Inductors play a major role as the component determining the frequency of LC tank oscillators, which is why any radiation effects in these passive components can have detrimental impact on the performance of clock generation circuits. Different experiments performed to localize and characterize the Single-Event Effect (SEE) response in a radiation-hardened PLL circuit are discussed and presented together with an hypothesis for the underlying physical mechanism.
