Approximating the age of RF/analog circuits through re-characterization and statistical estimation

Counterfeit ICs have become an issue for semiconductor manufacturers due to impacts on their reputation and lost revenue. Counterfeit ICs are either products that are intentionally mislabeled or legitimate products that are extracted from electronic waste. The former is easier to detect whereas the latter is harder since they are identical to new devices but display degraded performance due to environmental and use stress conditions. Detecting counterfeit ICs that are extracted from electronic waste requires an approach that can approximate the age of manufactured devices based on their parameters. In this paper, we present a methodology that uses information on both fresh and aged ICs and tries to distinguish between the fresh and aged population based on an estimate of the age. Since analog devices age mainly due to their bias stress, input signals play less of a role. Hence, it is possible to use simulation models to approximate the aging process, which would give us access to a large population of aged devices. Using this information, we can construct a statistical model that approximates the age of a given circuit. We use a Low noise amplifier (LNA) and an NMOS LC oscillator to demonstrate that individual aged devices can be accurately classified using the proposed method.