A Universal Scaling Formulation of the Generalized Peck’s Equation for Corrosion Limited Lifetime in Self-Heated ICs

Since the early 1980s, the highly accelerated stress test in conjunction with conventional temperature–humidity–bias testing has been the industry-standard method for interpreting relative humidity (RH) and temperature (
$T$
)-dependent failure modes in nonhermetically packaged ICs, solar modules, and other electronic components. In recent years, however, testing requirements based on JEDEC standards and the corresponding lifetime extrapolation to end-use conditions using Peck’s equation have been criticized as overly conservative for modern self-heated logic/power ICs. In practice, the self-heated ICs correlate RH and
$T$
in a way that is not explicitly accounted for by Peck’s equation. In this study, we investigate the IC lifetime due to electrochemical failures—Cu–Al bond wire corrosion—by considering the effects of ambient RH,
$T$
, duty cycle, and self-heating temperature rise using an integrated self-consistent finite element-based Multiphysics model and propose a generalized Peck’s equation for self-heated ICs. Our study reveals how the asymmetry between ON and OFF-state heating leads to dramatic suppression of the effective RH experienced by an integrated circuit and, most importantly, identifies that the corrosion of Cu–Al bond wire occurs in spikes during the ON–OFF transition when both RH and
$T$
are high. The generalized Peck’s equation also predicts an elegant scaling relationship among the fundamental variables associated with a self-heated IC lifetime. The prediction is validated by experimental lifetime data from self-heated IC published in the literature. The experimental validation of the physics-informed generalized Peck’s equation suggests the possibility of more accurate (and optimistic) lifetime predictions of modern ICs and solar modules.