A Thermodynamic Framework for Reliability Kinetics

Area of Science:

• Materials Science
• Physics
• Chemical Engineering

Background:

• Power-law relationships are crucial for modeling degradation kinetics and predicting device lifetime in reliability physics.
• These relationships apply to diverse failure mechanisms like time-dependent dielectric breakdown (TDDB), hot-carrier injection (HCI), bias temperature instability (BTI), electromigration (EM), and fatigue.

Purpose of the Study:

• To develop a unified thermodynamic framework for reliability kinetics.
• To generalize kinetic equations by incorporating thermal activation, stress acceleration, and accumulated degradation.
• To introduce novel parameters quantifying stress influence and degradation correlation.

Main Methods:

• Derivation of a generalized kinetic equation from Gibbs free energy and entropy partitioning.
• Introduction of a stress coefficient (γ) and a correlation coefficient (χ).
• Interpretation of established reliability mechanisms within the new thermodynamic framework.

Main Results:

• The framework successfully explains empirical power-law degradation kinetics.
• TDDB shows independent evolution, HCI exhibits weak self-limiting behavior, BTI shows strong self-limiting behavior, and fatigue demonstrates self-amplifying behavior.
• Electromigration highlights the role of stress acceleration (γ).

Conclusions:

• The proposed thermodynamic framework offers a unified interpretation of degradation kinetics.
• Degradation correlation (χ) is identified as a key descriptor for enhanced reliability modeling and lifetime prediction.
• This approach provides a more comprehensive understanding of material degradation under stress.