Thermal Fatigue-Based Lifetime Prediction Method for Power Semiconductor Devices

Abstract:
Power semiconductor devices experience thermal fatigue from repetitive junction temperature cycling, critically impacting reliability. This paper presents an Arrhenius-based lifetime prediction methodology with temperature-dependent interpolation for arbitrary operating conditions. The method generates accurate lifetime curves from limited standard test data (PC1: Tvjmin=25deg C, PC2: Tvjmax=175deg C), overcoming conventional methods' limitations at intermediate temperatures. For complex temperature profiles typical of electric vehicle applications, the proposed method shows 3.5× improvement over conventional approaches that uniformly apply worst-case conditions. This enables optimized thermal management, reduced design margins, and enhanced reliability prediction for power electronic systems.