Extending Die-Attachment Fatigue Life of Power Electronics Using Phase Change Materials
The ever-increasing power throughput and ever-decreasing size of modern electronics, specifically power electronics, requires more advanced packaging techniques and materials to maintain thermal limits and sustain mechanical life. Specific applications with known operating conditions for these components can realize added benefits through a tailored thermal-mechanical-electrical optimized assembly, potentially utilizing niche material classes. Without losing any expected functionality, solid-liquid phase change materials could be incorporated into the device structure to reduce peak temperature and/or suppress high-cycle fatigue problems commonly found at die-attachment interfaces. The purpose of this study was to investigate, through model-based design and analysis, the impact of using organic phase-change materials (PCMs) at two strategic locations in the standard device stack. The results suggest noteworthy life improvement (40%) is possible when optimizing for a given melt point material. Additionally, further improvements were predicted through future material enhancements, namely thermal conductivity and latent heat.