Multiscale thermal impact of BSPDN: SoC hotspot challenges and partial mitigation

Backside power delivery is a potent scaling booster but also carries concerns about self-heating implications. We discuss a multiscale thermal simulation framework that combines awareness of nanoscale transport and 3D geometry effects with accounting for long-range heat interactions across a full system. High-resolution analysis of an 80-core server SoC with realistic workload-based CPU heat inputs shows backside configurations carry up to 14 degrees penalty compared to conventional frontside counterparts. This accentuation of hotspots, caused by an interplay mechanism inside the layer stack assembly, can be mostly counteracted with a two-fold mitigation strategy.