Advanced 2.5D and 3D heterogeneous AI chiplet packages have crossed a threshold where thermal management is a co-design challenge spanning architecture, packaging, and system-level optimization simultaneously. Chiplet partitioning sets the thermal envelope that packaging must manage; packaging architecture determines what simulation can predict; system-level power management shapes what the package must survive. No single team owns this problem, and no single methodology addresses it. Three forces have converged: simulation methods embedded in placement flows lose structural validity at manufacturing-resolution 2.5D/3D geometries—not merely precision; packaging innovation is moving faster than the tools that model its thermal implications; and system-level thermal optimization remains disconnected from the package co-design loop. This panel convenes experts across simulation, advanced packaging architecture, production AI thermal design, and system-level optimization to debate the path forward. Three positions structure the discussion: simulation first—physics-intelligence simulation is the missing link for fast, accurate thermal and warpage prediction at physical dimensions; packaging innovation first—advanced interposers, embedded thermal structures, and chiplet-aware stacking can reduce the thermal problem before simulation must solve it; and system-level ownership first—thermal co-design spans chip architects, package engineers, system designers, and foundry partners, requiring a closed-loop workflow so improvements propagate across every layer.
