Perspective on nanoheat generation and dissipation in semiconductor devices

In advanced microelectronics, heat originates within nanoscale transistor channels, where field-driven electrons accelerate and scatter before equilibrating with the lattice—forming highly localized hotspots. Heat then dissipates through mechanisms ranging from angstrom-scale phonon interactions to packaging-level conduction. Despite decades of efforts in chip thermal management, such as packaging-level cooling, the role of hot electrons at the root of nanoscale hotspot formation has remained insufficiently recognized. This perspective highlights recent advances in passive imaging of hot-electron dynamics in hotspot regions, revealing strong electron–lattice nonequilibrium (Te ∼ 103 K, far exceeding TL ∼ 300 K) and spatial decoupling that go beyond the classical Joule heating paradigm at the macroscale. This calls for a shift toward electron-focused thermal design at the individual transistor level. We outline emerging strategies to either suppress nanoheat generation (e.g., ΔTe ∼−50 K by evaporative cooling) or harness hot electrons to overcome thermal-equilibrium Boltzmann limits in post-Moore nanoelectronics.