A team from UCLA’s Samueli School of Engineering, working with researchers at Argonne National Laboratory and other institutions, has identified a metallic material with the highest thermal conductivity ever measured among metals.
The material, theta-phase tantalum nitride (theta-TaN), achieves a thermal conductivity of approximately 1,100 W/m-K — nearly triple that of copper at roughly 400 W/m-K and far ahead of aluminum’s 167 to 237 W/m-K range.
Heat transport in metals depends on both free-moving electrons and atomic vibrations known as phonons. In most metals, strong electron-phonon interactions limit how efficiently heat can flow. Theta-TaN’s unique hexagonal atomic structure, with tantalum atoms interspersed with nitrogen, suppresses these interactions and allows heat to move far more freely.
The team confirmed the material’s performance using multiple advanced techniques, including synchrotron-based X-ray scattering and ultrafast optical spectroscopy at Argonne’s recently upgraded Advanced Photon Source.
The discovery has immediate implications for semiconductor thermal management. As chip power densities continue to rise with each new process node, effective heat dissipation has become one of the most critical design constraints. Theta-TaN could enable thinner, more efficient heat spreaders and heat sinks for high-performance computing, AI accelerators, and power electronics.
The researchers caution that commercial adoption will require solving integration challenges, including deposition methods compatible with existing semiconductor manufacturing processes.
