Materials Discovery for Interconnects from First Principles

Modern transistor density on microchips requires nano-scale transistors, which necessitates the use of nano-scale wires. At this scale, traditional wires such as copper hinder performance due to a massive increase in resistance as the wire dimensions decrease. As shown previously, materials with Fermi velocities directed primarily along the direction of current can combat the resistivity scaling due to side-wall scattering[1]. We predict the resistivity scaling for thousands of materials utilizing machine learning (ML) models trained on the data from the previous study. For materials whose predicted resistivity scaling is competitive with copper, we validate the ML predictions using DFT. From there we compute electron-phonon interactions for candidates with competitive DFT-predicted resistivity scaling to estimate the resistivity as a function of dimension. We identify three materials with potential to outperform copper at dimensions less than 10 nanometers.

[1] S. Kumar, C. Multunas, B. Defay, D. Gall and R. Sundararaman, “Ultralow electron-surface scattering in nanoscale metals leveraging Fermi-surface anisotropy”, Phys. Rev. Mater. 6, 085002 (2022)