Nanoscale interconnects for future semiconductors from first principles*

Resistance in nanoscale wires is increasingly the main bottleneck in the performance of semiconductor computing devices. With reducing dimensions, scattering of electrons at surfaces, interfaces and grain boundaries increases rapidly and causes a sharp increase of resistivity of conventional metals at the nano scale compared to bulk. We use first-principles calculations of ballistic electron transport and electron-phonon scattering to explore several complementary strategies to reduce resistance at nanoscale dimensions. We investigate strategies ranging from maximizing ballistic conductance of conventional metals, to the possibility of topological protection in surface-state conduction. We identify anisotropy and directionality of electronic states in metals as a promising way to mitigate surface scattering. From high-throughput electronic structure calculations of thousands of known intermetallics and metallic compounds, we propose promising directional metals for narrow interconnects in future computing devices.