Exploring Unconventional Resistivity Scaling in Topological Semimetals for Interconnects Beyond Copper
Due to surface and disorder scattering, the polynomial increase in resistivity of conventional metals with shrinking dimensions severely impacts the performance of highly scaled integrated circuits. Here we explore a new class of materials – topological semimetals – as an alternative solution. We demonstrate that, through conduction of the topological surface states, the resistivity in topological semimetals reduces with decreasing feature size in the nanometer scale, even in the presence of defects and grain-boundary scattering. This sharply contrasts the scaling of conventional metals, such as Cu. In this talk, we will present first-principles calculation results of a representative Si-CMOS compatible topological semimetal CoSi, and report experimental evidence for surface-dominated transport in CoSi thin films, showing resistivity below that of the bulk single-crystals. Our proof-of-principle studies demonstrate the potential of topological semimetal interconnects. We will conclude with a set of the guidelines for screening topological semimetals for such applications.