Analytical models for mean free path and resistivity of borophene for on-chip interconnects

Scaling copper interconnects below the 7-nm technology node results in severe resistivity increase due to enhanced electron scattering, necessitating alternative interconnect materials. This work proposes borophene nanoribbons (BNRs) and presents a novel analytical models to evaluate their intrinsic mean free path (MFP), resistance, and effective resistivity under ideal smooth-surface conditions. The model captures quantum transport effects and Fermi-energy-dependent conduction channels for armchair and zigzag BNRs and is benchmarked against graphene and copper. At the 7-nm node and a Fermi energy of 0.3 eV, borophene exhibits an intrinsic MFP comparable to graphene and nearly three orders of magnitude higher than copper. Additionally, borophene achieves up to an 85.5% reduction in effective resistivity compared to copper, while maintaining competitive performance relative to graphene. These findings demonstrate that Fermi-energy tuning significantly enhances borophene’s transport performance, highlighting its strong potential as a scalable and energy-efficient on-chip interconnect material for advanced CMOS technologies.