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arXiv · 1805.01517

Enhanced Electron Transport in Thin Copper Films via Atomic-Layer Materials Capping

Abstract

Using first-principles calculations based on density functional theory and non-equilibrium Green's functions, we characterized the effect of surface termination on the electronic transport properties of nanoscale Cu slabs. With ideal, clean (111) surfaces and oxidized ones as baselines we explore the effect of capping the slabs with graphene, hexagonal boron nitrate, molybdenum disulfide and stanene. Surface oxide suppresses balistic conductance by a factor of 10 compared to the ideal surface. Capping the ideal copper surface with graphene slightly increase conductance but MoS$_2$ and stanene have the opposite effect due to stronger interactions at the interface. Interestingly, we find that capping atomistically roughed copper surfaces with graphene or MoS$_2$ decreases the resistance per unit length by 20 and 13%, respectively, due to reduced scattering. The results presented in this work suggest that two-dimensional materials can be used as an ultra-thin liner in metallic interconnect technology without increasing the interconnect line resistivity significantly.

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BibTeXRIS

David M. Guzman, Alejandro Strachan. 2018-05-03. Enhanced Electron Transport in Thin Copper Films via Atomic-Layer Materials Capping. https://arxiv.org/abs/1805.01517

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