Length dependent thermal conductivity of silicon and copper nanowire: a molecular dynamics study

Abstract

The miniaturization and higher power density of modern electronics pose a significant challenge in thermal management. A key focus in addressing this challenge revolves around the advancement of thermal interfaces within microchip packaging, aiming to enhance thermal energy dissipation and optimization of performance. Copper nanowires are extensively employed in the chip industry as interconnects for signal transmission and thermal management purposes. Investigating the impact of reduced cross-section on the thermal transport properties of nanowires is crucial. In this study, the thermal conductivity of copper and silicon nanowires is studied with variations in the length of the nanowires. The simulation is conducted with the Equilibrium Molecular Dynamics (EMD) process. The cross-section of the nanowire is kept fixed (10 × 10 nm) and with the increase in length, its thermal conductivity is studied. At room temperature for a 50 nm length, the lattice thermal conductivity value is 1.68 and 0.037 W m − 1 K − 1 for silicon and copper nanowires, respectively. We further studied the phonon scattering, mean free path, and group velocity of silicon and copper lattices. Our study may help to design more thermally efficient microchips and innovate new cooling methods of microelectronics.