Transient thermal modeling of a nanoscale hot spot in multilayered film

Abstract

A subcontinuum based lattice Boltzmann method is used to accurately model the transient thermal response of a nanoscale hot spot in solids. We developed the numerical scheme for the hot spot in a thin uniform material and extended the approach to study the multilayered materials. We observed that subcontinuum effects of high temperature rise become more prominent as the size of the film reduces to the scale of carrier mean free path. The thermal transport through a double layer is also considered, both for constant temperature difference across the double layer and hot-spot generation in one of the layers, using the diffusive mismatch scattering model at the interface. A finite temperature jump is observed at the interface whose magnitude depends upon the dimensions and properties of the material on the either side of the interface. The insight into the nanoscale thermal modeling, acquired in this work via a relatively simple model, will be critical for the design and operation of complex data storage and electronic systems, dealing with subcontinuum systems.