Interface thermal resistance modeling of the silicon-argon interface

Abstract

Advancements in nanoscale precision engineering require an in-depth understanding of energy transport. The thermal properties of fluids containing nano-particles significantly depend on the particle/fluid volume ratio at high interface thermal resistance lengths (Kapitza lengths). However, there is a lack of fundamental understanding of nano-scale thermal transport based on the continuum mechanics. In nano-scale thermal transport, the molecular structure of the liquid and surfaces and their interactions on atomic length scales are indispensable. In this study, a molecular level investigation of the thermal resistance at the silicon-argon interface is implemented using molecular dynamics (MD) simulations. This research investigates the interface thermal resistance between liquid argon and silicon surfaces with a perfect crystalline structure. Silicon and argon are chosen due to their broad use in nano-technology applications. Layering of argon liquid molecules on the silicon solid interface was evident for weak wall/fluid interaction strength and bin sizes smaller than the molecular diameter. A recently developed interface thermal resistance (Kapitza resistance) model is used in this study (Kim et al., Journal of Chemical Physics, 129, 174701, 2008). Interactive thermal wall (ITW) model can significantly reduce the computational cost for silicon crystal walls. However, the ITW model needs to properly model thermal interactions with argon molecules using modified liquid/solid interaction strength and thermal oscillation frequency. Our simulation result matches with the case for the ITW model for the similar liquid/solid interaction strength.