Thermal interface resistance: cross-over from nanoscale to macroscale

Abstract

In a recent work Gotsmann and Lantz have observed that the thermal interface conductivity for a nano-sized nominal contact area is proportional to the normal contact pressure in a wide pressure range, with a prefactor which is typically ∼103 higher than observed for the same materials at the macroscale. Here I discuss the cross-over from the nanoscale to the macroscale. I show that for macroscopic solids the spreading resistance will dominate the interfacial resistance in most cases.