The Effects of Roughness, Temperature, and Near-Field Thermal Radiation on the Thermal Contact Resistance Between Dissimilar Materials Si, SiO2 and SiC
Abstract
Thermal contact resistance (TCR) can rein the overall thermal resistance when heat transfers at the interface of micro-nano system. This work has theoretically investigated the TCR between dissimilar typical materials (Si, SiO2 and SiC) in electronics. The effects of roughness, temperature and near-field radiation on the TCR are involved. Fractal-like random rough surfaces are constructed and the corresponding surface roughness power spectral densities (PSDs) are used as input to estimate the heat transfer across real contact regions. Radiation enhancement and roughness scattering effects are considered via performing calculations of fluctuational electrodynamics and proximity approximation. The results show that radiation is not a negligible term in the TCR for very smooth dielectric materials surfaces. For the room temperature (310 K/300 K) scenario of Si/SiO2 at a pressure of 1 MPa, the radiation contribution still accounts for 9% in the contact interface of two 5-nm-roughness surfaces. In the case of large temperature difference and other configuration, the contribution of radiation can exceed more than 20%. For increasingly miniaturized micro-electromechanical systems, it is necessary to consider the influence of near-field thermal radiation in the thermal management