Broadly manipulating the interfacial thermal energy transport across the Si/4H-SiC interfaces via nanopatterns

Manipulating the thermal transport across the interfaces via nanostructuring is critical for thermal man-agement in electronics and energy conversion in thermoelectrics. Recent experiments have enabled the fabrication of controllable nanopatterns at interfaces, and therefore provide a new perspective to design and manipulate interfacial heat transfer. By performing nonequilibrium molecular dynamics simulations, we reported that the interfacial thermal conductance of Si/4H-SiC interfaces can be modulated broadly from similar to 300 MW/m(2)K to similar to 10 0 0 MW/m(2)K by confining nanopatterns with a thickness on the order of nanometers, i.e., smaller than 30 nm. Based on the spectral heat current and participation ratio analysis, the nonmonotonic nanopattern section-dependent thermal conductance as observed in our simulations was found to be originated from two competing mechanisms, i.e., phonon-boundary scattering and inter -facial phonon transport channels. The corresponding interfacial thermal conductance initially decreased with the nanopattern section when the phonon-boundary scattering is dominant and became stronger, and then increased when there were many more possible interfacial phonons transport channels. The thermal conductance was enhanced by similar to 11% compared to that of the bare Si/4H-SiC interface once the latter mechanism was dominant. Besides, the thermal resistance induced by the pattern itself becomes evident and must be considered when the height of the nanopattern becomes greater. Our work here provides a comprehensive investigation on manipulating the thermal transport across the interfaces via controllable nanopatterns, which is important and meaningful for designing and optimizing the advanced thermal interface materials. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Manipulating thermal transport across interfaces using nanostructures is crucial for thermal management in electronics and energy conversion. Recent experiments have shown that controllable nanopatterns can modulate the interfacial thermal conductance. Non-equilibrium molecular dynamics simulations revealed that the thermal conductance of Si/4H-SiC interfaces can be manipulated by confining nanopatterns with a thickness smaller than 30 nm. This modulation arises from competing mechanisms of phonon-boundary scattering and interfacial phonon transport channels. The study provides insights into the design and optimization of advanced thermal interface materials.