Ultimate optimization of interface thermal resistance by utilizing interfacial nonlinear interaction

Abstract Decreasing interface thermal resistance (ITR or Kapitza resistance) is the key to solve the problem of heat dissipation in integrated circuits, which are the core elements for electronics. In this paper, interfacial nonlinear interaction is introduced to optimize ITR. Interestingly, it is found that the optimized ITR by introducing interfacial nonlinear interaction can be greatly decreased compared to the case optimized solely with interfacial linear interaction. A 51.2% reduction in ITR is achieved in a weak anharmonic system. The mechanism behind this is attributed to the expansion of inelastic channels and the decrease of mismatch for nonlinear coefficients which are verified by spectral analysis. The relationship of optimized interfacial nonlinear coefficient and interfacial linear coefficient k 12 can be approximately predicted by the self-consistent phonon theory. The studies here emphasize the importance of mutual controlling interfacial linear and nonlinear interactions for further decreasing ITR.