Tuning the thermal conductivity of silicon carbide by twin boundary: A molecular dynamics study

Silicon carbide (SiC) is a semiconductor with excellent mechanical and physical properties. We study the thermal transport in SiC by using non-equilibrium molecular dynamics simulations. The work is focused on the effects of twin boundaries and temperature on the thermal conductivity of 3C-SiC. We find that compared to perfect SiC, twinned SiC has a markedly reduced thermal conductivity when the twin boundary spacing is less than 100 nm. The Si-Si twin boundary is more effective to phonon scattering than the C-C twin boundary. We also find that the phonon scattering effect of twin boundary decreases with increasing temperature. Our findings provide insights into the thermal management of SiC-based electronic devices and thermoelectric applications.