Theoretical analysis of thermal boundary conductance of MoS₂-SiO₂and WS₂-SiO₂interface

Understanding the physical processes involved in interfacial heat transfer is critical for the interpretation of thermometric measurements and the optimization of heat dissipation in nanoelectronic devices that are based on transition metal dichalcogenide (TMD) semiconductors. We model the phononic and electronic contributions to the thermal boundary conductance (TBC) variability for the MoS₂-SiO₂and WS₂-SiO₂interface. A phenomenological theory to model diffuse phonon transport at disordered interfaces is introduced and yieldsG= 13.5 and 12.4 MW/K/m²at 300 K for the MoS₂-SiO₂and WS₂-SiO₂interface, respectively. We compare its predictions to those of the coherent phonon model and find that the former fits the MoS₂-SiO₂data from experiments and simulations significantly better. Our analysis suggests that heat dissipation at the TMD-SiO₂interface is dominated by phonons scattered diffusely by the rough interface although the electronic TBC contribution can be significant even at low electron densities (n= 10¹²cm^-2) and may explain some of the variation in the experimental TBC data from the literature. The physical insights from our study can be useful for the development of thermally aware designs in TMD-based nanoelectronics.