Investigation of the Thermal Conductivity of Materials in 2D/3D Heterostructures

Abstract

Recent developments in nanofabrication have been enabling us to build 2D material-based devices with superior electrical, optical, and thermal properties. Just as with many other semiconductor devices heat generated within the device during operation may cause device degradation and reliability problems. In these devices, 2D and GaN or SiO2 materials are in contact due to fabrication or/and device requirements. Around these interfaces, thermal properties are strongly affected by the phonon scattering mechanisms in materials. Although thermal boundary conductance has been investigated more; despite its importance, the change in individual material thermal conductivities are not investigated in detail. To observe the changes in material thermal conductivities around the interfaces, heterostructures of common 2D materials: Mos2, WSe2, and h-BN on GaN and SiO2 substrates are simulated through nonequilibrium molecular dynamics (NEMD). Obtained thermal conductivities are later compared with the thermal conductivities of the isolated materials. These results shed light on the thermal transport mechanisms in 2D/GaN and 2D/SiO2 heterostructures and help to build better thermal management strategies for devices involving such architectures.