Thermal conduction across a boron nitride and silicon oxide interface

TL;DR

This study measures the interfacial thermal resistance between few-layer hexagonal boron nitride and silicon oxide, revealing how thickness and gaps affect heat conduction, which is crucial for nano/micro device thermal management.

Contribution

It provides the first detailed measurement of interfacial thermal resistance between h-BN and SiO2, highlighting the impact of voids and gaps on thermal conduction.

Findings

Interfacial thermal resistance is ~1.6×10^-8 m^2K/W for monolayer h-BN.

Interfacial thermal resistance increases to ~3.4×10^-8 m^2K/W for 12.8 nm-thick h-BN.

Voids and gaps limit thermal conduction at the interface.

Abstract

The needs for efficient heat removal and superior thermal conduction in nano/micro devices have triggered tremendous studies in low-dimensional materials with high thermal conductivity. Hexagonal boron nitride (h-BN) is believed to be one of the candidates for thermal management and heat dissipation due to its novel physical properties, i.e. thermal conductor and electrical insulator. Here we reported interfacial thermal resistance between few-layer h-BN and its silicon oxide substrate using differential 3 omega method. The measured interfacial thermal resistance is around ~1.6*10-8 m2K/W for monolayer h-BN and ~3.4*10-8 m2K/W for 12.8nm-thick h-BN in metal/h-BN/SiO2 interfaces. Our results suggest that the voids and gaps between substrate and thick h-BN flakes limit the interfacial thermal conduction. This work provides a deeper understanding of utilizing h-BN flake as lateral heat spreader in electronic and optoelectronic nano/micro devices with further miniaturization and integration.