Determination of Thermal Conductivity of phase pure 10H-SiC Thin Films by non-destructive Raman Thermometry

TL;DR

This study uses non-destructive Raman thermometry to accurately measure the thermal conductivity of pure 10H-SiC thin films, validating the method's applicability at specific film thicknesses.

Contribution

It explores the limiting conditions of Raman thermometry for thin film thermal conductivity measurement and identifies the optimal film thickness for accurate results.

Findings

Thermal conductivity of 156 nm 10H-SiC film is 102.385 W/m·K.

The ideal film thickness for this measurement method is 156 nm.

The method's limiting conditions depend on film thickness and laser spot size.

Abstract

10 H SiC thin films are potential candidates for devices that can be used in high temperature and high radiation environment. Measurement of thermal conductivity of thin films by a non-invasive method is very useful for such device fabrication. Micro-Raman method serves as an important tool in this aspect and is known as Raman Thermometry. It utilises a steady-state heat transfer model in a semi-infinite half space and provides for an effective technique to measure thermal conductivity of films as a function of film thickness and laser spot size. This method has two limiting conditions i.e. thick film limit and thin film limit. The limiting conditions of this model was explored by simulating the model for different film thicknesses at constant laser spot size. 10H SiC films of three different thicknesses i.e. 104, 135 and 156 nm were chosen to validate the thin film limiting condition. It was found that the ideal thickness at which this method can be utilised for calculating thermal conductivity is 156 nm. Thermal conductivity of 156 nm film is found to be 102.385 $(Wm^{-1}K^{-1})$.