Raman micro-spectroscopy as a tool to measure the absorption coefficient and the erosion rate of hydrogenated amorphous carbon films heat-treated under hydrogen bombardment

TL;DR

This paper introduces a rapid Raman micro-spectroscopy method to measure erosion rates and absorption coefficients of hydrogenated amorphous carbon films, with potential applications in plasma-wall interaction studies in fusion devices.

Contribution

The paper presents a novel, fast, and simple ex-situ Raman spectroscopy technique for quantifying erosion and absorption in carbon films, validated against ellipsometry.

Findings

Maximum erosion rate at ~450°C observed

Method agrees with ellipsometry measurements

Applicable for studying plasma-wall interactions in fusion

Abstract

We present a fast and simple way to determine the erosion rate and absorption coefficient of hydrogenated amorphous carbon films exposed to a hydrogen atomic source based on ex-situ Raman micro-spectroscopy. Results are compared to ellipsometry measurement. The method is applied to films eroded at different temperatures. A maximum of the erosion rate is found at ~ 450 {\degree}C in agreement with previous results. This technique is suitable for future quantitative studies on the erosion of thin carbonaceous films, especially of interest for plasma wall interactions occurring in thermonuclear fusion devices.