Application of Two-photon Absorption Laser Induced Fluorescence to validate actinometry measurements of absolute atomic oxygen number density based on improved electron energy distribution functions obtained from PIC simulations

摘要

Actinometry is a non-invasive optical diagnostic that has potential application in industrial plasma processes to monitor absolute number density of atomic oxygen during the process. However, application of the technique is currently limited as the technique relies on theoretical models that have various problems associated with them one of which is a sensitivity to the EEDF in the plasma which affects the rate coefficients used in the model. Particle in cell (PIC) simulations have been used to calculate more accurate EEDFs which were incorporated into the actinometry model to attempt to improve the accuracy of the method. In this work we present results for atomic oxygen number density measured in a capacitive RF plasma tool using both actinometry and Twophoton Absorption Laser Induced Fluorescence (TALIF) which is incorporated as an alternative diagnostic to validate the number densities obtained with the improved actinometry technique.