The Plasma Tech and SICT International Joint Conferences Proceedings

Abstract

This study investigates the optical-emission spectra (OES) of inductively-coupled plasma (ICP) discharges of SF6 / Ar gas mixtures. The impact of the key process parameters of the plasma-chemical etching (PCE) on fluorine radicals concentration has been studied using the optical emission actinometry. It was found that increase of SF6 flow rate within a range between 1,5 sccm and 11,7 sccm leads to an increase in atomic fluorine concentration by 6 times, while reduction of the process pressure during the PCE from 1,65 Pa to 0,65 Pa provides an increase in atomic fluorine concentration more than 1,5 times, and an increase in the RF power absorbed in the plasma from 500 to 700 W is accompanied by an increase in the concentration of fluorine atoms by 1.27 times. The temperature of the substrate holder and the substrate bias voltage have no effect on the concentration of atomic fluorine in the plasma.