Model-based analysis of the silica glass film etch mechanism in CF_4/O_2 inductively coupled plasma

摘要

The analysis of the Er-doped silica glass films (62%SiO_2-30%B_2O_3-8%P_2O_5 + 0.2 wt%. Er_2O_3) etch mechanism in the CF_4/O_2 inductively coupled plasma was carried out using the combination of simplified models for plasma chemistry and etch kinetics. As the O_2 mixing ratio in the CF_4/O_2 plasma increases from 0% to 30%, the etch rate decreases monotonically in the range of 385-190 nm/ min that contradicts with the behavior of F atom density and flux. From the model-based analysis, it was found that, at low ion bombardment energies, the etch process followed the formal kinetics of ion-assisted chemical reaction and was controlled by both neutral and ion fluxes.