Vacuum ultraviolet-absorption spectroscopy and delocalized plasma-induced emission used for the species detection in a down-stream soft-etch plasma reactor

Abstract

The VUV-absorption spectroscopy (AS) and the emission spectroscopy (ES) from delocalized probe plasma, are implemented in the downstream chamber of a soft-etch industrial plasma reactor. A CCP plasma, running in the upper compartment in He/NF3/NH3/H2 mixtures at about one Torr, produces reactive species which flow through a shower head into a downstream chamber, where they can etch different µ-electronics materials: Si, SiO2, SiN,... The ES reveals the presence of F and H atoms, while the dissociation rates of NF3 and NH3 are deduced from the AS, as well as the density of HF molecules, produced by chemical chain-reactions between dissociation products of NF3, NH3 and H2.