Vacuum ultraviolet-absorption spectroscopy and delocalized plasma-induced emission used for the species detection in a down-stream soft-etch plasma reactor
Résumé
Vacuum ultraviolet-absorption spectroscopy (AS) and emission spectroscopy (ES) from delocalized probe plasma are implemented in the downstream chamber of a soft-etch industrial plasma reactor. A capacitively coupled plasma plasma, running in the upper compartment in He/NF$_3$/NH$_3$/H$_2$ mixtures at about 1 Torr, produces reactive species which flow through a shower head into a downstream chamber, where they can etch different μ-electronic materials: Si, SiO$_2$, SiN, etc. The ES reveals the presence of F atoms, while the dissociation rates of NF$_3$ and NH$_3$ are deduced from the AS, as well as the density of HF molecules, produced by chemical chain-reactions between dissociation products of NF$_3$, NH$_3$, and H$_2$. The variations of HF density as a function of the NH$_3$ flow rate suggest the possible formation of NH$_4$F molecules in the plasma
Domaines
Sciences de l'ingénieur [physics]
Origine : Publication financée par une institution
