Raman scattering analysis of silicon dioxide single crystal treated by direct current plasma discharge

Low-k materials such as silicon dioxide (SiO2) play an important role in the semiconductor industry. Plasma has become indispensable for advanced materials processing. In this work a treatment of SiO2 single crystal by direct current plasma discharge is studied in detail. Offline metrology is conducted for silicon dioxide wafers by Raman scattering, energy-dispersive x-ray spectroscopy, and ellipsometry. Broad Raman peak at around 2800 cm-1 is observed for the treated SiO2 wafers. Effects of plasma treatment on position of this peak are reported in the paper. An analysis of this correlation could be a framework for creating virtual etch rate sensors, which might be of importance in managing plasma etching processes.