The reaction process of tungsten hexafluoride (WF6) with photochemically deposited hydrogenated amorphous silicon was studied by polarization modulation infrared spectroscopy and quadruple mass spectrometry. Infrared absorption bands due to species (SiH3 and SiH2) incorporated in the hydrogenated amorphous silicon were decreased in intensity during exposure of WF6. The reduction rate was faster for the SiH3 species than for the SiH2 species. The mass spectrometric analysis revealed that evolution of hydrogen into the gas phase took place prior to that of silicon fluorides. These results strongly suggest that WF6 reacts preferentially with the SiH3 species present in the hydrogen-rich surface layer.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)