Fluorine oxygen species, dissociation

This study has established that oxygen difluoride dissociates photo-lytically into a paramagnetic species in which there is a hyperfine interaction between the unpaired electron and one fluorine nucleus. The photolytic rate of formation of the radical species increased with temperature. The decay of the signal intensity in the absence of light after photolysis did not depend on temperature. The kinetics have been interpreted in terms of a photolytic formation scheme. The radical has been characterized by means of the EPR spectrum, but not identified. However, the characteristics of the spectrum show that the radical was Oa-F, rather than F ... 

It is known that the silicon etching rate increases when O2 is added to CF4, because carbon is oxidized by O2, and the fluorine concentration increases. CF4 is unable to react with oxygen, therefore the mechanism for increase in the fluorine concentration may be attributed to the reaction of a radical species generated by dissociation of CF4 with oxygen. The following reaction mechanism was proposed [39,40],... 

The dissociation of chlorofluorocarbons such as CFC13 and CF2C12, as well as other species such as CF4, represents a source of atmospheric fluorine. Fluorine atoms react rapidly with molecular oxygen... 

Formation and reaction of peroiqrl radicals Except for fluorinated organic conqxiunds, the radical species (alkyl, phenyl) generated on dissociative electron ciqiture process have absorption bands at X < 300 nm. The peroxyl radicals gennated on addition of oxygen also have absorption bands at X < 300 nm except for phenyl peroxyl radicals which show absorption band in 400 - 600 nm region [89-92]. Phenyl peroxyl radicals (1%00, E° 0.7 V vs NHE) are much more reactive than alkyl peroxyl radicals... 

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