Application of surface wave plasma technology for effective abatement ofenvironmentally harmful gases such as perfluorocompounds and chlorofluorocarbons isinvestigated. Perfluorocompounds (PFCs) are gases that contribute to forced globalwarming and have been favored for wafer etch and chamber clean applications in thesemiconductor industry. Chlorofluorocarbons (CFCs) are ozone depleting gases thatwere used as refrigerants for commercial and domestic condensers and air conditioners,but current reserves still pose threats to environmental sustainability. Increased averageglobal temperatures and further destruction of the ozone layer have prompted proposalof international initiatives such as the Montreal Protocols and the Kyoto Agreement tocurtail emissions of such fugitive gases into the environment. These have increased theneed for effective abatement technologies to control such emissions and include surfacewave plasma abatement, the subject of this dissertation. Surface wave plasmas areconsidered high frequency non-equilibrium traveling wave discharges in contrast to themore frequently used standing wave discharges. The use of surface wave plasmas havethe advantages of a variety of discharge vessel shapes, reproducibility of application, numerous operating conditions and large plasma volumes which ultimately produce low,molecular weight byproducts that are associated with high effective electrontemperatures but low heavy particle temperatures. For these reasons, surface waveplasma abatement technology was developed for the destruction and removal of PFCsand CFCs.Results include final destruction and removal efficiencies (DREs) foroctafluorocyclobutane greater than 99.8%, dichlorodifluoromethane greater than99.995% and trichlorofluoromethane greater than 99.999% using moderate appliedmicrowave powers of less than 2000 watts with the production of low molecular weightbyproducts, such as CO2, CO, HF and HCl, that prevent environmentally harmfulprocess emissions from entering the atmosphere. Characterizations of the initial andfinal products were accomplished by the use of Fourier transform infrared spectroscopyand quadrupole mass spectrometry to provide independent quantitative analyses ofplasma processes. In addition to these analytical methods, Global_Kin a kinetic model,of plasma reactions were conducted and compared to all the experimental datadetermined in order to facilitate understanding of the chemistry involved in the surfacewave plasma abatement applications studied. Basic plasma reaction mechanisms weredetermined for the abatement of octafluorocyclobutane and dichlorodifluoromethane.
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