Preliminary Study on Plasma-Catalyst Combination for CF4 Removal

One of the environmental issues in semiconductor and flat panel manufacturing industries is to reduce emission of perfluorocarbons(PFCs) used in etching process and cleaning CVD chambers [1]. At present, several types of PFCs abatement device are already installed in the industries, which are incinerator, catalytic combustor, and plasma treatment systems. Removal of CF4 has been tried via catalytic reaction of CF4 decomposition. This study exploits a possible way of plasma-catalyst combination for the removal of CF4. Rotating arc reactor that can produceone of thermal plasma [2] and following catalyst bed has been applied. In this configuration, arc plasma itself destroys CF4 and also provides heat required for the catalytic reaction. From experiments, the removal rate of CF4 was estimated by plasma only and plasma-catalyst combination system. The quantity of water vapor which can prevent reverse reaction of decomposed CF4 was also considered to present optimal quantity of water in CF4 removal reaction.From this work, the feasibility of the combination of plasma and catalyst is confirmed and further studies are needed to realize this hybrid system in an optimal way for real applications.