Point of Use Plasma system for Exhaust Air Decontamination System for the Semi-Conductor Industry


Green house effect and global warming are the critical issues in this new era. The influence is not only the environment, but also the economic and national safety. The majority gas, PFCs and SF6, the GHG(Green House Gas) defined in Kyoto Protocol are generated gas out from the semiconductor and optical electronics dry etching procedure accumulated and mixed with CVD gas for chamber clean. The special PFCs gases from the tools such as SF6, CF4, C2F6, C3F8, CHF3 and NF3 have to be treated before emission.

A plasma scrubber system was developed and tested as Point of Use abatement system for the treatment of PFC loaded gases coming from a production line from semiconductor industry. The system consists of an arc heated water steam plasma unit followed a combustion chamber and a quench-scrubber-system.

For chemical destrucion of PFC material, a water plasma is favorable because both, the oxygen and the hydrogen, which is necessary to produce the desired products after the high temperature zone-CO, CO2, HF and HCl- are supplied by the heat carrier itself.  Therefore a new plasma torch system using water as plasma gas was developed and tested under the specification to achieve a long lifetime of the electrodes.

The system was developed and tested under industrial condition at a process line in semiconductor industry. It was demonstrated, that, with this process a reduction of PFC in the exhaust gas of > 99.9 % can be achieved.



POU System under development