TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Gas: The halogen containing gas is perfluorocarbon, chlorofluorocarbon, hydro chlorofluorocarbon or hydrofluorocarbon gas.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Apparatus: The processing apparatus further comprises a concentrating unit, additional gas supply unit, a gas concentration detector, water content removal unit and washing unit.The concentrating unit concentrates the halogen gas to 1 volume% or more between the halogen containing gas supply unit and discharge portion.The additional gas supply unit adds additional gas chosen from concentrated waver vapor, hydrogen, oxygen, ozone, methane, ethane, propane or ammonia based on the halogen group gas concentration.The gas concentration detector outputs the detected concentration as a detection signal and additional gas supply unit equipped with flow-regulation unit to adjust the amount of supply of addition gas based on the detection signal.The concentration unit separates and ejects non-halogen containing gas in reduced concentration and/or concentrates the non-halogen containing gas.A discharge port by which gas is emitted is provided at center of the electrodes.A spacer (334) for forming discharge void length through the dielectric is provided between the ground contact lateral electrode and high voltage lateral electrode.A N piece discharge portion is arranged parallel with respect to the flow of halogen gas containing gas.The gas flow is formed by the side wall which connects between the ground contact lateral electrode at position 1 and N/2+1 position.The discharge portion is supported by one or more elastic component.The water content removal unit removes the water content in halogen containing gas before flowing the discharge portion.The absorbent is provided to the discharge space of the discharge portion.The washing unit removes impurities the halogen containing gas and temperature of washing solution, preferably alkaline is less than atmospheric temperature, preferably more than 5degrees C.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The halogen group gas concentration in the halogen containing gas is detected before flowing in the discharge portion.The halogen containing gas is diluted by a mixture of air, nitrogen, oxygen, carbon dioxide, helium, argon, neon or xenon.The non-halogen containing gas is utilized as purge gas of discharge formation gas ejected from purge gas or purge gas to halogen containing gas supply unit and discharge portion of the discharge formation gas or discharge portion to halogen containing gas supply unit.The halogen containing gas flows to the circumference of the electrode.The electrode discharge treatment finished gas is removed from the discharge port. Preferred Electrode: The electrode is formed of stainless steel, aluminum alloy, titanium alloy, Inconel or hastelloy. The discharge space of the electrode is covered with alumina, titania (TiO2), zirconia (ZrO2), magnesium oxide (MgO), lanthanum oxide (La2O3), calcium oxide (CaO), fluoro group resin or heat resistant plastic.Fluoride processing of the electrode surfaces or spacer surface formed of aluminum alloy or titanium alloy is performed.The dielectric comprises alumina, TiO2, ZrO2, MgO, La2O3, CaO, silica, fluoro group resin or acrylic type resin.The dielectric has outer diameter more than the outer diameter of ground-contact lateral electrode and high voltage lateral electrode.The spacer is formed of stainless steel, aluminum alloy, titanium alloy, Inconel or hastelloy, ceramics, fluoro group resin or heat resistant plastic.