Patent ID: 8399794

Claim:
A method for generating an atmospheric pressure plasma, comprising: generating a plasma by supplying a first inert gas into a reaction vessel forming a reaction space and applying a high-frequency voltage to an antenna disposed in the vicinity of the reaction space to eject a primary plasma comprising the first inert gas that has been made into an inductively coupled plasma from the reaction space; and expanding plasma to form a mixed gas area which contains a second inert gas as a main ingredient and a proper amount of a reactive gas mixed with the second inert gas so that the primary plasma collides with the mixed gas area at a portion lower than a lower end of the reaction vessel in order to generate a secondary plasma comprising the mixed gas that has been made into the plasma and the secondary plasma expands in the mixed gas area, wherein a mixed gas vessel is disposed adjacently to a side of the lower end of the reaction vessel, and a gas inlet disposed in an upper position of the mixed gas vessel supplies the mixed gas to the inside of the mixed gas vessel disposed on the periphery of the reaction vessel.