US Patent 11309167 Active gas generation apparatus and deposition processing apparatus

In the present invention, a gas passing groove, a high-voltage electrode groove and a ground electrode groove formed in an electrode unit base are each spiral in plan view. A high-voltage electrode is embedded in the high-voltage electrode grove, and a ground electrode is embedded in the ground electrode groove. The high-voltage electrode and the ground electrode are arranged on sides of opposite side surfaces of the gas passing groove in the electrode unit base to oppose each other with a portion of the electrode unit base and the gas passing groove therebetween, and are spiral in plan view along with the gas passing groove.