PLASMA TREATMENT APPARATUS

PURPOSE:To clean and remove a substance adhered to a wall face in a whole region inside a treatment chamber including a gap part sandwiched between an earth shielding body and an inner wall of the treatment chamber by a method wherein a plasma is generated in the gap part. CONSTITUTION:A changeover switch 9 is connected to a side a; a gas which is effective for a cleaning operation is introduced into a treatment chamber 1 from a gas source 1b, and is adjusted to a prescribed pressure. When high-frequency electric power is impressed not only on a cathode electrode 8 but also on an earth shielding body 5 and an anode electrode 3 from a high-frequency power supply 8, a plasma is generated at a gap part between them and an inner wall of the grounded treatment chamber 1. Accordingly, the plasma is generated in a whole region inside the treatment chamber 1 ; in addition, because both the earth shielding body 5 and the anode electrode 3 become substantially at the same potential as the cathode electrode, it is possible to obtain ion energy which is necessary and sufficient for the cleaning operation. By this setup, it is possible to easily clean and remove a substance which has adhered to a wall face in a part sandwiched between the earth shielding body 5 and the treatment chamber 1 by the use of the plasma.