| 摘要 |
<P>PROBLEM TO BE SOLVED: To prolong the lifetime of discharge electrode parts by protecting against processing gas and preventing oxidation. <P>SOLUTION: Electrodes 22 to 25 are covered with electrode covers 22 P to 25 P, and discharge openings 22HL, 22HR to 25HL, 25HR are provided (22HL, 25HR are closed). Further, protection gas intakes 22Q to 25Q which shift in phase by 90° are provided on upstream sides of the discharge openings 22HL, 22HR to 25HL, 25HR. The protection gas flowing in from the protection gas intakes 22Q to 25Q flow in peripheries of discharge electrode parts 22S to 25S to flow out to a discharge space. The protection gas is supplied to the discharge electrode parts 22S to 25S, so the discharge electrode parts 22S to 25S are made unlikely to come into contact with the processing gas. Consequently, oxidation of the discharge electrode parts 22S to 25S is suppressed to prolong the lifetime. <P>COPYRIGHT: (C)2012,JPO&INPIT |
