Abstract: A plasma processing device includes: a chamber; a flat-plate-shaped first electrode; a first high frequency power supply; a helical second electrode disposed outside the chamber and disposed to face the first electrode with a quartz plate forming an upper lid of the chamber therebetween; and a gas introducing unit, in which a second high frequency power supply and a third high frequency power supply are configured to be electrically connected to the second electrode, the second high frequency power supply being configured to apply an AC voltage of a second frequency to the second electrode, the third high frequency power supply being configured to apply an AC voltage of a third frequency to the second electrode, and the third frequency being higher than the second frequency; and two types of AC voltages are configured to be simultaneously applied.

Abstract: A plasma processing device includes: a chamber; a flat-plate-shaped first electrode; a first high frequency power supply; a helical second electrode disposed outside the chamber and disposed to face the first electrode with a quartz plate forming an upper lid of the chamber therebetween; and a gas introducing unit, in which a second high frequency power supply and a third high frequency power supply are configured to be electrically connected to the second electrode, the second high frequency power supply being configured to apply an AC voltage of a second frequency to the second electrode, the third high frequency power supply being configured to apply an AC voltage of a third frequency to the second electrode, and the third frequency being higher than the second frequency; and two types of AC voltages are configured to be simultaneously applied.

Abstract: [Object] To provide a plasma processing method capable of maintaining a uniform in-plane distribution from the start to the end of etching by optimizing etching conditions. [Solving Means] In a plasma processing method according to the present invention, the process of etching a substrate (W) having a mask pattern formed on a surface thereof by using plasma formed in a vacuum vessel (21) and the process of forming a protective film on a side wall portion of an etching pattern formed on the substrate (W) by sputtering a target material (30) disposed in the vacuum vessel (21) by using the plasma are alternately repeated. In the plasma processing method, a uniform in-plane distribution is maintained over a time period from the start to the end of plasma processing by changing a radius of a magnetic neutral line (25) in accordance with progress of the plasma processing including the etching processing and the processing of forming a protective film for the substrate (W).