Plasma processing method and plasma processing apparatus

A plasma processing method comprising:

• (a) providing a substrate including a metal-containing film and a mask on the metal-containing film;
• (b) supplying a modifying gas for modifying a surface of the metal-containing film and a carbon-containing precursor;
• (c) forming a modified layer by modifying the surface of the metal-containing film with plasma generated from a gas mixture including the modifying gas and the carbon-containing precursor by supplying first radio frequency power;
• and
• (d) removing the modified layer in a manner that the modified layer and the carbon-containing precursor are caused to react with each other by stopping supply of the first radio frequency power.

A plasma processing method comprising:

• (a) providing a substrate including a first region including metal and a second region including an element other than the metal, on a substrate support including an electrode;
• (b) supplying a gas including at least one of halogen or oxygen and a carbon-containing precursor;
• and
• (c) removing the first region, wherein
• (c) includes
• (c1) a first period in which first radio frequency power is supplied, and
• (c2) a second period alternated with the first period, wherein the first radio frequency power is not supplied or second radio frequency power smaller than the first radio frequency power is supplied in the second period.

A plasma processing apparatus comprising:

• a chamber;
• a substrate support for supporting a substrate in the chamber, the substrate including a first region including a first material and a second region including a second material different from the first material;
• a gas supply configured to supply a modifying gas for modifying a surface of the first region and a carbon-containing precursor in the chamber;
• a plasma generator configured to generate plasma from a gas mixture including the modifying gas and the carbon-containing precursor by supplying first radio frequency power in the chamber;
• and
• a controller, wherein
• the controller is configured to control the gas supply and the plasma generator to
• form a modified layer by modifying the surface of the first region with the plasma, and
• remove the modified layer in a manner that the modified layer and the carbon-containing precursor are caused to react with each other by stopping supply of the first radio frequency power or supplying second radio frequency power smaller than the first radio frequency power.