Substrate support, plasma processing system, and plasma etching method

A plasma processing system comprising:

• a plasma processing apparatus;
• and
• a controller,
• wherein the plasma processing apparatus includes:
• a plasma processing chamber;
• a substrate support disposed in the plasma processing chamber;
• a gas supply configured to supply a processing gas to the plasma processing chamber;
• and
• a plasma generator configured to generate a plasma from the processing gas,
• wherein the substrate support includes:
• a substrate support member;
• a base;
• a ceramic plate disposed on the base and having a substrate supporting region and a ring supporting region surrounding the substrate supporting region;
• an insulating annular member disposed around the base and the ceramic plate;
• a fixed edge ring having an inner peripheral portion and an outer peripheral portion, the inner peripheral portion being supported on the ring supporting region, the outer peripheral portion being supported on the insulating annular member, the outer peripheral portion having a first width;
• a movable edge ring disposed on or above the outer peripheral portion of the fixed edge ring and having a second width smaller than the first width;
• a lifter pin extending through the fixed edge ring, extending through the insulating annular member and contacting the movable edge ring to move the movable edge ring;
• and
• an actuator configured to vertically move the lifter pin to move the movable edge ring with respect to the fixed edge ring by the lifter pin,
• wherein the fixed edge ring is disposed on the insulating annular member and the fixed edge ring is disposed on the ceramic plate,
• wherein the insulating annular member and the base are disposed directly on the substrate support member,
• wherein the substrate support member is disposed at a bottom of a chamber of the plasma processing apparatus,
• wherein each of the fixed edge ring, the movable edge ring and the lifter pin is made of an insulating material,
• wherein an entirety of the fixed edge ring is disposed below the movable edge ring in a vertical direction,
• wherein most of the outer peripheral portion of the fixed edge ring is not covered by the movable edge ring,
• wherein the movable edge ring and the lifter pin are disposed radially outside of an RF path through which RF current passes, and
• wherein the fixed edge ring is disposed above the insulating annular member in the vertical direction, and
• wherein the controller is configured to control the plasma processing apparatus to perform:
• supplying the processing gas to the plasma processing chamber;
• generating the plasma from the processing gas;
• etching a substrate;
• and
• vertically moving the movable edge ring by the lifter pin.