Plasma processing apparatus

A plasma processing apparatus comprising:

• a processing chamber in which a sample is processed by plasma;
• a radio frequency power supply configured to supply radio frequency power for generating plasma;
• a dielectric plate disposed above the processing chamber to hermetically seal the processing chamber;
• a first gas supply plate disposed below the dielectric plate and configured to supply first gas into the processing chamber;
• and
• a sample stage on which the sample is placed, wherein
• the plasma processing apparatus further comprise a second gas supply plate disposed below the first gas supply plate and configured to supply second gas into the processing chamber,
• in the first gas supply plate, a plurality of first gas holes are formed penetrating a first region,
• in the second gas supply plate, a plurality of second gas holes are formed penetrating a second region,
• in a space between the dielectric plate and the first gas supply plate, the first gas is supplied by a first gas supply unit,
• in a space between the first gas supply plate and the second gas supply plate, the second gas is supplied by a second gas supply unit,
• the first region is a region of a central portion of the first gas supply plate,
• the second region is a region that includes a region facing the first region and is wider than the first region,
• an outer diameter of the dielectric plate is larger than an outer diameter of the first gas supply plate, and
• the outer diameter of the first gas supply plate is larger than an outer diameter of the second gas supply plate,
• each of the dielectric plate and the first gas supply plate includes a lower surface side comprising
• a circular recess portion to enclose a region of gas holes in the lower plate;
• a circumferential first groove formed in an outer circumference region of the lower surface side and constructed to provide a gas flow path;
• an inner annular portion formed between the circular recess portion and the circumferential first groove to contact and be supported by the lower plate;
• an outer annular portion formed adjacent to and radially outside the first circumferential groove to contact a seal included in a support member;
• and
• a plurality of second grooves extending in a radial direction and formed in the inner annular portion and through which the circular recess portion and the circumferential first groove communicate with each other.