Plasma processing apparatus and plasma processing method

A plasma processing apparatus, comprising:

• a depressurizeable chamber;
• a tray adapted to be carried in and out to the chamber, formed with a plurality of substrate accommodation holes penetrating through thickness thereof, and provided with a substrate support portion for each of the substrate accommodation holes that supports an outer peripheral edge of a lower surface of the substrate accommodated in the substrate accommodation hole;
• an upper portion arranged in the chamber and provided with a tray support portion for supporting a lower surface of the tray that supports the substrates carried into the chamber, a plurality of substrate placement portions on each of which a lower surface of the substrate to be placed, and a concave portion for accommodating the substrate support portion;
• an electrostatic attraction electrode for electrically attracting at least the substrate to the substrate placement portion;
• a dc voltage applying mechanism for applying a dc voltage to the electrostatic attraction electrode;
• and
• a heat conducting gas supply mechanism for supplying a heat conduction gas to a space between the substrate and the substrate placement portion,
• wherein, during carrying of the substrate, the outer peripheral edge of the lower surface of the substrate accommodated in the substrate accommodation hole is supported by the substrate accommodation hole, and
• wherein, during processing of the substrate, the lower surface of the tray is supported by the tray support portion of the upper portion, the lower surface of the substrate is placed on the substrate placement portion so that the substrate is above the substrate support portion, and the substrate support portion is accommodated in the concave portion.