Substrate processing apparatus

A substrate processing apparatus for processing substrates, comprising:

• a processing container configured to air-tightly accommodate the substrates;
• a plurality of mounting stands configured to mount the substrates within the processing container;
• a process gas supply part configured to supply a process gas from above the mounting stands toward the mounting stands;
• an exhaust mechanism configured to evacuate an interior of the processing container;
• a partition wall disposed within the processing container and configured to independently surround the mounting stands with a gap left between the partition wall and an outer periphery of each of the mounting stands;
• an elevator mechanism configured to move the partition wall up and down between a retracted position and a substrate processing position;
• and
• cylindrical inner walls disposed on a bottom surface of the processing container and configured to independently surround the mounting stands with a gap left between each of the inner walls and the outer periphery of each of the mounting stands,
• wherein substrate processing spaces are formed by the partition wall and the inner walls as the partition wall is moved to the substrate processing position,
• wherein each of the inner walls includes a plurality of process gas exhaust passages,
• wherein each of process gas exhaust passages includes an interior slit inlet through which the process gas existing within the processing space is initially exhausted from the processing space, a channel connected to the interior slit inlet and formed between a body portion of the inner wall and a partition plate formed on an inner surface of the inner wall, the channel configured to guide the process gas by a predetermined length, and an exterior slit outlet through which the process gas is finally exhausted from the processing space, the exterior slit outlet connected to the channel,
• wherein the inner walls are disposed lower than substrate mounting surfaces of the mounting stands, and
• wherein the interior slit inlet and the exterior slit outlet are separated from each other in the circumferential direction of the inner wall with the channel being interposed between the interior slit inlet and the exterior slit outlet, the channel being formed in a circumferential direction of the inner wall, so that a cross section of the channel through which the process gas flows is perpendicular to cross sections of the interior slit inlet and the exterior slit outlet through which the process gas flows.