Substrate processing apparatus and substrate processing method

A substrate processing apparatus for processing a substrate mounted on a mounting table in a processing chamber by supplying a gas to the substrate, the apparatus comprising:

• a partition unit provided, between a processing space where a substrate is provided and a diffusion space where a first gas is diffused, to face the mounting table;
• a first gas supply unit configured to supply the first gas to the diffusion space;
• a plurality of first gas injection holes formed through the partition unit in a thickness direction thereof and configured to inject the first gas diffused in the diffusion space into the processing space;
• and
• a second gas supply unit including a plurality of second gas injection holes opened on a gas injection surface of the partition unit which faces the processing space and configured to independently supply a second gas to each of a plurality of regions arranged in a horizontal direction in the processing space separately from the first gas,
• wherein the plurality of regions includes a central region about a central axis of the substrate and a peripheral region surrounding the central region,
• wherein the second gas supply unit includes a central gas supply unit configured to supply the second gas to the central region and a peripheral gas supply unit configured to supply the second gas to the peripheral region,
• wherein the partition unit is a plate-shaped body,
• wherein the central gas supply unit includes a gas introducing port for a central region formed in a peripheral portion of the plate-shaped body and a central gas channel for the central region where the second gas injection holes are opened, the central gas channel having one end formed in the plate-shaped body to communicate with the gas introducing port for the central region and another end led to the central region of the plate-shaped body along the gas injection surface, and
• wherein the peripheral gas supply unit includes a gas introducing port for a peripheral region formed in a peripheral portion of the plate-shaped body and a peripheral gas channel for the peripheral region where the second gas injection holes are opened, the peripheral gas channel having one end formed in the plate-shaped body to communicate with the gas introducing port for the peripheral region and the other end led to the peripheral region of the plate-shaped body along the gas injection surface.