Substrate processing apparatus and substrate processing method

A substrate processing apparatus comprising:

• at least one processing part including a processing container and configured to etch a polysilicon film or an amorphous silicon film formed on a substrate using an alkaline chemical liquid;
• a reservoir configured to recover and store the chemical liquid used in the at least one processing part;
• processing lines configured to supply the chemical liquid stored in the reservoir to the at least one processing part;
• a circulation line configured to take out the chemical liquid from the reservoir and to return the taken-out chemical liquid to the reservoir;
• a first gas supply line connected to the circulation line and configured to supply an inert gas to the circulation line;
• a flow rate regulator configured to regulate a flow rate of the inert gas to be supplied to the circulation line by the first gas supply line;
• a controller constituted by a computer and configured to control the flow rate regulator;
• a container connected to the reservoir and configured to temporarily accommodate the chemical liquid and to deliver the chemical liquid to the reservoir;
• a chemical liquid recovery line connected to the container and configured to return the chemical liquid after being used in the at least one processing part to the reservoir via the container;
• and
• a second gas supply line connected to the container and configured to supply the inert gas into an interior of the container,
• wherein the circulation line includes an ejection port configured to eject a mixed fluid of the inert gas supplied by the first gas supply line and the chemical liquid taken out from the reservoir into the chemical liquid stored in the reservoir,
• wherein the container has a wall in which an opening is formed to allow the interior of the container and an interior of the reservoir to communicate with each other,
• wherein the opening is arranged so as to be deviated from an extension line of a flow path of the chemical liquid recovery line, and
• wherein the wall receives and repels the chemical liquid returned to the container by the chemical liquid recovery line.