Patent ID: 11935763
Assignee: SCREEN HOLDINGS CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 0:
1. A substrate processing apparatus comprising:
a substrate holder which rotates a substrate while holding the substrate;
a chemical-liquid nozzle which discharges a chemical liquid toward the substrate held by the substrate holder;
a cylindrical cup which receives a processing liquid scattered from the substrate held by the substrate holder;
a circulation pipe which defines a circulation path through which a chemical liquid within a chemical-liquid tank in which a chemical liquid to be supplied to the chemical-liquid nozzle is stored is circulated, wherein a downstream end of the circulation pipe is directly connected to the chemical-liquid tank;
a supply pipe which guides, to the chemical-liquid nozzle, the chemical liquid supplied from the chemical-liquid tank to the circulation pipe;
a supply valve which is switched between an open state where the chemical liquid flowing within the supply pipe toward the chemical-liquid nozzle is passed and a closed state where the supply of the chemical liquid from the supply pipe to the chemical-liquid nozzle is stopped;
a recovery pipe which guides the chemical liquid from the cup to the chemical-liquid tank, wherein flow of the chemical liquid in the recovery pipe is independent of the circulation pipe;
a recovery valve which is switched between an open state where the chemical liquid flowing within the recovery pipe toward the chemical-liquid tank is passed and a closed state where the supply of the chemical liquid from the recovery pipe to the chemical-liquid tank is stopped;
a branch pipe which is connected to the circulation pipe and the recovery pipe and guides the chemical liquid within the circulation pipe to the recovery pipe;
wherein the circulation pipe is configured so that the chemical liquid flowing into the circulation pipe from the chemical-liquid tank is capable of being returned to the chemical-liquid tank via the downstream end of the circulation pipe, without having flowed through any of the supply pipe, the branch pipe and the recovery pipe;
a branch valve which is switched between an open state where the chemical liquid flowing within the branch pipe toward the recovery pipe is passed and a closed state where the supply of the chemical liquid from the branch pipe to the recovery pipe is stopped;
a drain pipe which guides a liquid flowing downstream within the recovery pipe toward the recovery valve to outside the recovery pipe; and
a drain valve which opens and closes an interior of the drain pipe.