Patent attributes
The substrate processing apparatus includes first supply piping which guides a processing liquid from a first branching portion to a first chemical liquid nozzle, first return piping which guides the processing liquid from the first branching portion to a tank, a first pressure-loss setting unit which sets a pressure loss so that a pressure loss through the first supply piping is larger than a pressure loss through the first return piping, and a first discharge valve which switches between a first discharge execution state in which the pressure loss through the first return piping is larger than the pressure loss through the first supply piping and a first discharge stop state in which the pressure loss through the first return piping is smaller than the pressure loss through the first supply piping.
