SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD

The invention provides a substrate processing apparatus and a substrate processing method, which can reduce the concentration of combustible gas in gas discharged from a mixing device for mixing a phosphoric acid aqueous solution and a precipitation inhibitor and flowing in an exhaust passage. The substrate processing apparatus includes a processing tank, a mixing device, a heating portion, a liquid feeding path, an exhaust fan, an exhaust passage, and a control portion. And the processing tank is used for dipping the substrate in the processing liquid for processing. The mixing device mixes an aqueous phosphoric acid solution with an additive containing an organic solvent to generate a mixed solution as a raw material for the treatment liquid. The heating unit is provided in the mixing device and heats the mixed liquid. The liquid delivery path delivers the mixed liquid from the mixing device to the processing tank. And the exhaust fan exhausts the gas in the mixing device. The exhaust channel is used for gu