Substrate processing apparatus and substrate processing method

A substrate processing apparatus that removes, from a substrate, a residual liquid remaining on the substrate after pattern formation, comprising:

• a substrate holder that holds and rotates the substrate about an axis extending in a vertical direction;
• a nozzle device having a liquid discharger, a first gas injector and a second gas injector;
• a fluid supply system that supplies a processing liquid having a surface tension lower than that of the residual liquid, a first gas and a second gas to the nozzle device;
• a relative movement device that moves the nozzle device having one attitude relative to the substrate between an upper position that is higher than the substrate held by the substrate holder by a predetermined distance and a lower position that is lower than the upper position and higher than the substrate, and moves the nozzle device having the one attitude in a horizontal direction relative to the substrate;
• and
• a controller, wherein
• the liquid discharger, with the nozzle device having the one attitude, is formed to downwardly discharge the processing liquid supplied from the fluid supply system,
• the first gas injector, with the nozzle device having the one attitude, is formed to downwardly inject the first gas supplied from the fluid supply system,
• the second gas injector, with the nozzle device having the one attitude and being arranged in a space above the substrate held by the substrate holder, is formed to radially inject the second gas supplied from the fluid supply system toward an outer peripheral end of the substrate in plan view, and
• the controller
• controls the substrate holder such that the substrate held by the substrate holder is rotated,
• executes liquid replacement control for controlling the fluid supply system and the relative movement device such that, with the residual liquid present on the substrate held by the substrate holder, the processing liquid is discharged onto the substrate from the liquid discharger of the nozzle device,
• after the liquid replacement control, executes first gas replacement control for controlling the relative movement device such that, with the processing liquid present on the substrate, the nozzle device is located at the upper position and the first gas injector is opposite to a center of the substrate,
• after the first gas replacement control, executes second gas replacement control for controlling the fluid supply system and the relative movement device such that the nozzle device is lowered from the upper position to the lower position while the first gas and the second gas are respectively injected from the first gas injector and the second gas injector, and
• after the second gas replacement control, executes third gas replacement control for controlling the fluid supply system and the relative movement device such that the nozzle device located at the lower position is moved from a center toward the outer peripheral end of the substrate while the first gas and the second gas are respectively injected from the first gas injector and the second gas injector.