Substrate liquid treatment apparatus and substrate liquid treatment method

A substrate liquid treatment apparatus that supplies a cleaning liquid to a back surface of a substrate to perform a cleaning treatment, said apparatus comprising:

• a substrate holding unit that horizontally holds the substrate at a central part of the back surface of the substrate;
• a rotary drive mechanism that rotates the substrate holding unit around a vertical axis;
• a back surface purging nozzle that discharges a purge gas onto the back surface of the substrate that is rotating while being held by the substrate holding unit;
• a periphery purging nozzle that discharges the purge gas onto the back surface of the substrate that is rotating while being held by the substrate holding unit;
• a purge gas supplying mechanism that supplies the purge gas to the back surface purging nozzle and the periphery purging nozzle;
• and
• a control unit that controls the rotary drive mechanism and the purge gas supplying mechanism,
• wherein the back surface purging nozzle has a slit-like opening part extending from a central side to a peripheral side of the substrate in a plan view, and wherein vertical distance between the slit-like opening part and the substrate held by the substrate holding unit increases as approaching an end of the slit-like opening part on the central side of the substrate,
• wherein the periphery purging nozzle is installed such that the periphery purging nozzle discharges the purge gas toward a region on the back surface of the substrate, which region is located radially outside an end of the slit-like opening part of the back surface purging nozzle and radially inside an peripheral edge of the substrate, and such that the purge gas is directed toward a central part of the substrate, and
• wherein the control unit controls the rotary drive mechanism and the purge gas supplying mechanism such that, after supplying of the cleaning liquid to the substrate is stopped, the back surface purging nozzle and the periphery purging nozzle discharge the purge gas toward the back surface of the substrate while rotating the substrate having the cleaning liquid adhering thereto.