US Patent 7767026 Substrate processing apparatus and substrate processing method

An on-off valve 81 is opened during rinsing, whereby a part of DIW supplied to a processing liquid supply section 43 is guided into inside a suction pipe 82. After rinsing, a puddle is formed between a lower cleaning nozzle 29 and the bottom surface of a wafer. As the on-off valve 81 is opened while an on-off valve 86 is kept close, the puddle is sucked at a first speed (V1) which is regulated by a needle valve 85 and set to a relatively slow speed. Once the puddle is collected into inside the lower cleaning nozzle 29, the on-off valve 86 is opened so that the puddle is sucked at a second speed (V2) which is regulated by a needle valve 84 and which is faster than said first speed.