To remove contamination materials as particles without giving physical, electrostatic destruction damage to a substrate surface by blowing electrolytic ion water from a nozzle through at least one of a low-pressure water piping or a high-pressure water piping.

Relating to a washing equipment, pure water is blown out from a high-pressure piping 3 connected to a high-pressure pump 1, and electrolytic ion water is blown out from a low-pressure water piping 2, toward a wafer 5 placed on a rotative supporting stage. The high-pressure pump 1 comprises, within it, an iron water generating part 1a which generates electrolytic ion water. Further, relating to a nozzle 4 provided at a tip end of pipings 2 and 3, a tip end part of the high-pressure water piping 3 is allocated at its center part, while a tip end part of the low-pressure water piping 2 so allocated as to surround the high-pressure water piping 3. 10-200 kgf/cm2, for example, is appropriate for a water pressure of high-pressure water, while 0.1-2.0 L/min for flow rate of low-pressure water.