Patent ID: 11491517

Abstract:
The water outlet of a subsystem that includes an ultraviolet oxidation device and the water inlet of each substrate treatment device are connected to each other via a main pipe. A hydrogen peroxide removal device is installed between the ultraviolet oxidation device of the subsystem and a non-regenerative ion-exchange device. In addition, a carbon dioxide supply device is installed at the middle of a pipe that branches from the water outlet of the subsystem to reach the substrate treatment device. According to an aspect, the hydrogen peroxide removal device is filled with a platinum-group metal catalyst. Thus, ultrapure water passed through the ultraviolet oxidation device is used as a base to produce carbonated water in which the concentration of hydrogen peroxide dissolved therein is limited to 2 μg/L or less and to which carbon dioxide is added to adjust resistivity to be within the range of 0.03 to 5.0 MΩ·cm.