| 摘要 |
PROBLEM TO BE SOLVED: To enable controlling the concentration of persulfuric acid of a solution to be supplied to a cleaning side by rapidly measuring the concentration of persulfuric acid generated in a cleaning solution supplying system. SOLUTION: The cleaning solution supplying system is provided with an electrolytic reaction device (electrolytic reaction tank 36) for generating persulfuric acid ions from sulfuric acid ions contained in the sulfuric acid solution by electrolytic reaction of a sulfuric acid solution; a circulation line enabling supplying the sulfuric acid solution containing the persulfuric acid ions generated in the electrolytic reaction device to a cleaning side (cleaning tank 1) for cleaning a material to be cleaned (semiconductor wafer 5) as part or all of the cleaning solution, and supplying part or all of the sulfuric acid solution to the electrolytic reaction device when receiving the sulfuric acid solution used as the cleaning solution and returned from the cleaning side; and a persulfuric acid concentration measuring device (electrode portion 41) for measuring the concentration of persulfuric acid in the sulfuric acid solution in the cleaning solution supplying system. COPYRIGHT: (C)2009,JPO&INPIT
|
