METHOD FOR EVALUATING EFFECT OF CLEANING WATER OF CLEANING OBJECT SUBSTRATE, METHOD FOR SETTING WATER QUALITY BASED ON EVALUATION METHOD, AND ULTRAPURE WATER PRODUCTION SYSTEM FOR OBTAINING WATER OF SET WATER QUALITY

摘要

PROBLEM TO BE SOLVED: To provide a method for evaluating an effect of impurities in cleaning water of a cleaning substrate on contamination of the cleaning substrate.SOLUTION: The contamination of the surface of a silicon wafer as the cleaning substrate is caused because an OH group originating in SiOH present on the silicon wafer serves as an adsorption active spot, and metal-containing components, organic substances, and so on adsorb here. Then an amount of SiOH (OH group) after cleaning with an ultrapure water production system 1 as a basic system, and that of SiOH after cleaning, while varying cleaning treatment conditions such as silicon wafer cleaning conditions and water quality conditions, are measured; the optimum water quality is set based on a ratio of both; and the basic system is reconfigured or specifications of components of the basic system are changed so as to ensure the optimum system settings for supplying ultrapure water of the set water quality.