ULTRASONIC CLEANING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic cleaning method which enables the efficient cleaning of an object to be cleaned. SOLUTION: In cleaning the object to be cleaned by irradiating a cleaning liquid wherein a dissolved gas is present with ultrasonic waves, such steps are repeated over a predetermined period as to continuously perform irradiation with ultrasonic waves for at least 0.2 msec or more and as to stop the irradiation of the ultrasonic waves for at least 0.1 msec or more. This can prevent the generation of large bubbles for blocking the transmission of the ultrasonic waves, efficiently generating radicals contributed to cleaning, and efficiently cleaning the object to be cleaned. COPYRIGHT: (C)2008,JPO&INPIT