Patent ID: 6021785
Filing Date: 2000-02-08
Classification: B08B,H01L,Y10S

Abstract:
Method for cleaning a surface of a disk-shaped object, by sonification and with water as rinsing medium, comprising the steps of:holding a disk firmly on a supporting device and rotating said disk;approaching the disk surface that is to be cleaned with an ultrasonic transmitter, a radiating surface of the transmitter having a separation gap from the disk surface in a millimeter range;producing a flowing film of ultra-clean water between the disk surface and the transmitter radiating surface to carry away and remove particles dislodged from the disk surface, said flowing film being applied beside and in front of said transmitter in a direction of disk rotation and filling the gap between the transmitter surface and the disk surface to be an efficient medium for propagating ultrasonic waves;generating said ultrasonic waves by said transmitter with frequencies for cleaning purposes to break atomic and/or molecular bonds;compensating a size difference between the radiating surface of the ultrasonic transmitter and the disk surface that is to be cleaned, by providing relative motion between the ultrasonic transmitter and the disk, one of the disk and the transmitter being moved in a plane parallel to the disk surface to scan the entire disk surface that is to be cleaned by the transmitter at least once.