Patent ID: 9038262
Filing Date: 2015-05-26
Classification: B23B,H01L,Y10T

Abstract:
1. A method for holding a disk-shaped article by a device, the device comprises a rotating shaft, and a chuck body driven by the rotating shaft for supporting the disk-shaped article, wherein a first group of clamping elements and a second group of clamping elements are mounted on the edge of the chuck body, each group of clamping elements comprise at least 3 clamping elements each with a ferromagnetic material and able to rotate around a mounting point with respect to the chuck body; the clamping elements in the first group have a first magnet polarity, while the clamping elements in the second group have a second magnet polarity opposite to the first magnet polarity; the inner circumference of the chuck body is provided with two sets of electromagnets having controllable polarity and energization time; the method comprising the step of: in the beginning of cleaning the disk-shaped article, de-energizing the two sets of electromagnets, rotating the chuck body; during cleaning of the disk-shaped article, making the first group of the clamping elements and the second group of the clamping elements clamp alternately by changing the current direction in the electromagnets to clean the clamped portion of the disk-shaped article; wherein when the disk-shaped article is rotated at a low speed, the two sets of electromagnets are energized in the same polarity; when the disk-shaped article is rotated at a high speed, one set of electromagnets is energized to enable the clamping elements in the clamping state to be completely release, while the other set of electromagnets is de-energized; after cleaning the disk-shaped article, releasing all the clamping elements by generating a repulsion force between the electromagnets and the clamping elements.