Patent Application
20130168242
1. Technical Field
The present disclosure relates to magnetic cores, especially to a magnetic core for a cylindrical magnetron sputtering target.
2. Description of Related Art
Vacuum sputtering devices receive sputtering targets. The targets are generally hollow cylindrical targets having magnetic cores mounted on the inner surfaces of the hollow portions of the targets. Commonly, three notches are first defined in the inner surface of the target along the axial direction. The notches are equidistantly distributed. Then a number of magnets are mounted in the notches to form a magnetic core of the cylindrical target. However, it is time consuming and costly to form the notches in the inner surfaces of the targets, as well as the mounting of the magnets to the notches. Additionally, during a deposition process, the cylindrical target must be cooled by cooling water which fills and flows through the cylindrical target. As a result, the magnets mounted in the inner surface of the target will be immersed in the cooling water during the deposition process. The magnets are prone to damage by the cooling water. Thus, the lifespan of the magnets is reduced.
Therefore, there is room for improvement within the art.
Many aspects of the disclosure can be better understood with reference to the following figures. The components in the figures are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
The housing 11 includes a base 113 and a mounting plate 115. The base 113 defines a first notch 1131. The mounting plate 115 defines a second notch 1151. The magnet array 13 is mounted and secured in the second notch 1151 of the mounting plate 115. The base 113 is welded to the mounting plate 115 with the mounting plate 15/magnet array 13 being received in first notch 1131, thus enclosing the magnet array 13 in the housing 11. Alternatively, the base 113 can be incorporated to the mounting plate 115 by adhesives. The base 113 and the mounting plate 115 are both made of stainless steel.
Referring to
Each first magnet 15a and second magnet 17a is separated by a separating block 19a, which allow the first magnets 15a and the second magnet 17a to produce a desired sputtering magnetic field. The second magnet 17a is larger than each first magnet 15a, which gives the magnetic field a more suitable distribution. The mounting surfaces 151, 171, 191, and 181 are not at a same plane, which also provides the magnetic field a better distribution.
The two third magnets 18 respectively located at the two ends of the magnet array 13, allows the magnetic field of the magnet array 13 to form an enclosed magnetic field, with which the sputtering uniformity of the target will be improved and the lifespan of the target prolonged. The separating block 20 is positioned between the outermost magnet segments 13a and the third magnet 18 to provide the enclosed magnetic field a better distribution. The separating block 20 has a mounting surface 201 which may directly contact the mounting plate 115. The separating block 20 may be aluminum blocks, plastic blocks, or ceramic blocks. The separating block 20 is nonmagnetic.
The first magnets 15a, the second magnet 17a, and the third magnets 18 are all made of samarium cobalt alloy.
During assembling of the magnetic core 10, a plurality of second magnets 17a are mounted in the mounting plate 115 and stacked with each other end to end to form a second magnet group 17. A plurality of separating blocks 19a are mounted in the mounting plate 115 and located on the opposite sides of the second magnet group 17 to form two separating block groups 19. A plurality of first magnets 15a are mounted in the mounting plate 115 and located on the sides of the separating block groups 19 to form two first magnet groups 15. Finally, a separating block 20 and a third magnet 18 are mounted orderly in the mounting plate 115 at each end of the magnet array 13. Then, to enclose the magnet array 13 in the housing 11, the base 113 is welded or is adhered to the mounting plate 115. As such, the magnetic core 10 is finished.
Before the magnet array 13 is mounted in the mounting plate 115, the mounting surfaces 151, 171, 191, 181, and 201 may be all coated with adhesive layers to enhance the mounting security of the magnet array 13 to the mounting plate 115.
The magnetic core 10 of the exemplary embodiment can be mounted in a hollow cylindrical target (not shown) along the axis of the target. Because the magnet array 13 is enclosed by the housing 11, the magnets of the magnet array 13 will not be damaged by the cooling water, thus prolongs the lifespan of the magnets.
Additionally, the magnetic core 10 of the exemplary embodiment can be easily assembled, and it is easily to mount the magnetic core 10 in a hollow cylindrical target.
It is believed that the exemplary embodiment and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its advantages, the examples hereinbefore described merely being preferred or exemplary embodiment of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201110454429.4 | Dec 2011 | CN | national |
