JPH047888Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a polishing head used to hold a workpiece in a flat surface polishing apparatus for polishing one side of a workpiece such as a semiconductor wafer.

[Prior Art] For example, a polishing head as shown in FIG. 2 has been conventionally used in a flat surface polishing apparatus such as a polishing machine or a wrapping machine that polishes one side of a workpiece. This is pushrod 1
A reference plate 4 is rotatably and swingably attached to a head shaft 2 connected to a head shaft 2 via an alignment bearing 3, and a mounting surface 6 for a work holding block 5 is formed on the lower surface of the reference plate 4. A water cooling chamber 7 is defined behind the mounting surface, and the water cooling chamber 7 is divided into sections.
While cooling water is supplied cyclically through channels 8 and 9 inside the head shaft 2, the workpiece 10 attached to the holding block 5 is pressed against the surface plate 11 and polished.

However, in the conventional polishing head described above, a specially constructed seal member 12 is interposed between the tip of the head shaft 2 and the reference plate 4, and this seal member allows the water cooling chamber 7 and the alignment bearing 3 to be connected to each other. In addition to providing a liquid-tight partition between the
There is a drawback that a very large unbalanced load is applied to the sealing member 12 due to the displacement of the reference plate 4, causing wear and tear on the sealing member 12 and making sealing impossible.

[Problems to be solved by the invention] The problems of the invention are to prevent wear of the seal member and to simplify the structure by configuring the seal member so that the unbalanced load caused by the swinging of the reference plate does not directly act on the seal member. An object of the present invention is to provide a polishing head that allows the use of a sealing member.

[Means for solving the problems] In order to solve the above problems, in the present invention,
A reference plate equipped with a mounting surface for attaching a workpiece holding block and a water cooling chamber for cooling is rotatably and swingably attached to the head shaft via an alignment bearing, and is formed inside the reference plate. In this space, a seal case located between the water cooling chamber and the alignment bearing is rotatably attached to the head shaft via a bearing and a seal member, and the seal case and the reference plate are connected relative to each other. It is characterized in that they are connected so that they can swing but their relative rotation is restricted, and that a diaphragm is stretched between them.

[Operation] A workpiece holding block is attached to the mounting surface of the reference plate, and while cooling water is supplied to the water cooling chamber, the workpiece attached to the holding block is pressed against the surface plate and polished.

At this time, the cooling water in the water cooling chamber is sealed by the seal member between the seal case and the head shaft and by the diaphragm between the seal case and the reference plate, and does not leak to the alignment bearing side.

Further, even if the reference plate swings about the alignment bearing, the displacement is absorbed by the diaphragm and is not transmitted to the seal case. Therefore, the unbalanced load caused by the displacement of the reference plate is not transmitted to the seal member via the seal case, thereby preventing wear and damage of the seal member.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail based on the drawings. In FIG. 1, 20 is a head shaft connected to a push rod (not shown) of a polishing device, and 21 is the head shaft 20. 2 shows a reference plate rotatably and swingably attached via an alignment bearing 22.

The head shaft 20 has a cooling water inlet 23 and an outlet 24 on its side, and has a supply passage 25 and a discharge passage 26 inside thereof communicating with these inlets and outlets, and the supply passage 25 is connected to the head. axis 20
The discharge passages 26 are opened at the lower end side of the lower end.

On the other hand, the reference plate 21 includes a cylindrical base member 27 having a mounting portion 27a for the alignment bearing 22, and a cap-shaped base member 27 liquid-tightly fixed to the base member 27 with screws 31 via an O-ring 30. tip member 28
and a disc-shaped bottom member 29 liquid-tightly fixed to the lower surface of the tip member 28 with a screw 33 via an O-ring 32.
A mounting surface 36 is formed for mounting a work holding block 34 to which a large number of works 35 are attached, and an annular mounting surface is provided between the bottom member 29 and the tip member 28 for flowing cooling water during polishing of the works 35. A water cooling chamber 37 is formed. This water cooling chamber 37 communicates with the supply channel 25 in the head shaft 20 through a through hole 40, and also communicates with the discharge channel 26 through another through hole 42 opened with a baffle plate 41 in between. The cooling water flowing in from the channel 25 flows into the water cooling chamber 37 so as to bypass the baffle plate 41.
After flowing inside, it flows out to the outside from the discharge flow path 26.

In addition, in the space 44 formed inside the reference plate 21, a seal case 45 located between the water cooling chamber 37 and the alignment bearing 22 is provided.
is rotatably attached to the head shaft 20 via a bearing 46 and a seal member 47 with a slight distance between the seal case 45 and the base member of the reference plate 21. 27, a pin 49 connects the grooves 45a and 27b in a state that allows relative rocking but restricts relative rotation.
The water cooling chamber 37 and the alignment bearing 2
A diaphragm 48 is provided to cut off the gap between the two.

In the figure, 50 is a nipple for supplying lubricant to the alignment bearing 22, and 51 is a cover that covers the connecting portion between the head shaft 20 and the reference plate 21.

When using the flat surface polishing head having the above configuration, the head shaft 20 is connected to a push rod in a polishing device, and the holding block 34 to which a number of works 35 are attached is attached to the mounting surface 36 by appropriate means. Then, while supplying cooling water to the water cooling chamber 37 through the inlet 23, the workpiece 35 is pressed against the surface plate and polished.

Here, the cooling water supplied to the water cooling chamber 37 is supplied to the seal member 47 interposed between the seal case 45 and the head shaft 20 and the diaphragm stretched between the seal case 45 and the plate 21. 48 to prevent leakage to the alignment bearing 22 side.

In addition, the reference plate 21 is aligned with the alignment bearing 2.
2, the displacement is absorbed by the diaphragm 48 and is not transmitted to the seal case 45. Therefore, the uneven load caused by the swinging of the reference plate 21 is applied to the seal case 4.
5 does not act on the sealing member 47, thereby preventing its wear and damage.

[Effects of the invention] As described above, according to the invention, the displacement caused by the rocking of the reference plate is absorbed by the diaphragm stretched between the reference plate and the seal case. It is possible to prevent unbalanced loads due to displacement, that is, rocking, from acting on the seal member between the seal case and the head shaft, and to reliably prevent wear and damage of the seal member,
This makes it possible to use a general-purpose sealing member that has a simple structure and is inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a conventional example. 20...Head shaft, 21...Reference plate, 22...Alignment bearing, 34...Holding block, 35...Workpiece, 36...Mounting surface, 37...
Water cooling chamber, 44...Space, 45...Seal case, 46...Bearing, 47...Seal member,
48...Diaphragm.

Claims (1)

[Scope of utility model registration request] A reference plate equipped with a mounting surface for attaching a workpiece holding block and a water chamber for cooling is rotatably and swingably attached to the head shaft via an alignment bearing, and a reference plate is provided inside the reference plate. In the space formed, a seal case located between the water control chamber and the alignment bearing is rotatably attached to the head shaft via the bearing and the seal member, and the seal case and the reference plate are moved relative to each other. 1. A surface polishing head characterized in that the heads are connected in such a manner that they can be oscillated but their relative rotation is restricted, and a diaphragm is stretched between them.