JP2003053660A - Block forced driving type one-side polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a block forced driving type one-side polishing device preventing a center roller from being damaged by unnecessitating a driving mechanism exclusive for driving the center roller and preventing direct contact of the center roller and each block, and having a simple structure and excellent durability. SOLUTION: The center roller 8 is fixed to a center part of a surface plate 2 so that the center roller 8 is rotated together with the surface plate 2. A plurality of idle rollers 9 are disposed around the center roller 8 so that the idle rollers 9 is driven and rotated at fixed positions by bringing the idle rollers 9 into contact with the center roller 8. A plurality of blocks 3 holding workpieces are supported in states in which the blocks 3 are brought into contact with a guide roller 21 disposed around the surface plate 2 and the idle rollers 9. The blocks 3 are pressurized by a pressure plate to press the blocks 3 on the surface plate 2 for rotating the workpieces. Therefore, the workpieces are polished, while driving and rotating each block 3 by the center roller 8 via the idle rollers 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-side polishing apparatus for holding a work such as a semiconductor wafer on a block and pressing the work against a surface plate rotated by the block to polish the work. Block forced drive that allows the blocks waiting on the surface plate to be forcibly rotated when loading the blocks sequentially onto the surface plate or when unloading the blocks from the surface plate after finishing polishing. Type single-side polishing apparatus.

[0002]

2. Description of the Related Art In the case of polishing one side of a work such as a semiconductor wafer by a one side polishing apparatus, Japanese Patent Publication No. 63-20674.
As disclosed in Japanese Patent Publication, a plurality of circular blocks are made to hold a work, respectively, these blocks are sequentially supplied on a surface plate and arranged at equal intervals, and then each block is pressed by a top ring. As a result, it is known that a work is pressed against a rotating surface plate through the block to polish the work. In this polishing apparatus, a center roller is arranged at the center of the surface plate so as to be driven and rotated by a drive system different from the surface plate, and each block is brought into contact with the center roller when polishing a work. By doing so, it is forced to rotate. Also, when loading or unloading the block, the block waiting on the surface plate is brought into contact with the center roller to rotate.

However, in the above-mentioned conventional polishing apparatus, the center roller is driven and rotated by a drive system different from the surface plate, so that a separate drive mechanism is required for the surface plate and the center roller. As the structure was complicated. Further, since the block is directly brought into contact with the center roller and driven during polishing, loading or unloading of the work,
For example, when a heavy block is loaded, there is a problem that the center roller is damaged by the impact when the block comes into contact with the center roller, and it becomes easy to support the subsequent driving of the block. In such a case, The entire center roller must be replaced.

[0004]

DISCLOSURE OF THE INVENTION The technical problem of the present invention is that the center roller does not require a dedicated drive mechanism for driving and the center roller is prevented from directly contacting with each block. It is an object of the present invention to provide a block forced drive type single-side polishing machine which is not damaged and has a simple structure and excellent durability.

[0005]

In order to solve the above problems, according to the present invention, a surface plate driven and rotated by a drive source is supplied at equal intervals around a rotation center of the surface plate when polishing a work. , A plurality of circular blocks arranged to press the held work against the surface plate, one center roller installed to rotate together with the surface plate in the center of the upper surface of the surface plate, and the center A plurality of idle rollers which are arranged around the roller so as to be rotatable at equal intervals so as to be in contact with both the center roller and the block, and which are driven to rotate around their own axis at a fixed position by the rotation of the center roller. , Is rotatably disposed around the surface plate and at a position corresponding to each idle roller, and abuts a block on the surface plate to bring the block into contact with the idle roller. A block having a plurality of guide rollers which are movable between a supporting position for supporting in contact with each other and a standby position which is separated from the block and allows the block to move by rotation of a surface plate. A forced drive single-side polishing machine is provided.

In the single-side polishing machine having the above structure,
When polishing a work, the work is held in a block, and the blocks are sequentially supplied by a robot one by one on a surface plate, and the surface plate is rotated to move each block to move these blocks. Is placed at a predetermined position on the surface plate. That is, when the block is supplied on the surface plate, the surface plate slowly rotates and the supplied block is
The first guide roller and the idle roller moving to the supporting position are brought into contact with each other and temporarily supported at that position. Immediately before the next block is supplied, the guide roller once moves to the standby position, releases the supported block, and sends it out to the guide roller of the next stage,
It returns to the supporting position again and supports the next block fed. By repeating the same operation, each block is sequentially fed one position at a time, and the positioning on the surface plate is performed.

When the positioning of the blocks is completed, each block is pressed by a pressure plate, and while the polishing plate is being supplied while the polishing liquid is being supplied to the plate, the plates are rotated to press the workpieces against the plate. And then polished.

When the polishing is completed, as in the case of the above-mentioned loading, the platen is slowly rotated and each guide roller is moved between the standby position and the support position, so that each block is conveyed one position at a time. Sequentially move to the unloading position and take out from the surface plate at that position.

Here, since the block waiting on the surface plate is driven and rotated at that position by the rotation of the surface plate via the center roller and the idle roller during loading and unloading of the block, At the time of unloading after polishing, the polishing liquid on the surface plate appropriately flows, and it is possible to prevent generation of minute scratches due to rubbing between the surface plate and the work. During the loading and unloading, it is desirable to perform the work while supplying the rinse liquid onto the surface plate.

Thus, according to the present invention, since the center roller is fixed to the surface plate and rotated together with the surface plate, a drive mechanism dedicated to the drive of the center roller is not required, and the structure is reduced. However, the manufacturing cost can be kept low. Moreover, since the center roller is prevented from coming into direct contact with each block and is brought into contact with each other through the idle roller, the center roller is not damaged by the contact with the block, and the idle roller should not be damaged. Even if it is damaged, it is only necessary to replace it, and it is not necessary to replace the large and expensive center roller, which is also advantageous in that the structure is simple and the durability is excellent.

In the present invention, the center roller has a conical portion located at the center and an annular flat portion surrounding the conical portion, and the idler rollers contact the outer peripheral surface of the flat portion. is doing.

According to a specific embodiment of the present invention, a first cover member, which covers the upper portion of the center roller and rotates together with the center roller, is provided at the center of the surface plate, and the first cover member. And a non-rotating second cover member which covers the upper part of the above, and each of the idle rollers is rotatably attached to the second cover member, and a central portion of the first cover member and the second cover member. In the center roller, a liquid supply pipe for supplying a polishing liquid is installed so as to face the center of the upper surface of the center roller, and a flow path for guiding the polishing liquid supplied from the liquid supply pipe onto the surface plate is provided in the center roller. And the first
It is provided radially between the cover member and the cover member.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the drawings. In FIGS. 1 and 2, 1 is a machine of a single-side polishing machine, 2 is a rotatably installed on the machine 1 and is driven and rotated by a driving means (not shown), and a polishing surface plate 3 holds a work W. A plurality of circular blocks 4 indicate a plurality of pressure plates which are arranged above the surface plate 2 and can be raised and lowered by air cylinders 5, respectively. After being arranged at equal intervals, the blocks 3 are each pressed by a pressure plate 4, so that the work W is pressed against the rotating surface plate 2 through the blocks 3 and polished. .

As can be seen from FIGS. 2 and 3, one center roller 8 and a plurality of idle rollers 9a to 9d are disposed in the center of the upper surface of the surface plate 2. Of these, the center roller 8 has a conical portion 8a located at the center and an annular flat portion 8b surrounding the conical portion 8a. Screws are provided at a plurality of positions near the outer end of the conical portion 8a. It is fixed to the surface plate 2 by 10 and rotates integrally with the surface plate 2. The upper surface of the center roller 8 has a first cover for covering the conical portion 8a.
Since the cover member 11 is rotatably supported by the non-rotating second cover member 12 that covers the outside thereof,
The center roller 8 is in contact with the conical portion 8a.
It is installed so as to rotate together with. Then, the central hole 11 in the central portion of the first cover member 11
In the inside of a, the center shaft 1 hanging from the machine body 1
4, a liquid supply pipe 15 for supplying a polishing liquid is introduced in a state where the liquid supply port at the lower end is desired at the top of the conical portion 8a, and the conical surface on the lower surface of the first cover member 11 is provided. The conical surface 11b that abuts the portion 8a is radially provided with a flow path 16 for guiding the polishing liquid supplied from the liquid supply pipe 15 onto the surface plate 2.

The second cover member 12 is fixedly attached to the lower end of the center shaft 14, and covers the upper surface and the peripheral side surface of the first cover member 11 and the flat portion 8b of the center roller 8. The bearing 17 interposed between the first cover member 11 and the first cover member 11 allows relative rotation with respect to the first cover member 11. Then, the idle rollers 9a to 9d are rotatably supported by the vertical support shaft 19 on the bearing portion 18 provided at a plurality of locations on the outer circumference of the second cover member 12 at equal intervals, and the flat portion 8b of the center roller 8 is rotated. The center roller 8 is mounted in contact with the outer peripheral surface, and is driven to rotate around its own axis at a fixed position in a direction opposite to that of the center roller 8 by frictional force due to the rotation of the center roller 8. The idle rollers 9a to 9d are represented by a common reference numeral "9" except when it is necessary to distinguish them.

Around the surface plate 2, a plurality of guide rollers 21 for positioning the block 3 on the surface plate 2 at positions corresponding to the respective idle rollers 9.
a to 21d are provided. That is, as can be seen from FIG. 4, the plurality of columns 23 established around the surface plate 2 are
An arm 24 rotatable by a constant angle is provided by an air cylinder (not shown), the guide rollers 21a to 21d are mounted on each arm 24 at a constant angle, and each arm 24 is operated by the operation of the air cylinder. It moves simultaneously between the first position shown by the solid line and the second position shown by the chain line. When the arm 24 rotates to the first position, the guide roller 21a
When ˜21d occupies the supporting position projecting on the surface plate 2, the block 3 is supported in a state of being in contact with the idle roller 9, and when the arm 24 is rotated to the second position,
The guide rollers 21a to 21d are moved from the surface plate 2 to the retracted standby position to release the block 3 and allow the surface plate 2 to move by rotation.

Further, as shown in FIG. 2, sensors 22a to 22d for detecting blocks on the surface plate are attached to the machine body 1 and arranged at intermediate positions between adjacent guide rollers. These sensors 22a-22d
Is for projecting an ultrasonic wave from a position above the surface plate 2 toward the surface plate 2 and detecting the presence or absence of the block 3 from the reflected wave thereof. The detection signals of the blocks from these sensors 22a to 22d are used to detect the above. Each guide roller 21a-21
d is changed from the standby position to the support position.

In the single-side polishing machine having the above structure,
In polishing the work W, a plurality of blocks 3a to 3d holding the work W are sequentially supplied one by one onto the surface plate 2 and positioned by a robot which also serves as loading means and unloading means. FIG. 5 shows an example of the positioning method.

That is, as shown in FIG. 1A, first, the first block 3a holding the work W is supplied from the loading / unloading position P onto the surface plate 2 by the robot. At this time, each of the guide rollers 21a to 21d has been moved to the supporting position in advance. Therefore, when the first block 3a is supplied and the surface plate 2 rotates in the direction of the arrow, as shown in FIG. The block 3a includes a first guide roller 21a and a first guide roller 21a.
It comes into contact with the idle roller 9a and temporarily stops at that position. Then, the center roller 8 is rotated by the rotation of the surface plate 2.
Also, since the idle roller 9a rotates, the first block 3a is forcibly rotated by the idle roller 9a.

Next, as shown in FIG. 5C, the second block 3b is fed by the robot from the loading / unloading position P onto the surface plate 2. Just before the feeding, each guide is guided by a control signal from the robot. The rollers 21a to 21d move to the standby position. Therefore, the first guide roller 21a and the first idle roller 9a supported by the first guide roller 21a
The block 3a is released and moves with the rotation of the surface plate 2. Then, the first sensor 22a is connected to the first block 3
When a is detected, each guide roller 2 at the standby position
1a to 21d move to the supporting position all at once, and
As shown in FIG. 3D, the block 3a contacts the second guide roller 21b and the second idle roller 9b at the next position, and is supported at that position while being forcibly rotated by the second idle roller 9b. It In this state, the second block 3b is supplied onto the surface plate 2 and is moved by the rotation of the surface plate 2, and abuts on the first guide roller 21a and the first idle roller 9a as shown in FIG. Supported in that position.

Subsequently, as shown in FIG. 5F, the third block 3c is supplied onto the surface plate 2, and at this time, the guide rollers 21a to 21a are also driven by a signal from the robot.
d moves to the standby position, releases the first block 3a and the second block 3b, and moves them to the next position. When the second sensor 22b and the first sensor 22a detect the first block 3a and the second block 3b, respectively, the guide rollers 21a to 21d move to the supporting position, and as shown in FIG. The block 3a has a third guide roller 21c and a third idle roller 9c.
And the second block 3b abuts on the second guide roller 21b and the second idle roller 9b and is rotatably supported at their respective positions. The third block 3c is supplied onto the surface plate 2 in this state,
Of the first guide roller 21a and the first idle roller 9a to be supported at that position.

Similarly, the fourth block 3d is shown in FIGS.
As shown in E, the first to third blocks 3a to 3c are moved to one position and then supplied onto the surface plate 2 to
By contacting the guide roller 21a and the first idle roller 9a, the positioning of the blocks 3a to 3d is completed. It should be noted that at the time of loading and unloading the work W, it is desirable to perform the work while supplying the rinse liquid onto the surface plate through the central liquid supply pipe 15.

Thus, when the loading of the four blocks 3a to 3d is completed and they are positioned at the predetermined positions on the surface plate 2, the pressure plates 4 descend to press the blocks 3a to 3d. Thus, the work W is pressed against the surface plate 2 via these blocks 3a to 3d, and the surface plate 2 is rotated in this state, whereby the work W is polished. At this time, each guide roller 21
It is desirable to move a to 21d to the standby position. In addition, the center liquid supply pipe 15 is provided on the surface plate 2 during the polishing process.
The polishing liquid is supplied through the flow path 16 formed in the first cover member 11 in the radial direction, and the polishing liquid is supplied evenly to the entire surface plate.

When the polishing of the work W is completed, the pressure plates 4 are raised to release the pressure on the work W, and the fourth block 3d near the carry-in / carry-out position P is first taken out by the robot. Other blocks 3
c, 3b, 3a, as in the above loading,
The guide rollers 21a to 21d are alternately moved to the standby position and the support position to move one position by one position, and are sequentially sent to the carry-in / carry-out position P to be taken out. Even when the workpiece W is unloaded, the central liquid supply pipe 1
It is desirable to perform the work while supplying the rinse liquid onto the surface plate 2 through 5. Also, the points that the blocks 3a to 3d waiting for unloading are forcibly driven and rotated by the idle rollers 9a to 9d at the respective supporting positions, which is the same as at the time of loading.

Thus, at the time of loading and unloading the work W, the blocks 3a to 3d waiting on the surface plate are forcibly rotated by the center roller 8 via the idle rollers 9a to 9d. Therefore, especially when unloading after polishing, surface plate 2
It is possible to prevent the occurrence of minute scratches due to the upper polishing liquid flowing appropriately and the work W that has been mirror-polished and the surface plate 2 rubbing against each other.

Further, since the center roller 8 is fixed to the surface plate 2 and is configured to rotate integrally with the surface plate 2, a dedicated drive mechanism is required to drive the center roller 8. In addition, there is an advantage that the structure is simple and the manufacturing cost is low. Moreover, since the center roller 8 and the respective blocks 3 are prevented from coming into direct contact with each other and are brought into contact with each other through the idle rollers 9, the center roller 8 is not damaged by the contact with the blocks 3. Even if the idle roller 9 is damaged, you only have to replace it and it is a big and expensive center roller 8.
There is also an advantage that the structure is simple and the durability is excellent because it is not necessary to replace.

[0027]

As described above, according to the present invention, a drive mechanism dedicated to driving the center roller is not required, and
It is possible to obtain a block forced drive type single-side polishing machine which has a simple structure and is excellent in durability, in which direct contact between the center roller and each block is prevented so that the center roller is not damaged.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of a single-side polishing apparatus according to the present invention.

FIG. 2 is a plan view of a main part schematically showing the structure around a surface plate of the polishing apparatus of FIG.

FIG. 3 is a cross-sectional view of essential parts showing a related configuration of a center roller and an idle roller.

FIG. 4 is an enlarged side view of a main part of FIG.

5A to 5F are explanatory views showing the first half of the process of positioning the block.

6A to 6E are explanatory views showing the latter half of the step of positioning a block.

[Explanation of symbols]

W work 2 surface plate 3,3a-3d blocks 8 center roller 8a cone part 8b Flat part 9, 9a-9d idle rollers 11 First cover member 12 Second cover member 15 Liquid supply pipe 16 channels 21a-21d guide roller

Claims (3)

[Claims] 1. A surface plate that is driven and rotated by a drive source, and a plurality of circular plates that are supplied and arranged at equal intervals around the center of rotation of the surface plate when polishing the work and press the held work against the surface plate. Block, one center roller installed on the center of the upper surface of the surface plate so as to rotate together with the surface plate, and so as to contact both the center roller and the block around the center roller, etc. Arranged to be rotatable at intervals, the idler rollers are driven to rotate around their own axis in a fixed position by the rotation of the center roller, and freely rotatable to a position corresponding to each idle roller around the surface plate. And a supporting position for supporting the block in contact with the block on the surface plate and in contact with the idle roller, and separating the block from the block. And a plurality of guide rollers that are movable between a standby position that allows the block to move by rotation of the surface plate, and a block forced-drive single-side polishing apparatus. 2. The center roller has a conical portion located in the center and an annular flat portion surrounding the conical portion, and the idler rollers are in contact with the outer peripheral surface of the flat portion. The single-sided polishing device according to claim 1, wherein 3. A first cover member, which covers the upper portion of the center roller and rotates together with the center roller, and a second non-rotating second cover member, which covers the upper portion of the center roller, in the central portion of the surface plate. A cover member, the idle rollers are rotatably attached to the second cover member, and the center of the first cover member and the second cover member has a supply liquid for supplying a polishing liquid. The pipe is installed so as to face the center of the upper surface of the center roller, and a flow path for guiding the polishing liquid supplied from the liquid supply pipe onto the surface plate is radially provided between the center roller and the first cover member. The single-sided polishing apparatus according to claim 1 or 2, wherein the single-sided polishing apparatus is provided.