JPH06226616A - Disk modifying method and device for plane polisher - Google Patents

Abstract

PURPOSE:To modify the flatness of disks in a plane polisher with high precision by using a simple mechanism. CONSTITUTION:An internally toothed gear 4 in a plane polisher is engaged with an annular, large modifying carrier 5 with the outer diameter smaller than that of a disk 2 and the inner diameter larger than that of the disk and engaged with a small modifying carrier 6 between a sun gear 3 and the large modifying carrier 5 in a hole 5c in the large modifying carrier. Between the upper and lower disks, the small modifying carrier 6 is planetary-motioned with the sun gear 3 and the internally toothed gear 4 and the large modifying carrier 5 is eccentrically oscillated to modify the flatness of both disks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for correcting the flatness of upper and lower surface plates in a flat surface polishing apparatus for polishing both surfaces of a work such as a semiconductor wafer or a magnetic disk substrate. .

[0002]

2. Description of the Related Art A carrier for holding a work is meshed with a sun gear and an internal gear, and the work held by the carrier is sandwiched from both sides by upper and lower surface plates and polished while the carrier makes a planetary motion of the carrier. A flat-polishing device for performing this is known.

In such a surface polishing apparatus, the surface plate is worn due to the processing, and the flatness of the surface plate is deteriorated to reduce the machining accuracy of the work. Therefore, the flatness of the surface plate is always managed and corrected as necessary. It is necessary to do
Conventionally, various correction methods have been proposed.

For example, in Japanese Patent Laid-Open No. 60-16363, a plurality of small correction carriers having the same size as the above-mentioned carrier for holding a work are used, and these correction carriers are used as a sun gear and an internal gear. Although it is disclosed that the upper and lower surface plates are corrected by engaging with each other and performing a planetary motion with both gears, since each correction carrier is small and independent, the surface plate after the correction is There is a drawback that swelling is likely to occur and the correction accuracy is not good.

On the other hand, in Japanese Utility Model Laid-Open No. 64-50048, a single correction medium surface plate having a diameter slightly smaller than the surface plate is used, and the medium surface plate is eccentrically rocked and rotated. It is disclosed that the entire surface is slid with the surface plate. According to this, compared to the above-mentioned conventional example using a plurality of small size correction carriers, undulation is less likely to occur on the surface plate surface, and therefore the correction accuracy is high. There is an advantage.

However, the above-mentioned correction intermediate surface plate includes a support member that rotates while keeping the sun gear concentric, a pair of upper and lower correction intermediate surface plate bodies swingably supported by the support member,
An eccentric drive gear that eccentrically swings and rotates the intermediate platen body by planetary motion by meshing with a sun gear and an internal gear.
It is composed of a number of members such as a support shaft that regulates the movement between the support member and the intermediate platen body, a bearing that supports the rotating portion of the eccentric drive gear and the support shaft, and therefore the structure is very complicated, Manufacturing and handling are troublesome and expensive, and there is a problem that the eccentric oscillating rotation of the intermediate platen becomes unstable due to the wear of the bearing, and the polishing accuracy is reduced.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a correction method and apparatus which can easily and accurately correct a surface plate.

[0008]

In order to solve the above-mentioned problems, the correction method of the present invention provides a sun gear and an internal gear that mesh with a carrier for holding a work to make the carrier make a planetary motion, and the carrier is held by the carrier. In the above-mentioned internal gear, which has a ring-shaped upper and lower platen for sandwiching and polishing the formed work, the outer diameter is smaller than the outer diameter of the platen and the inner diameter is larger than the inner diameter of the platen. The annular large-diameter correction carrier is meshed with the small-diameter correction carrier between the sun gear and the large-diameter correction carrier in the inner hole of the large-diameter correction carrier, and the small-diameter correction carrier is provided between the upper and lower surface plates. It is characterized in that the large-diameter correction carrier is eccentrically rocked and rotated while the planetary motion is performed.

Further, according to the correction device of the present invention, a sun gear and an internal gear that mesh with a carrier for holding a work to make the carrier carry out a planetary motion, and a circle for sandwiching and polishing a work held by the carrier from both sides. An apparatus for correcting the flatness of both surface plates of a flat surface polishing device having annular upper and lower surface plates, wherein the outer diameter is smaller than the outer diameter of the surface plate and the inner diameter is larger than the inner diameter of the surface plate. A large-diameter correction carrier that has an annular shape and has inner and outer gears, respectively, and has a large-diameter correction carrier that meshes with the internal gear on the outer-circumferential gears, and a disk shape that has a gear on the outer circumference. At a sun gear and a small diameter correction carrier which meshes with a gear on the inner circumference of the large diameter correction carrier. The correction surface of the large diameter correction carrier may be provided with an annular recess.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 show the essential parts of a flat polishing apparatus in a state where the flatness of the upper and lower surface plates 1 and 2 is corrected, and this flat polishing apparatus has an annular shape similar to a known flat polishing apparatus. Which have the upper and lower surface plates 1 and 2 and the sun gear 3 and the internal gear 4 which are held by a carrier (not shown) which meshes with the sun gear 3 and the internal gear 4 to make a planetary motion. A polishing tool (not shown) is sandwiched between the upper and lower surface plates 1 and 2 from both sides to be ground. When the upper and lower surface plates 1 and 2 are to be repaired, the carrier for holding the work is taken out and illustrated. As described above, the large diameter correction carrier 5 and the small diameter correction carrier 6 are mounted.

The large-diameter correction carrier 5 has an annular shape whose outer diameter is smaller than the outer diameter of the surface plates 1 and 2 and whose inner diameter is larger than the inner diameter of the surface plates, and the front and back surfaces of the large-diameter correction carrier 5 are the upper and lower surface plates 1 and 2. Gears 5a and 5b are formed on the inner and outer circumferences of the ring, respectively. The gears 5a on the outer circumference mesh with the internal gear 4 so that the upper and lower platens 1 and 2 are brought into contact with each other. It is arranged so as to be eccentric with respect to these surface plates. At this time, the gear 5b on the inner circumference of the large diameter correction carrier 5 is not meshed with the sun gear 3. Further, a plurality of holes 7 are bored in the large-diameter correction carrier 5, and these holes serve as escape holes for abrasive grains at the time of correction.

On the other hand, the small-diameter correcting carrier 6 has a disk shape having both front and back surfaces as correcting surfaces for contacting the upper and lower surface plates 1 and 2, and a gear 6a is provided on the outer periphery thereof. In the inner hole 5c of the carrier 5, on the line connecting the meshing point P of the large diameter correction carrier 5 and the internal gear 4 and the center O of the sun gear 3, the inner diameter of the sun gear 3 and the large diameter correction carrier 5 is It is arranged so as to mesh with both the peripheral gear 5b. The small diameter correction carrier 6 can also be provided with an escape hole for abrasive grains.

Now, in FIG. 2, when the sun gear 3 is rotated at a desired speed in the direction of arrow a, the small diameter correction carrier 6 revolves around the sun gear 3 in the direction of arrow c while rotating in the direction of arrow b. The large diameter correction carrier 5 is the internal gear 4
While moving eccentrically by changing the meshing position with and in the direction of arrow d, arrow e at a speed based on the number of teeth difference with internal gear 4
Rotate in the direction. As a result, the small diameter correction carrier 6 slides on the upper and lower surface plates 1 and 2 while performing a planetary motion around the sun gear 3, and the large diameter correction carrier 5 rotates eccentrically with respect to the sun gear 3. The flatness of the upper and lower surface plates 1 and 2 is corrected by completely sliding on the upper and lower surface plates 1 and 2.
In this case, the large and small correction carriers 5 and 6 having different sizes and movement loci slide together with the surface plates 1 and 2,
The same effect as in the case where the three-sided sliding is performed can be obtained, which makes it possible to obtain a surface plate with less waviness and high flatness.

In the above description of the correction operation, the case where only the sun gear 3 is rotated has been described as an example for the sake of clarity. However, the internal gear 4 may be rotated at the same time. It is necessary to set the rotation direction and the rotation speed of the internal gear 3 and the internal gear 4 within a range in which the correction carriers 5 and 6 can perform the correction operation. Of course, the upper and lower surface plates 1 and 2 may be rotated in the same direction or in opposite directions at a desired speed at the time of the above correction.

FIG. 3 shows a different configuration example of the large-diameter correction carrier 5. This large-diameter correction carrier 5 is provided with an annular recess 8 on one of the correction surfaces.

[0016]

As described above, according to the present invention, the flatness of the surface plate can be easily and accurately corrected by using only two types of correction carriers, large and small. Also, since the two correction carriers are independent of each other and are used by being meshed with each other or with the sun gear and the internal gear, each member can be used via bearings or the like like a conventional correction intermediate surface plate. The structure is simple as compared with those connected to each other, and there is no problem that the eccentric oscillating rotation becomes unstable due to wear of the bearing, and the correction operation can be stabilized.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.

FIG. 2 is a plan view showing a state in which an upper surface plate in FIG. 1 is removed.

FIG. 3 is a cross-sectional view showing a different structure example of a large diameter correction carrier.

[Explanation of symbols]

1 Upper surface plate 2 Lower surface plate 3 Sun gear 4 Internal gear 5 Large diameter correction carrier 6 Small diameter correction carrier 5c Inner hole 8 Recess

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[Procedure amendment]

[Submission date] December 27, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for correcting the flatness of upper and lower surface plates in a flat surface polishing apparatus for polishing both surfaces of a work such as a semiconductor wafer or a magnetic disk substrate. .

[0002]

2. Description of the Related Art A carrier for holding a work is meshed with a sun gear and an internal gear, and the work held by the carrier is sandwiched from both sides by upper and lower surface plates and polished while the carrier makes a planetary motion of the carrier. A flat-polishing device for performing this is known.

In such a surface polishing apparatus, the surface plate is worn due to the processing, and the flatness of the surface plate is deteriorated to reduce the machining accuracy of the work. Therefore, the flatness of the surface plate is always managed and corrected as necessary. It is necessary to do
Conventionally, various correction methods have been proposed.

For example, in Japanese Patent Laid-Open No. 60-16363, a plurality of small correction carriers having the same size as the above-mentioned carrier for holding a work are used, and these correction carriers are used as a sun gear and an internal gear. Although it is disclosed that the upper and lower surface plates are corrected by engaging with each other and performing a planetary motion with both gears, since each correction carrier is small and independent, the surface plate after the correction is There is a drawback that swelling is likely to occur and the correction accuracy is not good.

On the other hand, in Japanese Utility Model Laid-Open No. 64-50048, a single correction medium surface plate having a diameter slightly smaller than the surface plate is used, and the medium surface plate is eccentrically rocked and rotated. It is disclosed that the entire surface is slid with the surface plate. According to this, compared to the above-mentioned conventional example using a plurality of small size correction carriers, undulation is less likely to occur on the surface plate surface, and therefore the correction accuracy is high. There is an advantage.

However, the above-mentioned correction intermediate surface plate includes a support member that rotates while keeping the sun gear concentric, a pair of upper and lower correction intermediate surface plate bodies swingably supported by the support member,
An eccentric drive gear that eccentrically swings and rotates the intermediate platen body by planetary motion by meshing with a sun gear and an internal gear.
It is composed of a number of members such as a support shaft that regulates the movement between the support member and the intermediate platen body, a bearing that supports the rotating portion of the eccentric drive gear and the support shaft, and therefore the structure is very complicated, Manufacturing and handling are troublesome and expensive, and there is a problem that the eccentric oscillating rotation of the intermediate platen becomes unstable due to the wear of the bearing, and the polishing accuracy is reduced.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a correction method and apparatus which can easily and accurately correct a surface plate.

[0008]

In order to solve the above-mentioned problems, the correction method of the present invention includes a sun gear and an internal gear that mesh with a carrier for holding a workpiece to make the carrier make a planetary motion, and the carrier is held by the carrier. In the above-mentioned internal gear of a plane polishing device equipped with upper and lower circular platens that sandwich and polish a workpiece from both sides, the outer ring has an outer diameter smaller than the outer diameter of the platen and an inner diameter larger than the inner diameter of the platen. Of the large diameter correction carrier, the small diameter correction carrier is meshed between the sun gear and the large diameter correction carrier in the inner hole of the large diameter correction carrier, and the small diameter correction carrier is planet-moved between the upper and lower surface plates. The large diameter correction carrier is eccentrically rocked and rotated.

Further, the correction device of the present invention comprises a sun gear and an internal gear that mesh with a carrier for holding a workpiece to make the carrier make a planetary motion, and an annular ring for sandwiching and polishing the workpiece held by the carrier from both sides. An apparatus for correcting the flatness of both surface plates of a flat polishing device having upper and lower surface plates, wherein the outer diameter is smaller than the outer diameter of the surface plate and the inner diameter is larger than the inner diameter of the surface plate. In addition, it has a large-diameter correction carrier that has gears on the inner and outer circumferences, and that has gears on the outer circumference, and a gear on the outer circumference. The small-diameter correction carrier meshes with a gear and an inner peripheral gear of the large-diameter correction carrier. The correction surface of the large diameter correction carrier may be provided with an annular recess.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 show the essential parts of a flat polishing apparatus in a state where the flatness of the upper and lower surface plates 1 and 2 is corrected, and this flat polishing apparatus has an annular shape similar to a known flat polishing apparatus. Which have the upper and lower surface plates 1 and 2 and the sun gear 3 and the internal gear 4 which are held by a carrier (not shown) which meshes with the sun gear 3 and the internal gear 4 to make a planetary motion. (Not shown) is sandwiched between the upper and lower surface plates 1 and 2 for polishing. When the upper and lower surface plates 1 and 2 are to be repaired, the carrier for holding the work is taken out, and as shown in the drawing. The large diameter correction carrier 5 and the small diameter correction carrier 6 are mounted.

The large-diameter correction carrier 5 has an annular shape whose outer diameter is smaller than the outer diameter of the surface plates 1 and 2 and whose inner diameter is larger than the inner diameter of the surface plates, and the front and back surfaces of the large-diameter correction carrier 5 are the upper and lower surface plates 1 and 2. Gears 5a and 5b are formed on the inner and outer circumferences of the ring, respectively. The gears 5a on the outer circumference mesh with the internal gear 4 so that the upper and lower platens 1 and 2 are brought into contact with each other. It is arranged so as to be eccentric with respect to these surface plates. At this time, the gear 5b on the inner circumference of the large diameter correction carrier 5 is not meshed with the sun gear 3. Further, a plurality of holes 7 are bored in the large-diameter correction carrier 5, and these holes serve as escape holes for abrasive grains at the time of correction.

On the other hand, the small-diameter correcting carrier 6 has a disk shape having both front and back surfaces as correcting surfaces for contacting the upper and lower surface plates 1 and 2, and a gear 6a is provided on the outer periphery thereof. In the inner hole 5c of the carrier 5, on the line connecting the meshing point P of the large diameter correction carrier 5 and the internal gear 4 and the center O of the sun gear 3, the inner diameter of the sun gear 3 and the large diameter correction carrier 5 is It is arranged so as to mesh with both the peripheral gear 5b. The small diameter correction carrier 6 can also be provided with an escape hole for abrasive grains.

Now, in FIG. 2, when the sun gear 3 is rotated at a desired speed in the direction of arrow a, the small diameter correction carrier 6 revolves around the sun gear 3 in the direction of arrow c while rotating in the direction of arrow b. The large diameter correction carrier 5 is the internal gear 4
While moving eccentrically by changing the meshing position with and in the direction of arrow d, arrow e at a speed based on the number of teeth difference with internal gear 4
Rotate in the direction. As a result, the small diameter correction carrier 6 slides on the upper and lower surface plates 1 and 2 while performing a planetary motion around the sun gear 3, and the large diameter correction carrier 5 rotates eccentrically with respect to the sun gear 3. The flatness of the upper and lower surface plates 1 and 2 is corrected by completely sliding on the upper and lower surface plates 1 and 2.
In this case, the large and small correction carriers 5 and 6 having different sizes and movement loci slide together with the surface plates 1 and 2,
The same effect as in the case where the three-sided sliding is performed can be obtained, which makes it possible to obtain a surface plate with less waviness and high flatness.

In the above description of the correction operation, the case where only the sun gear 3 is rotated has been described as an example for the sake of clarity. However, the internal gear 4 may be rotated at the same time. It is necessary to set the rotation direction and the rotation speed of the internal gear 3 and the internal gear 4 within a range in which the correction carriers 5 and 6 can perform the correction operation. Of course, the upper and lower surface plates 1 and 2 may be rotated in the same direction or in opposite directions at a desired speed at the time of the above correction.

FIG. 3 shows a different configuration example of the large-diameter correction carrier 5. This large-diameter correction carrier 5 is provided with an annular recess 8 on one of the correction surfaces.

Next, a correction test of the surface plate according to the present invention will be described. The experiment was carried out by using a device as shown in FIGS. 1 and 2, and by a three-way rotation system in which the upper platen, the sun gear, and the internal gear were rotated while supplying GC2500 as abrasive grains. At this time, the rotation direction of the large diameter correction carrier may be either forward or reverse, but here, by making the angular velocity of the sun gear larger than the angular velocity of the internal gear,
It was set to the same clockwise direction (normal rotation) as when machining the workpiece . So
The results are shown in Table 1. On the other hand, in order to obtain a comparative example, four
Surface plate repair by conventional method using small diameter correction carrier
Did the positive. Rotation direction of small diameter correction carrier at this time
Reduces the angular velocity of the sun gear to less than that of the internal gear.
The counterclockwise direction is the
(Reverse) The results are shown in Table 2. In these tables
When the flatness is minus, the surface plate is concave, and when the flatness is convex,
It is in a state.

As can be seen from these results, the present invention
In addition, fix the flatness of the lower surface plate from +6 μm to 0 μm.
While the correction time required to correct is about 8 hours,
In the conventional method, the flatness of the lower surface plate is changed from +7 μm to +2 μm.
It takes about 18 hours to correct up to m.
The invention requires a shorter correction time of about 10 hours. In addition,
The above-mentioned correction of the surface plate is performed 4 times to rotate the lower surface plate as well.
Although it can be performed by the transfer method, here
To reduce the shake of the board and improve the correction accuracy as much as possible
Therefore, the three-way rotation method with the lower surface plate fixed was performed.

[0018]

[Table 1]

[0019]

[Table 2]

[0020]

As described above, according to the present invention, the flatness of the surface plate can be easily and accurately corrected by using only two types of correction carriers, large and small. Also, since the two correction carriers are independent of each other and are used by being meshed with each other or with the sun gear and the internal gear, each member can be used via bearings or the like like a conventional correction intermediate surface plate. The structure is simple as compared with those connected to each other, and there is no problem that the eccentric oscillating rotation becomes unstable due to wear of the bearing, and the correction operation can be stabilized.

Claims (3)

[Claims] 1. A sun gear and an internal gear that mesh with a carrier for holding a work to make the carrier carry out a planetary motion, and annular upper and lower platens for sandwiching and polishing the work held by the carrier from both sides. A ring-shaped large-diameter correction carrier having an outer diameter smaller than the outer diameter of the surface plate and an inner diameter larger than the inner diameter of the surface plate is meshed with the internal gear of the provided surface polishing device, and the large-diameter correction carrier is By engaging the small-diameter correction carrier between the sun gear and the large-diameter correction carrier in the inner hole, and causing the small-diameter correction carrier to make a planetary motion between the upper and lower surface plates and to eccentrically swing and rotate the large-diameter correction carrier, A method of correcting a surface plate in a flat polishing apparatus, which comprises correcting the flatness of a surface plate. 2. A sun gear and an internal gear that mesh with a carrier for holding a work to make the carrier carry out a planetary motion, and upper and lower annular platens for sandwiching and polishing the work held by the carrier from both sides. An apparatus for correcting the flatness of both surface plates of a provided surface polishing apparatus, which has an annular shape with an outer diameter smaller than the outer diameter of the surface plate and an inner diameter larger than the inner diameter of the surface plate, and A large-diameter correction carrier that has gears on its circumference and a gear on the outer circumference that meshes with the internal gear, and a disk shape that has gears on the outer circumference, and the sun gear and the large-diameter correction gear inside the inner hole of the large-diameter correction carrier. A correction device for a platen in a flat polishing apparatus, comprising a small-diameter correction carrier that meshes with a gear on the inner periphery of the correction carrier. 3. The correction device according to claim 2, wherein the correction surface of the large-diameter correction carrier is provided with an annular recess.