JP2001030161A - Carrier for polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent polishing of works always at a constant position and to improve flatness by pressing the works held by a carrier onto a surface plate while eccentrically rotating the works. SOLUTION: A head 18 is lowered down to a rotating surface plate 12 while rotating the head. A wafer W held by the head 18 is pressed onto a polishing cloth 16, and the surface to be polished of the wafer W is polished receiving a pressure and a relative speed. Because the wafer W held by the head 18 is put in an eccentric hole 28A of a carrier 26A, the carrier 26A is rotated about the center O of the carrier 26A to eccentrically rotate the wafer W. Therefore, the wafer W is pressed onto the polishing cloth 16 with its reciprocation and thereby polishing always at a same position is prevented. As a result, a polishing condition is uniformized for the wafer W to improve flatness of the wafer W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier for a polishing apparatus, and more particularly to a carrier for a polishing apparatus such as a lapping apparatus or a polishing apparatus used in a semiconductor wafer manufacturing process.

[0002]

2. Description of the Related Art A polishing apparatus such as a lapping apparatus or a polishing apparatus used in a semiconductor wafer manufacturing process fixes a wafer to a head and presses the wafer against a rotating surface plate to perform polishing.

However, when the wafer is polished in this manner, the wafer is always polished at a fixed position. For example, if the surface plate is not uniform, the flatness of the processed wafer is reduced. is there.

Therefore, conventionally, polishing was performed while oscillating a head or a surface plate, thereby equalizing the polishing conditions for the wafer and improving the flatness of the wafer.

[0005]

However, in the case of the conventional method of polishing while swinging the wafer,
A swing mechanism must be separately installed in the processing device, and there is a disadvantage that the device becomes large and complicated.

The present invention has been made in view of such circumstances, and has as its object to provide a carrier for a polishing apparatus capable of improving the flatness of a wafer with a simple configuration.

[0007]

The invention according to claim 1 is
In order to achieve the object, in a carrier of a polishing apparatus that holds a work to be polished by being pressed against a surface plate in a hole, the hole is formed to have substantially the same diameter as the outer diameter of the work. , Formed at a position eccentric with respect to the center of the carrier.

According to the present invention, the work held by the carrier is pressed against the surface plate while rotating eccentrically by pressing the work surface against the surface plate while rotating the carrier. This prevents the work from being constantly polished at a fixed position, and improves the flatness.

According to a second aspect of the present invention, there is provided a carrier of a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, in order to achieve the above object. The workpiece is formed in a hole shape, and the work is movably held in the hole.

According to the present invention, the work held by the carrier is pressed against the surface plate while moving in the hole. Thereby, it is prevented that the polishing is always performed at a fixed position, and the flatness is improved.

According to a third aspect of the present invention, there is provided a carrier for a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, wherein the hole has an elliptical shape. The work is held movably in the hole.

According to the present invention, the work held by the carrier is pressed against the surface plate while moving in the hole. Thereby, it is prevented that the polishing is always performed at a fixed position, and the flatness is improved.

According to a fourth aspect of the present invention, there is provided a carrier for a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, wherein the hole has a cross shape. The work is held movably in the hole.

According to the present invention, the work held by the carrier is pressed against the surface plate while moving in the hole. Thereby, it is prevented that the polishing is always performed at a fixed position, and the flatness is improved.

According to a fifth aspect of the present invention, in order to achieve the above object, in the carrier of the polishing apparatus according to the second, third or fourth aspect, the center of the hole is positioned with respect to the center of the carrier. It is characterized in that it is formed at an eccentric position.

According to the present invention, the work held by the carrier is pressed against the surface plate while moving in the hole while being eccentrically rotated. Thereby, it is prevented that polishing is always performed at a fixed position, and the flatness is improved.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a carrier of a polishing apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a front view of a wafer single-side polishing apparatus using a carrier according to the present invention.

As shown in FIG. 1, the single-side polishing apparatus 10 has a surface plate 12 having a flat surface. A rotating shaft 14 that is driven by rotating means (not shown) and rotates is connected to the lower surface of the surface plate 12 coaxially.
A polishing cloth 16 is adhered to the upper surface of 2. A predetermined amount of abrasive (slurry) is dropped onto the polishing cloth 16 from an abrasive (slurry) supply pipe (not shown) provided above the surface plate 12.

A head 18 for holding a wafer W is provided above the surface plate 12. The head 18 is formed in a disk shape, and a rotating shaft 20 that is driven by rotating means (not shown) to rotate and is driven by lifting means (not shown) to move up and down is connected to the upper surface coaxially. A correction ring 22 is provided on the lower surface of the head 18 along the outer peripheral edge of the head 18. A backing pad 24 is attached to the inside of the correction ring 22, and a carrier 26A is attached to the lower surface of the backing pad 24. The wafer W is inserted into a hole 28A formed inside the carrier 26A and held by the head 18.

Here, the carrier 26A is formed in a disk shape as shown in FIG. The hole 28A is formed in a circular shape slightly larger than the outer diameter of the wafer W to be held, and is formed at a position eccentric by a predetermined amount with respect to the center O of the carrier 26A.

The operation of the single-side polishing apparatus 10 constructed as described above is as follows.

A rotating means (not shown) is driven to rotate the platen 12, and an abrasive is supplied onto the polishing pad 16 from an abrasive supply pipe (not shown). Then, the head 18 is lowered with respect to the rotating platen 12 while rotating. As a result, the wafer W held by the head 18 is pressed against the polishing pad 16, and the polished surface of the wafer W is polished by receiving the pressure and the relative speed.

Here, since the wafer W held by the head 18 is placed in the eccentric hole 28A of the carrier 26A, when the carrier 26A is rotated around the center O of the carrier 26A as a rotation center, the wafer W becomes It will rotate eccentrically. Thereby, the wafer W is placed on the polishing pad 16.
, While being reciprocated, and is prevented from being constantly polished at the same position. As a result, the wafer W
Is made uniform, and the flatness of the wafer W is improved.

FIG. 3 is a plan sectional view showing the structure of the carrier according to the second embodiment of the present invention.

As shown in the figure, a hole 26B is formed in a long hole shape in the carrier 26B of the second embodiment.
The hole 28B is formed concentrically with the center O of the carrier 26B, and is formed slightly larger than the diameter of the wafer W held by the width. Further, the radius of the arc-shaped portions at both ends is formed slightly larger than the radius of the wafer W to be held.

According to the carrier 26B of the second embodiment configured as described above, the wafer W held by the carrier 26B can move freely in the hole 28B. That is, the wafer W held by the carrier 26B is
6, the wafer W is polished while moving randomly in the hole 28B of the carrier 26B when the carrier 26B is rotated about the center O of the carrier 26B as a rotation center. Thereby, the wafer W can be prevented from being polished at the same position, and the flatness of the wafer W can be improved.

In this embodiment, the hole 28B is formed concentrically with the center O of the carrier 26B. However, as in the carrier of the first embodiment described above, the hole 28B is formed on the carrier 2B.
It may be formed at a position eccentric with respect to the center O of 6B.

Further, in the present embodiment, the diameter of the wafer W for holding the size of the hole 28B is slightly larger than the diameter of the wafer W, but the present invention is not limited to this. However,
If the gap between the wafer W and the hole 28B becomes too large,
When the peripheral edge of the wafer W comes into contact with the peripheral edge of the hole 28B, the peripheral edge of the wafer W may be chipped or the pressure applied to the wafer W may be non-uniform. Is preferred.

Further, in the present embodiment, the side edge of the hole 28 is formed in a straight line, but may be formed in an arc shape with a rounded outside.

FIG. 4 is a plan sectional view showing the configuration of the third embodiment of the carrier according to the present invention.

As shown in the figure, the carrier 26C of the third embodiment has a hole 28C formed in an elliptical shape. The hole 28C is formed concentrically with the center O of the carrier 26C, and is formed to be larger than the diameter of the wafer W held by the short axis.

According to the carrier 26C of the third embodiment configured as described above, similarly to the carrier 26B of the second embodiment described above, the wafer W held by the carrier 26C is placed in the hole 28C. Can be moved freely.

However, in the case of the carrier 26C of the present embodiment, the wafer W can also move in the short axis direction of the hole 28, so that more random movement is possible. Thereby, the polishing conditions for the wafer W are made more uniform, and the flatness of the wafer W is improved.

In the present embodiment, the hole 28C is formed concentrically with the center O of the carrier 26C.
It may be formed at a position eccentric to the center O of 6C.

In this embodiment, the diameter of the wafer W holding the size of the hole 28C is slightly larger than the diameter of the wafer W. However, the present invention is not limited to this. However,
If the gap between the wafer W and the hole 28C becomes too large,
When the peripheral edge of the wafer W comes into contact with the peripheral edge of the hole 28C, the peripheral edge of the wafer W is chipped or the pressure applied to the wafer W becomes non-uniform, so that, as in the second embodiment described above, It is preferable to set the size appropriately in consideration of this point.

FIG. 5 is a sectional plan view showing the configuration of the fourth embodiment of the carrier according to the present invention.

As shown in the figure, the carrier 26D of the fourth embodiment has a hole 28D formed in a cross shape.
The hole 28D is formed concentrically with the center O of the carrier 26D, and is formed slightly larger than the diameter of the wafer W held by the width. Each corner is formed in an arc shape.

According to the carrier 26D of the third embodiment configured as described above, similarly to the carriers of the second and third embodiments described above, the wafer W held by the carrier 26D has a hole. It can move freely within 28D. In this case, the wafer W can move in the hole 28 in four directions, and can move more randomly. Thereby, the wafer W
Are made more uniform, and the flatness of the wafer W is improved.

In this embodiment, the hole 28D is formed concentrically with the center O of the carrier 26D. However, like the carrier 26A of the first embodiment, the hole 28D is formed at the center O of the carrier 26D. It may be formed at a position eccentric to the eccentricity.

In this embodiment, the diameter of the wafer W holding the width of the hole 28D is slightly larger than the diameter of the wafer W. However, the present invention is not limited to this. However, if the gap between the wafer W and the hole 28D is too large, when the peripheral edge of the wafer W contacts the peripheral edge of the hole 28D, the peripheral edge of the wafer W is chipped or the pressure applied to the wafer W becomes uneven. Therefore, similarly to the above-described second embodiment, it is preferable to set an appropriate width in consideration of this point.

In the series of embodiments described above, the carrier according to the present invention is applied to a single-side polishing apparatus, but the carrier according to the present invention is applied to a double-side polishing apparatus shown in FIG. 30 is also applicable. As shown in the figure, this double-side polishing apparatus 30 sandwiches a wafer W between an upper surface plate 32 and a lower surface plate 34, applies pressure to the upper surface plate 32 while interposing an abrasive, and The platen 32 and the lower platen 34 are rotated. Thereby, the upper surface and the lower surface of the wafer W are polished simultaneously.

At this time, the wafer W is loaded on the carrier 3
6 and revolves while rotating between the upper surface plate 32 and the lower surface plate 34. That is, as shown in FIG. 7, the carrier 36 has a planetary gear 40 formed on the outer periphery thereof. The planetary gear 40 is connected to the internal gear 42 located on the outer periphery of the lower platen 34, And is engaged with the sun gear 44 fixed thereto. Therefore, when the lower platen 34 is rotated, the carrier 36 revolves around the sun gear 44 while rotating by the action of each gear.

In the above-described series of embodiments, the pressure applied to the wafer W is not particularly described, but the pressure is set to such a degree that the wafer W can move in the hole of the carrier. The pressure applied to the wafer W is
Assuming that the pressure is uniformly applied to the entire wafer, the pressing method is not particularly limited.

The thickness of the carrier is set to an appropriate thickness in consideration of the compression ratio of the backing pad 24 and the thickness of the wafer W.

Further, the material of the backing pad 24 is preferably a material having a small friction coefficient so that the held wafer W can move smoothly, and a groove may be formed in the backing pad 24 if necessary.

Although the carrier is attached to the backing pad 24 in the present embodiment, it may be attached directly to the head 18.

As for the material of the carrier, cracking and chipping can be prevented when the wafer W comes into contact (for example, glass fiber reinforced epoxy resin, stainless steel, polytetrafluoroethylene, etc.). Is preferably smoothed (reduced surface roughness).

[0049]

According to the present invention, it is possible to prevent the work from being polished at a fixed position at all times, so that the polishing conditions for the work can be made uniform and the flatness of the work can be improved.

[Brief description of the drawings]

FIG. 1 is a front view of a single-side polishing apparatus.

FIG. 2 is a cross-sectional plan view showing the configuration of the first embodiment of the carrier according to the present invention.

FIG. 3 is a sectional plan view showing the configuration of a carrier according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional plan view showing the configuration of a third embodiment of the carrier according to the present invention.

FIG. 5 is a cross-sectional plan view showing a configuration of a fourth embodiment of the carrier according to the present invention.

FIG. 6 is a front view of a double-side polishing apparatus.

FIG. 7 is a plan view showing a configuration of a main part of the double-side polishing apparatus.

[Explanation of symbols]

10: single-side polishing machine, 12: surface plate, 16: polishing cloth,
18 head, 22 correction ring, 24 backing pad, 26A-26D carrier, 28A-28D
Holes, 30: Double-side polishing machine, 32: Upper platen, 34: Lower platen, 36: Carrier, 38: Hole, 40: Planetary gear, 4
2: Internal gear, 44: Sun gear, W: Wafer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3C058 AA07 AA16 AB04 AB06 AB08 CB01 DA06 DA09 DA17

Claims (5)

[Claims] 1. A carrier of a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, wherein the hole is formed to have substantially the same shape as the outer shape of the work, and a center of the carrier is provided. A carrier for a polishing apparatus, wherein the carrier is formed at an eccentric position with respect to the carrier. 2. A carrier of a polishing apparatus for holding a work to be polished by being pressed against a surface plate into a hole, wherein the hole is formed in a long hole shape, and the work is movable in the hole. A carrier for a polishing apparatus characterized by being held in a carrier. 3. A carrier of a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, wherein the hole is formed in an elliptical shape, and the work is movable in the hole. A carrier for a polishing apparatus characterized by being held. 4. A carrier of a polishing apparatus for holding a work to be polished by being pressed against a surface plate in a hole, wherein the hole is formed in a cross shape, and the work is movable in the hole. A carrier for a polishing apparatus characterized by being held. 5. The carrier according to claim 2, wherein a center of the hole is formed at a position eccentric with respect to a center of the carrier.