TW201832868A - Carrier for double-sided polishing device - Google Patents

Abstract

The present invention provides a carrier for a double-side polishing apparatus, comprising a carrier member formed with a support hole for supporting a wafer during polishing, and an insert disposed along an inner circumference of the support hole, wherein the carrier member is The uneven portion is periodically formed along the inner circumference of the support hole, and the distance between the centers of the adjacent concave portions in the uneven portion is 10 mm or more and 60 mm or less, and the area of the convex portion in the uneven portion is larger than the area of the cut portion of the concave portion. The insert is periodically formed with a concavo-convex portion on the outer peripheral portion, and the concavo-convex portion of the carrier member formed on the inner circumference of the support hole is fitted to the concavo-convex portion formed on the outer peripheral portion of the insert, whereby the carrier member is provided. The carrier for the double-side polishing apparatus in which the distortion of the peripheral portion (fitting portion) of the support hole is reduced.

Description

Double-sided grinding device carrier

The present invention relates to a carrier for a double-side polishing apparatus which can be used for a double-side polishing apparatus for polishing a wafer on both sides.

Since the double-side polishing apparatus simultaneously polishes both sides of, for example, five wafers in each batch, a carrier for a double-side grinder having the same number of support holes as the number of wafers is provided on the fixed plate. The wafer is supported by the support hole of the carrier, and the polishing cloth provided on the upper and lower fixed plates is inserted into the wafer from both sides, and is polished while supplying the polishing agent on the polishing surface.

A carrier for a double-side polishing apparatus having a carrier member for supporting a support hole of a wafer, usually made of metal. The carrier for the double-side polishing apparatus protects the outer peripheral portion of the wafer from a carrier member made of metal, and has a resin insert on the inner circumference of the wafer support hole. This insert is formed by insert molding or injection molding. The insert is in contact with the outer peripheral portion of the wafer, so the formation of the edge shape of the wafer is important.

When the insert is mounted, in order to prevent the insert from falling off during wafer processing and transportation, a wedge shape is formed on the outer peripheral portion of the insert and the inner peripheral portion of the support hole of the carrier member, and further, The agent is fixed (Patent Document 1).

[Prior Art Document] Patent Document 1: Japanese Patent Laid-Open Publication No. 2000-24912

The wedge shape of the outer peripheral portion of the insert and the inner peripheral portion of the support hole of the carrier member is periodically plural, which may cause distortion during processing of the carrier. Further, there may be a problem that the insert is tightened due to the processing precision when the insert is fitted, and local stress is generated and the periphery of the support hole of the carrier member is twisted. Further, the distortion of the fitting portion around the support hole of the carrier member causes deterioration of the edge shape of the wafer, which causes the carrier member and the insert to be misaligned.

When wafer processing is performed in this state, the polishing cloth is locally deformed, causing deterioration of wafer flatness. Further, although the carrier member and the insert are misaligned, the carrier member and the insert can be corrected to the same height to some extent by grinding, but the distortion of the fitting portion around the support hole of the carrier member cannot be corrected. As a result, the edge shape of the wafer deteriorates due to this distortion. Further, since the degree of deterioration of the shape of the wafer varies depending on the size of the distortion, there is a possibility that the flatness may be uneven between the five-piece carriers. Therefore, in order to suppress the deterioration of the edge shape of the wafer and the unevenness of the flatness between the carriers, it is also required to have a carrier for the double-side polishing apparatus having less distortion of the peripheral portion (fitting portion) of the support hole of the carrier member.

The present invention has been made in view of the above problems, and an object thereof is to provide a carrier for a double-side polishing apparatus which reduces distortion of a peripheral portion (fitting portion) of a support hole of a carrier member.

In order to solve the above problems, the present invention provides a carrier for a double-side polishing apparatus, which is disposed in a double-side polishing apparatus for polishing a wafer on both sides, and includes a support hole formed to support a wafer during polishing. a carrier member and an insert disposed along an inner circumference of the support hole and formed with an inner peripheral portion in contact with an outer peripheral portion of the wafer, wherein the carrier member is an inner circumference period along the support hole Optionally, a concave-convex portion is formed, and a distance between centers of adjacent concave portions in the concave-convex portion is 10 mm or more and 60 mm or less, and an area of the convex portion in the concave-convex portion is smaller than an area of the cutout portion of the concave portion in a planar direction of the carrier member To the extent that the insert is periodically formed with a concavo-convex portion on the outer peripheral portion and fitted to the concavo-convex portion formed on the inner circumference of the support hole, the unevenness of the carrier member formed on the inner circumference of the support hole The portion is fitted to the uneven portion formed on the outer peripheral portion of the insert.

In the case of such a double-side polishing apparatus carrier, the carrier for a double-side polishing apparatus which reduces the distortion of the peripheral portion (fitting portion) of the support hole of the carrier member.

Further, at this time, the shape of the cutout portion of the recess formed in the inner circumference of the support hole of the carrier member is a triangle, a rectangle, a trapezoid, a wedge, a keyhole, a U, and a circle.

In the carrier for a double-side polishing apparatus of the present invention, the shape of the slit portion of the concave portion formed on the inner circumference of the support hole as the carrier member may be as described above.

Further, at this time, in the uneven portion of the carrier mother member formed on the inner circumference of the support hole, the area of the convex portion in the planar direction of the carrier member is 4 times the area of the slit portion of the recess portion. The above is better.

In the case of the carrier for the double-side polishing apparatus, the strength of the convex portion formed on the inner circumference of the support hole of the carrier member is further increased, and the peripheral portion of the support hole of the carrier member is further reduced (the fitting portion) The twisted double-sided polishing apparatus is preferably a carrier.

According to the carrier for the double-side polishing apparatus of the present invention, the strength of the fitting portion of the carrier member formed on the inner circumference of the support hole can be enhanced, and the distortion around the support hole of the carrier member can be reduced. Further, when the wafer is double-sidedly polished by the carrier using such a double-side polishing apparatus, the effect of reducing the distortion around the support hole can be obtained, and the wafer having improved edge flatness and reduced flatness dispersion can be obtained.

As described above, it has been conventionally desired to have a carrier for a double-side polishing apparatus having a less twisted peripheral portion (fitting portion) of a support member of a carrier member.

Further, as a result of intensive studies in order to solve the above problems, the inventors of the present invention found that the distance between the concave portions of the uneven portions formed on the inner circumference of the support hole by the carrier member (that is, the distance between the centers of the adjacent concave portions) is The present invention has been completed by the conventionally known 5 mm or more and less than 10 mm, and expanded to 10 mm or more and 60 mm or less, and can be a carrier having a reduced distortion of the fitting portion of the carrier mother member and the insert member.

That is, the present invention provides a carrier for a double-side polishing apparatus, which is disposed in a double-side polishing apparatus for polishing a wafer on both sides, and includes a carrier member formed with a support hole for supporting the wafer during polishing, And an insert disposed along the inner circumference of the support hole and formed with an inner peripheral portion in contact with the outer peripheral portion of the wafer, wherein the carrier member is periodically formed along an inner circumference of the support hole In the uneven portion, the distance between the centers of the adjacent concave portions in the uneven portion is 10 mm or more and 60 mm or less, and the area of the convex portion in the uneven portion is larger than the area of the cut portion of the concave portion in the planar direction of the carrier member. The insert is periodically formed with a concavo-convex portion at the outer peripheral portion to be fitted to the concavo-convex portion formed on the inner circumference of the support hole, and the concavo-convex portion of the carrier member formed on the inner circumference of the support hole and the insertion portion The uneven portion formed on the outer peripheral portion of the member is fitted.

The carrier for the double-side polishing apparatus of the present invention will be described in detail below.

Fig. 1 shows an example of a carrier for a double-side polishing apparatus of the present invention. The carrier 1 for a double-side polishing apparatus of the present invention is disposed in a double-side polishing apparatus for polishing a wafer on both sides, and has a carrier member 3 formed along a support hole 2 for supporting a wafer during polishing, and along The insert 4 is disposed on the inner circumference of the support hole 2 and is formed with an inner peripheral portion that is in contact with the outer peripheral portion of the wafer.

The carrier member 3 is periodically and continuously formed along the inner circumference of the support hole 2. In the present invention, the distance d between the centers of the adjacent concave portions 5a of the uneven portion 5 of the carrier member 3 is 10 mm or more and 60 mm or less. The area of the convex portion 5b in the uneven portion 5 in the planar direction of the carrier member 3 is larger than the area of the slit portion of the concave portion 5a.

In this manner, the distance d between the centers of the adjacent concave portions 5a of the uneven portion 5 of the carrier member 3 is 10 mm or more and 60 mm or less, and the distance is wider than the conventional one, so as to be a fitting portion of the carrier member 3 and the insert 4. The carrier 1 for the double-sided polishing apparatus with reduced distortion is twisted.

As shown in Fig. 2, in the conventional carrier 10 for a double-side polishing apparatus, in order to surely fit the insert 40 and the carrier member 30, the distance between the centers of the adjacent concave portions 50a in the uneven portion of the carrier member 30 is The wafer diameters are different, but there are relatively narrow intervals of mostly 5 mm to 10 mm (about 9.6 mm at 300 mm diameter). However, such a narrow interval causes partial stress concentration, as shown in FIG. 3, which causes distortion around the support hole of the carrier member 30.

In the present invention, the area of the convex portion 5b of the uneven portion 5 in the planar direction of the carrier member 3 is larger than the area of the slit portion of the concave portion 5a, and is adjacent to the concave portion 5a of the uneven portion 5 of the carrier member 3. The distance d between the centers is expanded to 10 mm or more, whereby the number of the uneven portions 5 is reduced as compared with the conventional one, and the area of the convex portions 5b on the carrier mother side can be relatively enlarged. Thus, by making the interval of the fitting portion wider, the amount of twist around the support hole of the carrier member 3 can be reduced. Further, if d exceeds 60 mm, there is a possibility that the insert 4 is detached from the carrier member 3 in wafer processing. Therefore, in the present invention, d is 60 mm or less. Further, the distance d between the centers of the adjacent concave portions 5a of the uneven portion 5 of the carrier member 3 is preferably 14 mm or more and 50 mm or less, and more preferably 18 mm or more and 30 mm or less.

Here, the relationship between the magnitude of the distance d between the centers of the adjacent concave portions in the uneven portion formed on the inner circumference of the support hole of the carrier member and the distortion of the peripheral portion (fitting portion) of the support hole of the carrier member is as follows. .

Regarding the fitting portion around the support hole of the carrier member for the carrier for the double-side polishing apparatus for polishing the 矽 wafer having a diameter of 300 mm, the carrier at the distance d (9.6 mm) from the center of the conventional adjacent concave portion The amount of twist of the carrier member was used as a reference, and the amount of distortion of the carrier member when the distance d was expanded to 10 times (95.5 mm) was numerically analyzed by a simulation analysis (manufactured by ANSYS Corporation).

The results of the shape of the notched portion of the uneven portion analyzed in a table shape and the state of being circular are shown in FIGS. 4(A) and 4(B). As a result, the distance d between the centers of the concave portions adjacent to the uneven portion of the carrier member is not full, in the case of a trapezoidal shape (Fig. 4(A)) and in the case of a circular shape (Fig. 4(B)). When the thickness is 10 mm, the amount of distortion (deformation rate) is greatly increased as compared with the case of 10 mm or more. On the other hand, if the distance d between the adjacent centers is 10 mm or more, the larger the distance d between the centers of the adjacent concave portions, the smaller the distortion is. The reduction in distortion will gradually become saturated as the interval is enlarged, and the shape of the slit portion will be fixed at a distance of 4 times (d=38.2 mm) or more.

When the shape of the slit portion of the concave portion is a trapezoidal shape, the amount of twist at a distance of 4 times (d = 38.2 mm) when the deformation ratio of the distance between the centers of the conventional adjacent concave portions (d = 9.6 mm) is used as a reference Reduced by 11%. When the notched portion of the concave portion is circular, it is also fixed at a distance of four times or more, and the amount of distortion at the time of the conventional deformation rate is reduced by 6.5%.

Further, in the carrier 1 for a double-side polishing apparatus according to the present invention, the shape of the slit portion of the recess 5a formed in the inner periphery of the support hole of the carrier member 3 is triangular, rectangular, trapezoidal, wedge-shaped, keyhole-shaped, or U-shaped. Any one of the round and the round is preferred. Further, in any of these shapes, as a result of the simulation analysis, the same tendency as described above was found.

Further, in the uneven portion 5 formed on the inner periphery of the support hole 2 of the carrier member 3, the area of the convex portion 5b in the planar direction of the carrier member 3 is preferably 4 times or more the area of the slit portion of the concave portion 5a. . In the case of the carrier 1 for a double-side polishing apparatus, the strength of the convex portion 5b is further improved, and the distortion of the peripheral portion (fitting portion) of the support hole of the carrier member 3 can be further reduced.

As shown in Fig. 1, the insert 4 is periodically formed on the outer peripheral portion by a concave portion 6a and a convex portion 6b which are engageable with the concave-convex portion 5 formed on the inner periphery of the support hole 2 of the carrier member 3. The formation of things. The material of the insert 4 can be, for example, a hard resin.

The carrier 1 for a double-side polishing apparatus of the present invention is such that the uneven portion 5 formed on the inner periphery of the support hole 2 of the carrier member 3 and the uneven portion 6 formed on the outer peripheral portion of the insert 4 are fitted.

In the carrier 1 for a double-side polishing apparatus of the present invention, the distortion of the peripheral portion (fitting portion) of the support hole of the carrier member 3 is reduced, and if the carrier 1 for such a double-side polishing device is used, the wafer is double-sidedly ground. By the effect of reducing the distortion around the support hole, the obtained flatness of the edge is improved, and the wafer having the unevenness of the flatness is reduced. [Examples]

Hereinafter, the present invention will be described in detail by showing examples and comparative examples, but the present invention is not limited thereto.

(Comparative Example 1) As a carrier for the double-side polishing apparatus, the shape of the slit portion of the concave portion 50a of the uneven portion formed on the inner circumference of the support hole of the carrier member 30 is a trapezoidal shape, and the distance d between the centers of the adjacent concave portions 50a is 9.6. The carrier member 30 of mm is fitted into the insert 40 to produce a carrier 10 for a double-side polishing apparatus as shown in FIG.

(Example 1) As a carrier for a double-side polishing apparatus, the shape of the notch portion of the concave portion 5a of the uneven portion 5 formed on the inner circumference of the support hole of the carrier member 3 is a table shape, and the distance d between the centers of the adjacent concave portions 5a is 19.1 mm, the carrier member 3 having a larger area of the convex portion 5b in the uneven portion 5 in the planar direction than the slit portion of the concave portion 5a is fitted to the insert 4 to produce a double-side polishing apparatus as shown in FIG. Carrier 1. d (19.1 mm) of Example 1 was about twice as large as d (9.6 mm) of Comparative Example 1.

In the carrier for the double-side polishing apparatus of the first embodiment and the comparative example 1, the distortion in the range shown in FIG. 5 (the periphery of the support hole of the carrier member) was confirmed by a three-dimensional measuring machine (manufactured by Tokyo Seimitsu Co., Ltd.). The measurement results are shown in Fig. 6(A). The average value of the amount of distortion was 24.2 μm in Example 1, and 29.1 μm in Comparative Example 1. It was confirmed that the distortion around the support hole was significantly reduced as compared with the comparative example. Further, these results are almost identical to the simulation results shown in Fig. 4(A).

Further, using these carriers, a 300 mm-diameter silicon wafer was subjected to double side polishing (DSP) processing to measure flatness (LSW-3000, manufactured by Kobe Steel Co., Ltd.). The result of the relative value of ESFQRrange when the comparison example 1 is used is shown in FIG. 6(B), and the result of the relative value of ESFQRmax is shown in FIG. 6(C). In Example 1, it was confirmed that the range width of the ESFQR was smaller than that of Comparative Example 1, and the variation of the edge flatness was reduced. At the same time, the value of ESFQRmax can be improved.

(Comparative Examples 2 to 4) When the carrier for the double-side polishing apparatus of Comparative Example 1 is used as a reference, the carrier for the double-side polishing apparatus having different amounts of twist around the support hole of the carrier member (Comparative Examples 2 to 4) The relationship between the amount of twist (magnification) around the support hole and the amount of deterioration of the flatness (nm) is shown in Table 1 and FIG. As a result, it was confirmed that the smaller the amount of distortion, the better the flatness.

【Table 1】

(Comparative Example 5) As in the case of the double-side polishing apparatus, the shape of the slit portion of the concave portion 50a of the concave-convex portion formed on the inner circumference of the support hole of the carrier member 30 is a table shape, and the adjacent concave portion 50a is formed. The carrier member 30 having a center distance d of 62 mm is fitted to the insert 40 to manufacture the carrier 10 for a double-side polishing apparatus as shown in FIG.

Using the manufactured carrier, DSP processing was performed on a silicon wafer having a diameter of 300 mm, but the insert 40 was detached from the carrier while the DSP was not processed.

As described above, if the distance d between the centers of the adjacent concave portions formed on the inner circumference of the support hole of the carrier member is less than 10 mm, the amount of twist around the support hole is greatly increased (Comparative Example 1), and if d is more than 60 mm, The insert was peeled off during wafer processing (Comparative Example 5). On the other hand, the carrier having a d of 10 mm or more and 60 mm or less has less distortion in the peripheral portion (fitting portion) of the support member (Example 1). When d is 60 mm, the insert does not fall off even if the wafer is processed by the DSP.

Further, the present invention is not limited by the foregoing embodiments. The above-described embodiments are exemplified, and have substantially the same configuration as the technical idea described in the patent application scope of the present invention, and the same effects are achieved in the technical scope of the present invention.

1, 10‧‧‧ Carrier for grinding device

2‧‧‧Support hole

3, 30‧‧‧ carrier mother

4, 40‧‧‧ inserts

5, 6‧‧‧

5a, 6a, 50a‧‧‧ recess

5b, 6b‧‧‧ convex

D‧‧‧distance

Fig. 1 is a schematic view showing an example of a carrier for a double-side polishing apparatus of the present invention. Fig. 2 is a schematic view showing an example of a carrier for a conventional double-side polishing apparatus. Fig. 3 is an explanatory view for explaining distortion generated in a carrier for a conventional double-side polishing apparatus. Fig. 4 is a graph showing the relationship between the deformation ratio of the periphery of the support hole of the carrier member and the distance d between the centers of the adjacent concave portions in the uneven portion of the carrier member. Fig. 5 is an explanatory view for explaining a portion in which the distortion is measured in Example 1 and Comparative Example 1. Fig. 6 is a graph showing the amount of twist around the support hole measured in Example 1 and Comparative Example 1 (Fig. 6(A)), relative value of ESFQRrange (Fig. 6(B)), and relative value of ESFQRmax (Fig. 6(C) The measurement result. Fig. 7 is a view showing the relationship between the distortion and the flatness (nm) of the periphery of the support hole of the carrier member in Comparative Examples 2 to 4.

Claims (3)

A carrier for a double-side polishing apparatus is disposed in a double-side polishing apparatus for polishing a wafer on both sides, and includes a carrier member formed with a support hole for supporting the wafer during polishing, and along the carrier An insert that is disposed on the inner circumference of the support hole and is formed with an inner peripheral portion that is in contact with the outer peripheral portion of the wafer, wherein the carrier member is periodically formed with a concavo-convex portion along an inner circumference of the support hole, The distance between the centers of the adjacent concave portions in the uneven portion is 10 mm or more and 60 mm or less, and the area of the convex portion in the uneven portion is larger than the area of the cut portion of the concave portion in the planar direction of the carrier member, and the insert is on the outer circumference. a concave-convex portion is periodically formed to be fitted to the concave-convex portion formed on an inner circumference of the support hole, and the concave-convex portion of the carrier member formed on an inner circumference of the support hole and the insert are formed on The uneven portion of the outer peripheral portion is fitted. The carrier for a double-side polishing apparatus according to claim 1, wherein a shape of the cutout portion of the recess formed in the inner circumference of the support hole of the carrier member is a triangle, a rectangle, a trapezoid, a wedge, a keyhole, and a U Any of a shape and a circle. The carrier for a double-side polishing apparatus according to claim 1 or 2, wherein the carrier member is formed in the uneven portion of the inner circumference of the support hole, and the area of the convex portion in the planar direction of the carrier member It is 4 times or more of the area of the slit portion of the concave portion.