CN116000784A

CN116000784A - Bearing piece of silicon wafer double-sided polishing device and silicon wafer double-sided polishing device

Info

Publication number: CN116000784A
Application number: CN202211718374.8A
Authority: CN
Inventors: 贺云鹏; 王贺
Original assignee: Xian Eswin Material Technology Co Ltd
Current assignee: Xian Eswin Material Technology Co Ltd
Priority date: 2022-12-29
Filing date: 2022-12-29
Publication date: 2023-04-25
Also published as: TW202327798A

Abstract

The embodiment of the invention discloses a bearing piece of a silicon wafer double-sided polishing device and the silicon wafer double-sided polishing device, wherein the bearing piece comprises: a body formed with a through hole; an annular liner lined in the through hole of the body, the liner being for accommodating a silicon wafer, wherein the liner has a porous hydrophobic structure such that polishing liquid accumulated in a gap between an outer peripheral surface of the silicon wafer and an inner peripheral surface of the liner can be evacuated through pores in the porous hydrophobic structure. According to the bearing piece provided by the embodiment of the invention, the quantity of the polishing solution at the periphery of the silicon wafer can be reduced, the non-uniformity of the polishing degree is improved, and the surface flatness of the silicon wafer is improved.

Description

Bearing piece of silicon wafer double-sided polishing device and silicon wafer double-sided polishing device

Technical Field

The invention relates to the field of semiconductor silicon wafer production, in particular to a bearing piece of a silicon wafer double-sided polishing device and the silicon wafer double-sided polishing device.

Background

In the production process of semiconductor silicon wafers, it is generally required to perform double-sided polishing on the wafers to remove damages generated on the surfaces of the wafers during the wafer molding process and to form the surfaces of the wafers into mirror surfaces, which is usually performed by using a double-sided polishing apparatus for wafers.

In a double-sided silicon wafer polishing apparatus, a silicon wafer is carried in a carrier. Specifically, the carrier may be disposed between the upper and lower polishing pads and may be formed with a receiving portion penetrating the carrier, in which the silicon wafer may be received to move with the carrier relative to the upper and lower polishing pads, thereby achieving polishing of both circular main surfaces of the silicon wafer by the upper and lower polishing pads.

In the above polishing process, the polishing liquid from the polishing pad is concentrated in the gap between the outer peripheral surface of the silicon wafer and the inner peripheral wall of the accommodating portion, so that the amount of the polishing liquid at the peripheral edge of the silicon wafer is increased, resulting in an increase in the degree of polishing of the portion of the two circular main surfaces of the silicon wafer near the peripheral edge of the silicon wafer, thereby resulting in deterioration in the surface flatness of the silicon wafer.

With the continuous development of semiconductor technology, the requirement on the surface flatness of a silicon wafer is higher and higher, and the conventional silicon wafer double-sided polishing device cannot meet the requirement due to the existence of the problems.

Disclosure of Invention

In order to solve the above technical problems, it is desirable to provide a carrier of a double-sided silicon wafer polishing device and a double-sided silicon wafer polishing device, which can reduce the polishing degree at the periphery of a silicon wafer, thereby reducing the difference between the polishing degree at the periphery and the polishing degree at the center of the silicon wafer and improving the surface flatness of the silicon wafer.

The technical scheme of the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a carrier of a dual-sided polishing apparatus for a silicon wafer, the carrier including:

a body formed with a through hole;

an annular liner lined in the through hole of the body, the liner being for accommodating a silicon wafer, wherein the liner has a porous hydrophobic structure such that polishing liquid accumulated in a gap between an outer peripheral surface of the silicon wafer and an inner peripheral surface of the liner can be evacuated through pores in the porous hydrophobic structure.

In a second aspect, an embodiment of the present invention provides a dual-sided silicon wafer polishing apparatus, including the carrier according to the first aspect.

The embodiment of the invention provides a bearing piece of a silicon wafer double-sided polishing device and the silicon wafer double-sided polishing device, and because the lining is of a porous hydrophobic structure, polishing liquid gathered in the gap can be gradually dispersed through pores in the hydrophobic structure, so that a small amount of polishing liquid is always kept at the gap, the polishing degree of the periphery of the silicon wafer is reduced, and the surface flatness of the silicon wafer is improved.

Drawings

FIG. 1 is a schematic top view of a carrier of a double-sided silicon wafer polishing apparatus according to an embodiment of the present invention;

FIG. 2 isbase:Sub>A schematic view in partial cross-section taken along line A-A in FIG. 1;

FIG. 3 is a schematic partial cross-sectional view of a carrier according to a preferred embodiment of the invention;

FIG. 4 is a schematic top view of a double-sided silicon wafer polishing apparatus according to an embodiment of the present invention;

fig. 5 is a front view schematically showing a silicon wafer double-sided polishing apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1 and 2 in combination with fig. 4 and 5, an embodiment of the present invention provides a carrier 10 of a silicon wafer double-sided polishing apparatus 1, where the carrier 10 may include:

a body 11 formed with a through hole 11H;

an annular inner liner 12 lined in the through hole 11H of the body 11, the inner liner 12 for accommodating a silicon wafer W, wherein the inner liner 12 has a porous hydrophobic structure 121 as shown in fig. 2, so that a polishing liquid PL gathered in a gap G between an outer circumferential surface WS of the silicon wafer W and an inner circumferential surface 12S of the inner liner 12 can be evacuated via the pores P in the porous hydrophobic structure 121 as schematically shown by curved arrows in fig. 2, such as evacuated to a lower polishing pad 50 to be described in further detail below.

With the carrier 10 according to the embodiment of the present invention, since the inner liner 12 has the porous hydrophobic structure 121, the polishing liquid PL accumulated in the above-described gap G can be gradually evacuated through the pores P in the hydrophobic structure 121 so that a small amount of the polishing liquid PL is always maintained at the gap G, thereby reducing the polishing degree at the periphery of the silicon wafer W and improving the surface flatness of the silicon wafer.

To facilitate the production and manufacture of the liner 12 described above, in a preferred embodiment of the present invention, referring to FIG. 3, the liner 12 may be made of a porous material. In this way, it is no longer necessary to provide the porous and hydrophobic structure 121 exclusively in the liner 12, but the whole of the liner 12 is of a porous material, thereby enabling the production and manufacturing process of the liner 12 to be simplified.

With respect to the porosity of the above porous material, if the porosity is too large, the dispersion of the polishing liquid PL in the above gap G is caused too fast, so that there is insufficient polishing liquid PL at the peripheral edge of the silicon wafer W, whereas if the porosity is too small, the polishing liquid PL in the above gap G is not sufficiently dispersed, whereby there is still a problem that the amount of polishing liquid PL at the peripheral edge of the silicon wafer W is large and the polishing degree is high. In this regard, in a preferred embodiment of the present invention, the porosity of the porous material may be between 40% and 60%, so that it is possible to ensure that an appropriate amount of the polishing liquid PL is present at the peripheral edge of the silicon wafer W, thereby ensuring the degree of polishing and the surface flatness.

Preferably, the porous material may be a porous ceramic. The porous ceramic has the advantages of high strength, stable physical and chemical properties and the like, is suitable for being used in the process of double-sided polishing of the silicon wafer W, and is easy to produce and manufacture.

Preferably, the porous ceramic material may be a pure carbon material with water resistance and acid and alkali resistance.

In order to make the double-sided silicon wafer polishing apparatus 1 to which the carrier 10 is mounted more compact in structure and to ensure polishing quality, in a preferred embodiment of the present invention, referring to fig. 1, the body 11 may be formed with three through holes 11H, and the three through holes 11H may be uniformly distributed in the body 11.

Referring to fig. 4, an embodiment of the present invention also provides a double-sided silicon wafer polishing apparatus 1, and the double-sided silicon wafer polishing apparatus 1 may include the carrier 10 according to the above embodiments of the present invention.

Referring to fig. 4, the body 11 may have a disk shape and have body external teeth 11T, as schematically shown by thick solid lines in fig. 4, and the silicon wafer double-sided polishing apparatus 1 may further include:

an inner ring gear 20, the inner ring gear 20 having inner ring gear outer teeth 20T, as also schematically shown by thick solid lines in fig. 4;

an outer ring gear 30 provided on the outer periphery of the ring gear 20, the outer ring gear 30 having an outer ring gear inner tooth 30T, as also schematically shown by a thick solid line in fig. 4;

wherein the body external teeth 11T are used for meshing with the ring gear external teeth 20T and the external ring gear internal teeth 30T, so that when the ring gear 20 and the external ring gear 30 rotate respectively, the carrier 10 and the silicon wafer W carried in the carrier 10 can be driven to move.

Referring to fig. 5, the silicon wafer double-sided polishing apparatus 1 may further include upper and

lower polishing pads

40 and 50 disposed above and below the carrier 10, respectively, to sandwich the carrier 10.

Referring to fig. 5, the silicon wafer double-sided polishing apparatus 1 may further include an upper platen 60 disposed above the upper polishing pad 40 and a lower platen 70 disposed below the lower polishing pad 50, the upper platen 60 and the lower platen 70 being configured to provide a clamping force for clamping the upper polishing pad 40 and the lower polishing pad 50 to the carrier 10.

It should be noted that: the technical schemes described in the embodiments of the present invention may be arbitrarily combined without any collision.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A carrier for a double-sided silicon wafer polishing apparatus, the carrier comprising:

a body formed with a through hole;

2. The carrier of claim 1, wherein the liner is made of a porous material.

3. The carrier of claim 2, wherein the porous material has a porosity of between 40% and 60%.

4. A carrier according to claim 2 or 3, wherein the porous material is a porous ceramic.

5. The carrier of claim 4, wherein the porous ceramic is a water-resistant, acid-base-resistant pure carbon material.

6. The carrier according to claim 1 or 2, characterized in that the body is formed with three through holes, which are evenly distributed in the body.

7. A double-sided silicon wafer polishing apparatus, characterized in that the double-sided silicon wafer polishing apparatus comprises the carrier according to any one of claims 1 to 6.

8. The double-sided silicon wafer polishing apparatus as set forth in claim 7, wherein the body is disk-shaped and has external teeth of the body, and further comprising:

an inner gear ring having inner gear ring outer teeth;

an outer ring gear provided at the outer periphery of the inner ring gear, the outer ring gear having outer ring gear inner teeth;

wherein the body external teeth are used for meshing with the ring gear external teeth and the external ring gear internal teeth.

9. The double-sided silicon wafer polishing apparatus as set forth in claim 8, further comprising upper and lower polishing pads disposed above and below the carrier, respectively, to clamp the carrier.

10. The double-sided silicon wafer polishing apparatus as set forth in claim 9, further comprising an upper platen disposed above the upper polishing pad and a lower platen disposed below the lower polishing pad, the upper platen and the lower platen being adapted to provide a clamping force that clamps the upper polishing pad and the lower polishing pad to the carrier.