US20080003935A1

US20080003935A1 - Polishing pad having surface texture

Info

Publication number: US20080003935A1
Application number: US11/478,605
Authority: US
Inventors: Chung-Chih Feng; I-Peng Yao; Chen-Hsiang Chao; Kun-Cheng Sung
Original assignee: San Fang Chemical Industry Co Ltd
Current assignee: San Fang Chemical Industry Co Ltd
Priority date: 2006-07-03
Filing date: 2006-07-03
Publication date: 2008-01-03

Abstract

The present invention relates to a polishing pad having a surface texture. The surface texture is disposed on the polishing surface of the polishing pad. The surface texture comprises at least one first groove, at least one second groove, and a plurality of holes. The second groove extends from a central portion of the polishing pad to the edge of the polishing pad, and the first groove(s) is intersected with the second groove(s) to form a plurality of intersection points. The holes are disposed at the intersection points, and the depth of the holes is larger than that of the first groove. Thus, the second groove(s) enables impurities suspended in the polishing slurry to be quickly removed from the polishing pad, and the holes can store the polishing slurry to delay the polishing particles in the polishing slurry from departing from the polishing pad.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a polishing pad having a surface texture, and more particularly, to a polishing pad with holes to store polishing slurry.
2. Description of the Related Art
Polishing generally refers to a wear control for a preliminary coarse surface in the process of chemical mechanical polishing (CMP), which makes the slurry containing fine particles evenly dispersed on the upper surface of a polishing pad, and at the same time places a polishing workpiece against the polishing pad and then rubs the workpiece repeatedly with a regular motion. The polishing workpiece may be objects such as a semiconductor, a storage medium substrate, an integrated circuit, an LCD flat-panel glass, an optical glass and a photoelectric panel. In order to maintain the distribution and flow of the polishing slurry and the planarization and polishing efficiency after the chemical mechanical polishing, the upper surface of the polishing pad is usually cut with a plurality of grooves or formed with a surface texture. Therefore, the polishing effect of the polishing pad on the workpiece to be polished is easily affected by the grooves and the surface texture.
Referring to FIG. 1, a top view of a polishing pad having a surface texture disclosed in the ROC (Taiwan) Patent Publication No. 504,429 is shown. The surface texture of the polishing pad 1 comprises a plurality of concentric circular grooves 11, wherein the depth and the width of the circular grooves 11 are designed in accordance with the requirement. However, the polishing pad 1 has the disadvantage that the impurities produced during the polishing process cannot be quickly removed from the polishing pad 1, thus negatively affecting the polishing precision and the service life of the polishing pad 1.
Referring to FIG. 2, a top view of a polishing pad having a surface texture disclosed in the ROC (Taiwan) Patent Publication No. 562,716 is shown. The surface texture of the polishing pad 2 comprises a plurality of radial grooves 21, wherein the radial grooves 21 are connected to the center 22 of the polishing pad 2 and the edge 23 of the polishing pad 2. The advantage of the polishing pad 2 is that the impurities produced during the polishing process can be quickly removed from the polishing pad 2. However, the polishing pad 2 has the disadvantage that the polishing particles in the polishing slurry are also quickly removed from the polishing pad 2, thus negatively affecting the polishing precision and the service life of the polishing pad 2.
Consequently, there is an existing need for a polishing pad having a surface texture to solve the above-mentioned problems.

SUMMARY OF THE INVENTION

The objective of the present invention is to provide a polishing pad having a surface texture. The polishing pad comprises a surface texture disposed on a polishing surface of the polishing pad. The surface texture comprises at least one first groove, at least one second groove, and a plurality of holes. The second groove is connected to the edge of the polishing pad, and the first groove(s) is intersected with the second groove(s) to form a plurality of intersection points. The holes are disposed at the intersection points, and the depth of the holes is larger than that of the first groove.
Thus, the second groove(s) enables the impurities suspended in the polishing slurry to be quickly removed, and the holes then store the polishing slurry to delay the polishing particles in the polishing slurry from departing from the polishing pad.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a polishing pad having a surface texture disclosed in the ROC (Taiwan) Patent Publication No. 504,429;

FIG. 2 is a top view of a polishing pad having a surface texture disclosed in the ROC (Taiwan) Patent Publication No. 562,716;

FIG. 3 is a top view of the polishing pad according to the first embodiment of the present invention;

FIG. 4 is a top view of the polishing pad according to the second embodiment of the present invention;

FIG. 5 is a top view of the polishing pad according to the third embodiment of the present invention;

FIG. 6 is a top view of the polishing pad according to the fourth embodiment of the present invention;

FIG. 7 is a top view of the polishing pad according to the fifth embodiment of the present invention; and

FIG. 8 is a top view of the polishing pad according to the sixth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a polishing pad having a surface texture. The polishing pad is suitable for polishing an object to be polished in the chemical mechanical polishing (CMP) process. The object to be polished comprises, but is not limited to, objects such as semiconductors, storage medium substrates, integrated circuits, LCD flat glass, optical glass, and photoelectric panels.
According to the present invention, the polishing pad comprises a surface texture disposed on a polishing surface of the polishing pad. The surface texture comprises at least one first groove, at least one second groove, and a plurality of holes. That is, the first groove, the second groove and the holes are on the same surface (polishing surface).In a preferred embodiment, the first grooves are a plurality of circular grooves with different radii from the top view and the circular grooves are concentric grooves. However, the first grooves can also be a plurality of rectangular grooves with different side lengths and the rectangular grooves are concentric grooves. Alternatively, the first groove(s) may be a spiral groove, or grooves of other shapes.
The second groove(s) extends from a central portion of the polishing pad to an edge of the polishing pad, and the first groove(s) is intersected with the second groove(s) to form a plurality of intersection points. Preferably, the second groove(s) is a plurality of radial grooves from the top view, each of which is a linear or arced groove. The holes are disposed at the intersection points. The holes are blind holes and the depth of the holes is larger than that of the first groove(s) and the second groove(s). Thus, the second groove enables the impurities suspended in the polishing slurry to be quickly removed, and the holes then store the polishing slurry to delay the polishing particles in the polishing slurry from departing from the polishing pad.
The present invention will be described in detail with the following examples, but it does not mean that the present invention is limited to the content disclosed by the examples.

EXAMPLE 1

Referring to FIG. 3, a top view of the polishing pad according to the first embodiment of the present invention is shown. The surface texture of the polishing pad 3 of the present embodiment comprises a plurality of the first grooves 31, a plurality of the second grooves 32, and a plurality of holes 33. The first grooves 31 are a plurality of concentric circular grooves, and the first grooves are a plurality of circular grooves with different radii from the top view. The second grooves 32 are a plurality of radial grooves, and each of the second grooves 32 is a linear groove extending from a central portion of the polishing pad 3 to the edge 34 of the polishing pad 3. The first grooves 31 are intersected with the second grooves 32 to form a plurality of intersection points. The holes 33 are disposed at the intersection points, and the depth of the holes 33 is larger than that of the first grooves 31 and the second grooves 32. The diameter of the hole 33 is larger than the width of the first grooves 31 and the second grooves 32.

EXAMPLE 2

Referring to FIG. 4, a top view of the polishing pad according to the second embodiment of the present invention is shown. The surface texture of the polishing pad 4 of the present embodiment comprises a plurality of the first grooves 41, a plurality of the second grooves 42, and a plurality of holes 43. The first grooves 41 are a plurality of concentric circular grooves. The second grooves 42 are a plurality of radial grooves, and each of the second grooves 42 is a linear groove extending from a central portion of the polishing pad 4 to the edge 44 of the polishing pad 4. The first grooves 41 are intersected with the second grooves 42 to form a plurality of intersection points. The holes 43 are disposed at the intersection points, and the depth of the holes 43 is larger than that of the first grooves 41 and the second grooves 42. The diameter of the hole 43 is larger than the width of the first grooves 41 and the second grooves 42. The difference between the surface texture of the polishing pad 4 of the present embodiment and that of the polishing pad 3 of the first embodiment is that the first groove 411 at the innermost circle of the polishing pad 4 are not intersected with the second grooves 42.

EXAMPLE 3

Referring to FIG. 5, a top view of the polishing pad according to the third embodiment of the present invention is shown. The surface texture of the polishing pad 5 of the present embodiment comprises a plurality of the first grooves 51, a plurality of the second grooves 52, a plurality of the first holes 53, and a plurality of the second holes 55. The first grooves 51 are a plurality of concentric circular grooves. The second grooves 52 are a plurality of radial grooves, and each of the second grooves 52 is a linear groove extending from a central portion of the polishing pad 5 to the edge 54 of the polishing pad 5. The first grooves 51 are intersected with the second grooves 52 to form a plurality of intersection points. The first holes 53 are disposed at the intersection points, and the depth of the first holes 53 is larger than that of the first grooves 51 and the second grooves 52. The second holes 55 are disposed on the second grooves 52 except for the intersection points, and the depth of the second holes 55 is the same as that of the first holes 53. The diameters of the first hole 53 and the second holes 55 are larger than the widths of the first grooves 51 and the second grooves 52.

EXAMPLE 4

Referring to FIG. 6, a top view of the polishing pad according to the fourth embodiment of the present invention is shown. The surface texture of the polishing pad 6 of the present embodiment comprises a plurality of the first grooves 61, a plurality of the second grooves 62, and a plurality of holes 63. The first grooves 61 are a plurality of concentric rectangular grooves from the top view, and the first grooves 61 are a plurality of rectangular grooves with different side lengths. The second grooves 62 are a plurality of radial grooves, and each of the second grooves 62 is a linear groove extending from a central portion of the polishing pad 6 to the edge 64 of the polishing pad 6. The first grooves 61 are intersected with the second grooves 62 to form a plurality of intersection points. The holes 63 are disposed at the intersection points, and the depth of the holes 63 is larger than that of the first grooves 61 and the second grooves 62.

EXAMPLE 5

Referring to FIG. 7, a top view of the polishing pad according to the fifth embodiment of the present invention is shown. The surface texture of the polishing pad 7 of the present embodiment comprises a first groove 71, a plurality of the second grooves 72, and a plurality of holes 73. The first groove 71 is a spiral groove from the top view. The second grooves 72 are a plurality of radial grooves, and each of the second grooves 72 is a linear groove extending from a central portion of the polishing pad 7 to the edge 74 of the polishing pad 7. The first groove 71 is intersected with the second grooves 72 to form a plurality of intersection points. The holes 73 are disposed at the intersection points, and the depth of the holes 73 is larger than that of the first groove 71 and the second grooves 72. The diameter of the hole 73 is larger than the widths of the first grooves 71 and the second grooves 72.

EXAMPLE 6

Referring to FIG. 8, a top view of the polishing pad according to the sixth embodiment of the present invention is shown. The surface texture of the polishing pad 8 of the present embodiment comprises a plurality of the first grooves 81, a plurality of the second grooves 82, and a plurality of holes 83. The first grooves 81 are a plurality of concentric circular grooves. The second grooves 82 are a plurality of radial grooves, and each of the second grooves 82 is an arced groove extending from a central portion of the polishing pad 8 to the edge 84 of the polishing pad 8. The first grooves 81 are intersected with the second grooves 82 to form a plurality of intersection points. The holes 83 are disposed at the intersection points and the depth of the holes 83 is larger than that of the first grooves 81 and the second grooves 82. The diameter of the hole 83 is larger than the widths of the first grooves 81 and the second grooves 82.
While several embodiments of the present invention have been illustrated and described, various modifications and improvements can be made by those skilled in the art. The embodiments of the present invention are therefore described in an illustrative but not restrictive sense. It is intended that the present invention may not be limited to the particular forms as illustrated, and that all modifications which maintain the spirit and scope of the present invention are within the scope as defined in the appended claims.

Claims

1. A polishing pad comprising:

a textured polishing surface;

at least one first groove exposed at and formed in the textured polishing surface;

at least one second groove exposed at and formed in the textured polishing surface, the at least one second groove extending from a central portion of the polishing surface to an edge of the polishing surface, wherein the at least one first groove intersects with the at least one second groove to form a plurality of intersection points; and

a plurality of holes exposed at and formed in the textured polishing surface, the plurality of holes disposed at the intersection points, wherein the depth of the holes is larger than that of the at least one first groove.

2. The polishing pad as claimed in claim 1, wherein the at least one first groove comprises a plurality of concentric circular grooves surrounding a center of the textured polishing surface.

3. The polishing pad as claimed in claim 1, wherein the at least one first groove comprises a plurality of concentric rectangular grooves surrounding a center of the textured polishing surface.

4. The polishing pad as claimed in claim 1, wherein the at least one first groove is a spiral groove.

5. The polishing pad as claimed in claim 1, wherein the at least one second groove comprises a plurality of radial grooves.

6. The polishing pad as claimed in claim 5, wherein each of the radial grooves is a linear groove.

7. The polishing pad as claimed in claim 5, wherein each of the radial grooves is an arced groove.

8. A polishing pad comprising:

a textured polishing surface;

a plurality of concentric circular grooves exposed at and located in the textured polishing surface;

a plurality of radial grooves exposed at and located in the textured polishing surface, the plurality of radial groove extending from a central portion of the polishing surface to an edge of the polishing surface, wherein the circular grooves intersect with the radial grooves to form a plurality of intersection points; and

a plurality of the first holes exposed at and located in the textured polishing surface, wherein the plurality of first holes are disposed at the intersection points, and wherein the depth of the holes is larger than that of the circular grooves.

9. The polishing pad as claimed in claim 8, wherein each of the radial grooves is a linear groove.

10. The polishing pad as claimed in claim 8, wherein each of the radial grooves is an arced groove.

11. The polishing pad as claimed in claim 8, further comprising a plurality of the second holes disposed on the circular grooves and spaced from the intersection points.

12. The polishing pad as claimed in claim 1, wherein the holes are blind holes.

13. The polishing pad as claimed in claim 1, wherein a diameter of the holes is larger than a width of the at least one first groove and a width of the at least one second groove.

14. The polishing pad as claimed in claim 8, wherein a diameter of the first holes is larger than a width of the circular grooves and a width of the radials grooves.

15. The polishing pad as claimed in claim 11, wherein a diameter of the second holes is larger than a width of the circular grooves.