Endpoint detection window, chemical mechanical polishing pad with window and preparation method thereof

Abstract

The present invention relates to B24B, and more specifically, the present invention relates to an endpoint detection window, a chemical mechanical polishing pad with a window and a preparation method thereof. A side surface of the window is provided with a plurality of circumferential grooves. In the present invention, a column-shaped window with a specially designed side surface structure is provided and subjected to integrated pouring and molding with a polishing pad to manufacture a chemical mechanical polishing pad having high bonding strength between the window and the polishing pad. As a side surface of the window is of a multi-groove structure, not only is the bonding contact area between the window and the pad increased, but also a convex structure is formed by a polishing pad body material poured into the grooves so as to form an embedded bonding manner with a groove structure of a window material.

Claims

1. An endpoint detection window, wherein a side surface of the window is provided with a plurality of circumferential grooves, and the maximum circumferential depression depth (R) of the grooves is 0.5-3 mm.

2. The endpoint detection window of claim 1, wherein the maximum radial width (L) of the grooves is equal to or greater than R.

3. The endpoint detection window of claim 1, wherein the depression area of the grooves is equal to or less than 2R.sup.2.

4. The endpoint detection window of claim 1, wherein the maximum radial width (L) of the grooves is equal to or less than 5R.

5. The endpoint detection window of claim 1, wherein the shape of the grooves is selected from one or more of an arc, a polygon and a wave shape; and the polygon is selected from one or more of a triangle, a rectangle and a zigzag.

6. The endpoint detection window of claim 1, wherein the distance (H) of adjacent edges of the adjacent grooves is 0-5R.

7. The endpoint detection window of claim 1, wherein the roughness of an exposed surface of the window is 0.1-10 Ra.

8. The endpoint detection window of claim 1, wherein the shape of the exposed surface of the window is selected from one or more of a circle, an ellipse and a rounded rectangle.

9. A chemical mechanical polishing pad with a window, wherein the chemical mechanical polishing pad is provided with the endpoint detection window of claim 1.

10. A preparation method of the chemical mechanical polishing pad with a window of claim 9, wherein the chemical mechanical polishing pad is prepared by integrated pouring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a schematic diagram of a cross section of a traditional polishing pad;

[0025] FIG. 2 is a schematic diagram of a cross section of a window provided in Example 1;

[0026] FIG. 3 is a schematic diagram of a front view of the window provided in Example 1;

[0027] FIG. 4 is a schematic diagram showing bonding of a polishing pad and a window in Example 2;

[0028] FIG. 5 is a schematic diagram showing an enlarged local structure of the window in Example 2;

[0029] FIG. 6 is a schematic diagram showing bonding of a polishing pad and a window in Example 3;

[0030] FIG. 7 is a schematic diagram showing bonding of a polishing pad and a window in Example 4; and in the figures, 1 refers to a groove, and 2 refers to an exposed surface.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Examples

Example 1

[0031] As shown in FIG. 2 to FIG. 3, this example provides a window. A side surface of the window is provided with a plurality of circumferential grooves 1, the maximum circumferential depression depth (R) of the grooves 1 is 0.5 mm, the maximum radial width (L) of the grooves 1 is 0.5 mm, and the depression area of the grooves 1 is 0.25 mm.sup.2. The shape of the grooves 1 is selected from a rectangle, the distance (H) of adjacent edges of the adjacent grooves 1 is 0.5 mm, and the roughness of an exposed surface 2 of the window is 1 Ra. The shape of the exposed surface 2 is a rounded rectangle, the diameter of a long side is 60 mm, and the diameter of a short side is 15 mm.

Example 2

[0032] As shown in FIG. 4 to FIG. 5, this example provides a window. A side surface of the window is provided with a plurality of circumferential grooves 1, the maximum circumferential depression depth (R) of the grooves 1 is 3 mm, the maximum radial width (L) of the grooves 1 is 3 mm, and the depression area of the grooves 1 is 9 mm.sup.2. The shape of the grooves 1 is a rectangle, the distance (H) of adjacent edges of the adjacent grooves 1 is 3 mm, and the roughness of an exposed surface 2 of the window is 5 Ra. The shape of the exposed surface 2 is a rounded rectangle, the diameter of a long side is 80 mm, and the diameter of a short side is 25 mm.

Example 3

[0033] As shown in FIG. 6, this example provides a window. A side surface of the window is provided with a plurality of circumferential grooves 1, the maximum circumferential depression depth (R) of the grooves 1 is 1 mm, the maximum radial width (L) of the grooves 1 is 1 mm, and the depression area of the grooves 1 is 0.43 mm.sup.2. The shape of the grooves 1 is a semicircle, the distance (H) of adjacent edges of the adjacent grooves 1 is 0 mm, and the roughness of an exposed surface 2 of the window is 4 Ra. The shape of the exposed surface 2 is a rounded rectangle, the diameter of a long side is 70 mm, and the diameter of a short side is 20 mm.

Example 4

[0034] As shown in FIG. 7, this example provides a window. A side surface of the window is provided with a plurality of circumferential grooves 1, the maximum circumferential depression depth (R) of the grooves 1 is 1 mm, the maximum radial width (L) of the grooves 1 is 1 mm, and the depression area of the grooves 1 is 0.5 mm.sup.2. The shape of the grooves 1 is a triangle, the angle of the hypotenuse and circumference of the triangle is 45, the distance (H) of adjacent edges of the adjacent grooves 1 is 0 mm, and the roughness of an exposed surface 2 of the window is 4 Ra. The shape of the exposed surface 2 is a rounded rectangle, the diameter of a long side is 70 mm, and the diameter of a short side is 20 mm.

Performance Evaluation

[0035] 1. Performance test of an endpoint detection window: Polishing research was carried out by using Anji A28 copper abrasive slurry on a single-module integrated CMP polishing machine of Hangzhou SIZONE Electronic Technology Inc. A 10 kA bare copper wafer was used as a test wafer (moniter wafer) to determine a polishing pad with an endpoint detection window. Unless otherwise specified, polishing conditions used in all polishing experiments are as follows: a polishing platform at a rotation speed of 93 rpm; a polishing head at a rotation speed of 87 rpm; and a polishing solution at a flow rate of 170 mL/min. According to the endpoint detection window, the polishing time was controlled to 40-60 s/wafer. More than 100 wafers were polished in the experiment. After the polishing pad was used, the polishing pad was taken down to check the window position of the polishing pad. It can be confirmed that the window with a grooved edge is not prone to the phenomena of falling and leakage during polishing.

[0036] The bonding situation of a window and a polishing pad is judged through evaluation of the bonding strength between the window and the polishing pad.

[0037] Evaluation of the bonding strength: Two kinds of samples were used in the experiment, one is a traditional polishing pad with a smooth and flat endpoint detection window (control sample), and the other one is a polishing pad with a window as described in the present patent. Connected parts of the polishing pads and the windows were cut and prepared into test samples having a width of 1 cm and a length of 8 cm. Each sample involved the window at one end and the polishing pad at the other end. The two ends of each sample were clamped by a 200 kg sensor tensile machine to test the maximum load for separation of the window and the polishing pad of the sample.

TABLE-US-00001 TABLE 1 Sample Maximum load/pound force name First sample Second sample Third sample Control 22.38 10.61 21.25 sample Example 1 130.40 100.60 116.43 Example 2 99.73 102.31 97.65 Example 3 76.53 65.41 78.32 Example 4 97.34 94.39 93.87

[0038] According to test results in Table 1, it can be seen that the window provided by the present invention has better bonding strength with a polishing pad body, and meanwhile, the phenomenon of falling of the endpoint detection window of the polishing pad caused by a poor bonding force is avoided, thereby greatly improving the use effect of the polishing pad.