Polishing pad having a surface texture and method and apparatus for fabricating the same
The present invention relates to a polishing pad having a surface texture and a method for fabricating the same. The fabricating method comprises the following steps: (a) providing a substrate which has a surface for polishing an object to be polished; (b) providing a freely movable high-energy laser; and (c) forming a surface texture on the surface of the substrate by using the high-energy laser. Thereby, burrs and deformation of fabricated polishing pad may not occur, and when the polishing pad is used, the slurry can maintain good flowage without scraping the object to be polished. Moreover, the desired surface texture can be fabricated rapidly and correctly by using a high-energy laser with extremely high reproducibility.
1. Field of the Invention
The present invention relates to a polishing pad having a surface texture and a method and an apparatus for fabricating the same, and more particularly, to a polishing pad having a surface texture formed by using a movable high-energy laser and a method and an apparatus for fabricating the same.
2. Description of the Related Art
Polishing generally refers to regularly rubbing an object to be polished against the polishing pad to and fro, in which a slurry containing fine particles is evenly dispersed on the upper surface of a polishing pad, for abrasion control of an initially rough surface in a chemo-mechanical polishing (CMP) process. The object to be polished is, for example, a semiconductor, a storage medium substrate, an integrated circuit, an LCD plate glass, an optical glass, a photoelectric panel, or the like. In order to keep the distribution and flowage of the slurry and the planarization and efficiency of the CMP, usually a plurality of grooves are opened or a surface texture is formed on the top surface of the polishing pad. Therefore, the polishing effect of the polishing pad to the object to be polished is tendered to be affected by the grooves or the surface texture.
Referring to
Moreover, U.S. Pat. No. 5,489,233 discloses a polishing pad having a surface texture being fabricated by embossing, pressing, casting, cutting, photolithograph, or the like.
However, a polishing pad having a surface texture which is fabricated by cutting will have burrs and residues, thus scraping the surface of the semiconductor, storage medium substrate, integrated circuit, LCD plate glass, optical glass, or photoelectric panel. The surfaces of polishing pads having a surface texture which are fabricated by embossing, pressing, and casting are easily deformed by the influence of heat pressing, thus affecting the flowage of the slurry. Furthermore, in the embossing and screen printing process, one kind of surface texture needs a mold or screen, and other polishing pads with same groove width and groove depth cannot be fabricated stably.
Referring to
Consequently, there is an existing need for a polishing pad having a surface texture and a method and apparatus for fabricating the same to solve the above-mentioned problems.
SUMMARY OF THE INVENTIONThe objective of the present invention is to provide a method for fabricating a polishing pad having a surface texture, comprising the following steps:
(a) providing a substrate, which has a surface for polishing an object to be polished;
(b) providing a freely movable high-energy laser; and
(c) forming a surface texture on the surface of the substrate by using the high-energy laser.
Thereby, the fabricated polishing pad will not have burrs or be deformed, and when in use, the slurry can maintain good flowage without scraping the object to be polished. Moreover, a desired surface texture can be fabricated rapidly and correctly by a high-energy laser, with extremely high reproducibility.
In a preferred embodiment, the step (c) further comprises:
(c1) providing a processing pattern; and
(c2) forming a surface texture on the surface of the polishing pad by using the high-energy laser according to the processing pattern.
Thereby, different processing patterns can be designed to adjust the width and depth of the groove of the surface texture or form an inclined groove as desired.
Another objective of the present invention is to provide an apparatus for fabricating a polishing pad having a surface texture. The apparatus comprises a platform, a high-energy laser generating apparatus, and a reflecting apparatus. The platform is used to carry a substrate having a surface for polishing an object to be polished. The high-energy laser generating apparatus is used to generate a high-energy laser. The reflecting apparatus is used to reflect the high-energy laser to the surface of the substrate, such that a surface texture is formed on the surface of the substrate. Thereby, the surface texture can be rapidly formed on the surface by the high-energy laser through the fast rotation or movement of the reflecting apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention provides a polishing pad having a surface texture and a method for fabricating the same. The polishing pad is used to grind or polish an object to be polished in a chemo-mechanical polishing (CMP) process. The object to be polished comprises, but is not limited to, a semiconductor, storage medium substrate, integrated circuit, LCD plate glass, optical glass, photoelectric panel, or another object.
Referring to
(a) providing a substrate having a surface for polishing an object to be polished (step S21);
(b) providing a freely movable high-energy laser (step S22); and
(c) forming a surface texture on the surface of the substrate by using the freely movable high-energy laser(step S23).
In step S21 of the method of the present invention, the substrate is any conventional polishing pad without a surface texture and having a function of polishing (but the polishing effect is not good). Preferably, the material of the substrate is artificial leather, and more preferably, the material of the substrate is a PU plate, a PU and fiber synthetic material, or a PU and micro-fiber synthetic material.
In step S22 of the method of the present invention, the high-energy laser is provided by a freely movable high-energy laser generating apparatus. The detailed manner for providing the high-energy laser is further described below. Preferably, step S23 of the present invention comprises two steps:
(c1) providing a processing pattern; and
(c2) forming a surface texture on the surface of the substrate by using a freely movable high-energy laser according to the processing pattern.
The processing pattern is provided by a data processing apparatus (e.g. a computer), and is designed by the user in advance. The data processing apparatus is electrically connected to the high-energy laser generating apparatus, such that the high-energy laser generating apparatus can form a surface texture on the surface of the substrate with the high-energy laser according to the processing pattern. The processing pattern comprises, but is not limited to, the following patterns: 1. a graphic of squares formed by crossed straight lines; 2. a graphic of squares formed by crossed straight lines and containing a plurality of small round holes; 3. a graphic of concentric circles; 4. a graphic of concentric circles containing a plurality of small round holes; and 5. a graphic of letters or symbols.
The “surface texture” used herein refers to a texture or pattern having a plurality of grooves or round holes on the surface of the substrate, which is formed by removing a part volume of the substrate through a laser processing according to the processing pattern. The surface texture corresponds to the processing pattern, and the top view thereof comprises, but is not limited to, the following patterns: 1. a plurality of straight grooves vertically interlaced with each other (corresponding to the first processing pattern described above); 2. a plurality of straight grooves vertically interlaced with each other and containing a plurality of holes (corresponding to the second processing pattern described above); 3. a plurality of circular grooves with different radii, wherein the circular grooves is concentric (corresponding to the third processing pattern described above); 4. a graphic of concentric circles containing a plurality of holes (corresponding to the fourth processing pattern described above); and 5. a plurality of grooves with a profile of letters or symbols (corresponding to the fifth processing pattern).
Referring to
In this embodiment, the positions of the platform 31 and the laser device 32 are fixed. Two ends of the high-energy laser 35 are a starting end 351 and a processing end 352 respectively, wherein the starting end 351 is emitted by the laser device 32, and the processing end 352 is used to touch and process the substrate 34. The high-energy laser is of a straight line appearance from the starting end 351 to the processing end 352, and the laser head 321 is rotatable, and therefore, the processing end can perform a circumferential movement to form an arc or circular groove. In the surface texture processed by a processing apparatus of this embodiment, there is an inclined angle between the walls of the grooves and the vertical direction of the surface of the substrate. For example, in the third surface texture of concentric circles described above, the inclined angles between the wall of each circular groove and the vertical direction of the surface of the substrate are different, and the inclined angles increase from the inside circular groove to the outside circular groove.
Referring to
In this embodiment, the position of the platform 41 is fixed, while the laser device 42 is movable in a horizontal direction. Two ends of the high-energy laser 45 are a starting end 451 and a processing end 452 respectively, wherein the starting end 451 is emitted by the laser device 42, and the processing end 452 is used to touch and process the substrate 44. The high-energy laser 45 is of a straight line appearance from the starting end 451 to the processing end 452. During the movement of the laser device 42, the high-energy laser 45 is kept vertical to the surface 441 of the substrate 44, thereby forming straight grooves. The walls of the grooves are substantially vertical to the surface of the substrate.
Referring to
In this embodiment, the positions of the platform 51 and the laser device 52 are fixed. Two ends of the high-energy laser 55 are a starting end 551 and a processing end 552 respectively, wherein the starting end 551 is emitted from the laser device 52, and the processing end 552 is used to touch and process the substrate 54. The high-energy laser 55 includes a plurality of sections from the starting end 551 to the processing end 552, wherein the sections have different directions. In this embodiment, the reflecting apparatus 56 comprises one or more mirrors, and the mirror(s) are movable or rotatable. Therefore, the processing end 552 can be rapidly reflected to a desired position. However, it should be understood that the reflecting apparatus 56 can also be another apparatus having a reflection function.
The present invention further relates to a polishing pad having a surface texture, which comprises a substrate and a surface texture. The substrate has a surface for polishing an object to be polished. The surface texture is formed on the surface of the substrate by a freely movable high-energy laser.
Preferably, the material of the substrate is artificial leather, and more preferably, the material of the substrate is a PU plate, a PU and fiber synthetic material, or a PU and micro-fiber synthetic material.
Preferably, the energy of the high-energy laser of the present invention is from 10 W to 85 W, the frequency is from 500 Hz to 10 KHz, and the scanning speed is from 100 mm/sec to 5000 mm/sec. Preferably, the surface texture is formed on a surface of the polishing pad by a high-energy laser according to a processing pattern. The processing pattern is provided by a data processing apparatus (e.g. a computer), and is designed by the user in advance. The processing pattern comprises, but is not limited to, the following patterns: 1. a graphic of squares formed by crossed straight lines; 2. a graphic of squares formed by crossed straight lines and containing a plurality of small round holes; 3. a graphic of concentric circles; 4. a graphic of concentric circles containing a plurality of small round holes; and 5. a graphic of letters or symbols.
The surface texture on the polishing pad is a texture or pattern having a plurality of grooves or round holes, and corresponds to the processing pattern. Therefore, the top view thereof comprises, but is not limited to, the following patterns: 1. a plurality of straight grooves vertically interlaced with each other (corresponding to the first processing pattern described above); 2. a plurality of straight grooves vertically interlaced with each other and containing a plurality of holes (corresponding to the second processing pattern described above); 3. a plurality of circular grooves with different radii, wherein the circular grooves are concentric (corresponding to the third processing pattern described above); 4. a graphic of concentric circles containing a plurality of holes (corresponding to the fourth processing pattern described above); and 5. a plurality of grooves with a profile of letters or symbols (corresponding to the fifth processing pattern).
In the present invention, the walls of the grooves are usually all vertical to the surface of the substrate. However, under some particular circumstances, there is an inclined angle between the walls of the grooves and the vertical direction of the surface of the substrate. For example, in the third surface texture of concentric circles described above, the inclined angles between the wall of each circular groove and the vertical direction of the surface of the substrate are different and increase from the inside to the outside.
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 1At first, a substrate is provided, which has a surface for polishing an object to be polished. The material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of squares formed by crossed straight lines. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 850 mm/sec, a frequency of 10 kHz, and an energy of 37 W.
Referring to
At first, a substrate is provided. The substrate has a surface for polishing an object to be polished, and the material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of squares formed by crossed straight lines and containing a plurality of small round holes. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 430 mm/sec, a frequency of 10 kHz, and an energy of 35 W.
Referring to
At first, a substrate is provided. The substrate has a surface for polishing an object to be polished, and the material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of concentric circles. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 2000 mm/sec, a frequency of 10 kHz, and an energy of 32 W.
Referring to
At first, a substrate is provided. The substrate has a surface for polishing an object to be polished. The material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of concentric circles including a plurality of small round holes. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 2000 mm/sec, a frequency of 10 kHz, and an energy of 32 W.
Referring to
At first, a substrate is provided. The substrate has a surface for polishing an object to be polished. The material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of concentric circles, a plurality of radial straight lines, and a plurality of small round holes. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 2000 mm/sec, a frequency of 10 kHz, and an energy of 32 W.
Referring to
In
At first, a substrate is provided. The substrate has a surface for polishing an object to be polished. The material of the substrate is PU artificial leather. Then, a processing pattern is set in a computer. The processing pattern of this example is a graphic of concentric circles. And then, a high-energy laser is provided. The parameters of the high-energy laser of this example include a scanning speed of 2000 mm/sec, a frequency of 10 kHz, and an energy of 30 W.
The surface of the PU artificial leather is carved by the outputs of the parameters of the high-energy laser and the processing pattern in the computer, thereby forming a circular polishing pad with a diameter of 51 cm having a surface texture. The surface texture comprises a plurality of circular grooves with different radii, wherein the circular grooves are concentric. From a top view, the grooves are 75 concentric circles, and the pitch of the neighboring concentric circles is 2.8 mm. It is measured by a SEM that the width of the grooves is 0.8 mm, and the depth is 0.45 mm. Different from the Example 3, in this example, there is an inclined angle between the walls of the grooves and the vertical direction of the surface of the PU artificial leather, and the inclined angles between the wall of each circular grooves and the vertical direction of the surface of the substrate are different. The inclined angles increase from the inside circular groove to the outside circular groove, wherein the innermost inclined angle is 0 degree (as shown in
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 method for fabricating a polishing pad having a surface texture, comprising the following steps:
- (a) providing a substrate having a surface for polishing an object to be polished;
- (b) providing a freely movable high-energy laser; and
- (c) forming a surface texture on the surface of the substrate by using the freely moveable high-energy laser.
2. The fabricating method as claimed in claim 1, wherein the substrate is a polishing pad without a surface texture, and the material thereof is selected from a group consisting of a free PU plat, a PU and fiber synthetic material, and a PU and micro-fiber synthetic material.
3. The fabricating method as claimed in claim 1, wherein two ends of the high-energy laser of the step (b) are a starting end and a processing end respectively, the starting end is emitted by a high-energy laser generating apparatus in a fixed position, the processing end is used to touch and process the substrate and performs a circular movement, and the high-energy laser has a straight line appearance.
4. The fabricating method as claimed in claim 1, wherein two ends of the high-energy laser of the step (b) are a starting end and a processing end respectively, the starting end is emitted by a high-energy laser generating apparatus in a movable position, the processing end is used to touch and process the substrate, and the high-energy laser has a straight line appearance and is kept vertical to the surface of the substrate when moving.
5. The fabricating method as claimed in claim 1, wherein two ends of the high-energy laser of the step (b) are a starting end and a processing end respectively, the starting end is emitted from a high-energy laser generating apparatus in a fixed position, the processing end is used to touch and process the substrate, and the high-energy laser includes a plurality of sections having different directions respectively.
6. The fabricating method as claimed in claim 1, wherein the step (c) comprises:
- (c1) providing a processing pattern; and
- (c2) forming a surface texture on the surface of the polishing pad by using the high-energy laser according to the processing pattern.
7. The fabricating method as claimed in claim 1, wherein the surface texture comprises a plurality of straight grooves interlaced with each other, and the straight grooves have a plurality of crossing points.
8. The fabricating method as claimed in claim 7, wherein the surface texture further comprises a plurality of holes which are located on the crossing points.
9. The fabricating method as claimed in claim 1, wherein the surface texture comprises a plurality of circular grooves with different radii, the circular grooves are concentric, there is an inclined angle between the walls of the circular grooves and the vertical direction of the surface of the substrate, and the inclined angles of the circular grooves increase from the inside circular groove to the outside circular groove.
10. An apparatus for fabricating a polishing pad having a surface texture, comprising:
- a platform, for carrying a substrate having a surface for polishing an object to be polished;
- a high-energy laser generating apparatus, for generating a high-energy laser; and
- a reflecting apparatus, for reflecting the high-energy laser to the surface of the substrate, so as to form a surface texture on the surface of the substrate.
11. The fabricating apparatus as claimed in claim 10, further comprising a data processing apparatus for generating a processing pattern, so as to control the high-energy laser generating apparatus and the reflecting apparatus.
12. The fabricating apparatus as claimed in claim 10, wherein the position of the platform is fixed.
13. The fabricating apparatus as claimed in claim 10, wherein the position of the high-energy laser generating apparatus is fixed.
14. The fabricating apparatus as claimed in claim 10, wherein two ends of the high-energy laser are a starting end and a processing end respectively, the starting end is emitted by the high-energy laser generating apparatus, the processing end is used to touch and process the substrate, and the high-energy laser includes a plurality of sections having different directions.
15. The fabricating apparatus as claimed in claim 10, wherein the reflecting apparatus is a mirror.
16. The fabricating apparatus as claimed in claim 10, wherein the reflecting apparatus comprises a plurality of mirrors.
17. A polishing pad having a surface texture, comprising:
- a substrate, having a surface for polishing an object to be polished; and
- a surface texture, located on the surface of the substrate, and the surface texture having a plurality of grooves and a plurality of holes, wherein the grooves are interlaced to form a plurality of crossing points and the holes are located on the crossing points.
18. The polishing pad as claimed in claim 17, wherein the grooves are straight grooves, and are interlaced with each other to form the crossing points.
19. The polishing pad as claimed in claim 17, wherein the grooves comprise a plurality of straight grooves and a plurality of circular grooves with different radii, and the straight grooves are radial and interlaced with the circular grooves, thus forming the crossing points.
20. A polishing pad having a surface texture, comprising:
- a substrate, having a surface for polishing an object to be polished; and
- a surface texture, located on the surface of the substrate, and the surface texture having a plurality of circular grooves with different radii and a plurality of holes, wherein the circular grooves are concentric, the holes are located on the circular grooves, and the distribution density of the holes increases from the inside circular groove to the outside circular groove.
21. A polishing pad having a surface texture, comprising:
- a substrate, having a surface for polishing an object to be polished; and
- a surface texture, located on the surface of the substrate, and the surface texture having a plurality of circular grooves with different radii, wherein the circular grooves are concentric, there is an inclined angle between the walls of the circular grooves and the vertical direction of the surface of the polishing pad, and the inclined angles of the circular grooves increase from the inside circular groove to the outside circular groove.
22. The polishing pad as claimed in claim 21, wherein the surface texture further comprises a plurality of holes.
23. The polishing pad as claimed in claim 21, wherein the inclined angle of the innermost circular groove is 0 degree.
Type: Application
Filed: Feb 24, 2006
Publication Date: Aug 30, 2007
Inventors: Chung-Ching Feng (Kaohsiung County), Chen-Hsiang Chao (Kaohsiung County), I-Peng Yao (Kaohsiung County), Yung-Chang Hung (Kaohsiung County)
Application Number: 11/360,412
International Classification: B24B 1/00 (20060101); B24D 11/00 (20060101);