U.S. patent application number 11/360412 was filed with the patent office on 2007-08-30 for polishing pad having a surface texture and method and apparatus for fabricating the same.
Invention is credited to Chen-Hsiang Chao, Chung-Ching Feng, Yung-Chang Hung, I-Peng Yao.
Application Number | 20070202780 11/360412 |
Document ID | / |
Family ID | 38444608 |
Filed Date | 2007-08-30 |
United States Patent
Application |
20070202780 |
Kind Code |
A1 |
Feng; Chung-Ching ; et
al. |
August 30, 2007 |
Polishing pad having a surface texture and method and apparatus for
fabricating the same
Abstract
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.
Inventors: |
Feng; Chung-Ching;
(Kaohsiung County, TW) ; Chao; Chen-Hsiang;
(Kaohsiung County, TW) ; Yao; I-Peng; (Kaohsiung
County, TW) ; Hung; Yung-Chang; (Kaohsiung County,
TW) |
Correspondence
Address: |
VOLENTINE & WHITT PLLC
ONE FREEDOM SQUARE
11951 FREEDOM DRIVE SUITE 1260
RESTON
VA
20190
US
|
Family ID: |
38444608 |
Appl. No.: |
11/360412 |
Filed: |
February 24, 2006 |
Current U.S.
Class: |
451/56 ;
451/526 |
Current CPC
Class: |
B23K 26/355 20180801;
B24B 37/26 20130101; B24D 18/00 20130101 |
Class at
Publication: |
451/056 ;
451/526 |
International
Class: |
B24B 1/00 20060101
B24B001/00; B24D 11/00 20060101 B24D011/00 |
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.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] 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.
[0003] 2. Description of the Related Art
[0004] 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.
[0005] Referring to FIG. 1, a method for fabricating a polishing
pad having a surface texture disclosed in ROC Patent Publication
No. 491758 is shown. FIG. 1 shows a screen printing method, and the
steps thereof are described as follows. A flexible substrate 10 is
provided by a roll and in parallel to a screen template 11 provided
by another roll, wherein the screen template 11 has a plurality of
patterns 111. A polymeric material 12 is displaced to touch the
screen template 11, and forced to enter and pass through the
pattern 111 of the screen template 11 by a scraper 13, and touch
the flexible substrate 10. Then, the screen template 11 and the
polymeric material 12 on the flexible substrate 10 pass through an
aging region 14 which may be a baker or a UV radiation, to age the
polymeric material 12 on the flexible substrate 10, thereby forming
an aging coating 15. After being aged, the screen template 11 is
removed and wound. Finally, the obtained flexible substrate 10
having the aging coating 15 is cut into a plurality of polishing
pads.
[0006] 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.
[0007] 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.
[0008] Referring to FIG. 2, an apparatus for fabricating a
polishing pad disclosed in ROC Patent Publication No. 590855 is
shown. The apparatus 2 comprises a platform 21, a laser device 22,
and a computer numerical control controller 23. The platform 21 is
used to carry a substrate 24, and can rotate and move in three
dimensions. The laser device 22 is used to generate a laser 25 to
illuminate the surface of the substrate 24, so as to form a surface
texture on the surface of the substrate 24. The apparatus 2 moves
the platform 21 according to the input pattern 26, such that
various patterns of micropores, holes, or grooves can be formed for
the surface texture. However, as the platform 21 is quite bulky and
insensitive, this results in slow speed, low accuracy, and other
disadvantages when it rotates and moves in three dimensions.
[0009] 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 INVENTION
[0010] The objective of the present invention is to provide a
method for fabricating a polishing pad having a surface texture,
comprising the following steps:
[0011] (a) providing a substrate, which has a surface for polishing
an object to be polished;
[0012] (b) providing a freely movable high-energy laser; and
[0013] (c) forming a surface texture on the surface of the
substrate by using the high-energy laser.
[0014] 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.
[0015] In a preferred embodiment, the step (c) further
comprises:
[0016] (c1) providing a processing pattern; and
[0017] (c2) forming a surface texture on the surface of the
polishing pad by using the high-energy laser according to the
processing pattern.
[0018] 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.
[0019] 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
[0020] FIG. 1 shows a method for fabricating a polishing pad having
a surface texture disclosed in ROC Patent No. 491758;
[0021] FIG. 2 shows an apparatus for fabricating a polishing pad
disclosed in ROC Patent No. 590855;
[0022] FIG. 3 shows a flow of a method for fabricating a polishing
pad having a surface texture according to the present
invention;
[0023] FIG. 4 is a schematic view of an apparatus for fabricating a
polishing pad according to a first embodiment of the present
invention;
[0024] FIG. 5 is a schematic view of an apparatus for fabricating a
polishing pad according to a second embodiment of the present
invention;
[0025] FIG. 6 is a schematic view of an apparatus for fabricating a
polishing pad according to a third embodiment of the present
invention;
[0026] FIG. 7 is a schematic view of a surface texture processed
according to Example 1;
[0027] FIG. 8 is a schematic view of a surface texture processed
according to Example 2;
[0028] FIG. 9 is a schematic view of a surface texture processed
according to Example 3;
[0029] FIG. 10 is a schematic view of a surface texture processed
according to Example 4;
[0030] FIG. 11 is a schematic view of a surface texture processed
according to Example 5;
[0031] FIG. 12a is a sectional view of the innermost circular
groove in Example 6;
[0032] FIG. 12b is a sectional view of the 38th circular groove in
Example 6; and
[0033] FIG. 12c is a sectional view of the outermost circular
groove in Example 6.
DETAILED DESCRIPTION OF THE INVENTION
[0034] 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.
[0035] Referring to FIG. 3, the method for fabricating the
polishing pad of the present invention comprises the flowing
steps:
[0036] (a) providing a substrate having a surface for polishing an
object to be polished (step S21);
[0037] (b) providing a freely movable high-energy laser (step S22);
and
[0038] (c) forming a surface texture on the surface of the
substrate by using the freely movable high-energy laser(step
S23).
[0039] 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.
[0040] 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:
[0041] (c1) providing a processing pattern; and
[0042] (c2) forming a surface texture on the surface of the
substrate by using a freely movable high-energy laser according to
the processing pattern.
[0043] 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.
[0044] 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).
[0045] Referring to FIG. 4, a schematic view of an apparatus for
fabricating a polishing pad according to a first embodiment of the
present invention is shown. The fabricating apparatus 3 comprises a
platform 31, a high-energy laser generating apparatus (e.g. a laser
device 32), and a data processing apparatus 33. The platform 31 is
used to carry a substrate 34 having a surface 341 for polishing an
object to be polished in other processes. In this embodiment, the
high-energy laser generating apparatus is a laser device 32, and
further comprises a laser head 321 for generating a high-energy
laser 35. The data processing apparatus 33 controls the laser
device 32 according to the input processing pattern, such that a
surface texture is formed on the surface 341 by the high-energy
laser 35.
[0046] 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.
[0047] Referring to FIG. 5, a schematic view of an apparatus for
fabricating a polishing pad according to a second embodiment of the
present invention is shown. The fabricating apparatus 4 comprises a
platform 41, a high-energy laser generating apparatus (e.g. a laser
device 42), and a data processing apparatus 43. The platform 41 is
used to carry a substrate 44 having a surface 441 for polishing an
object to be polished in other processes. In this embodiment, the
high-energy laser generating apparatus is a laser device 42 and
further comprises a laser head 421 for generating a high-energy
laser 45. The data processing apparatus 43 controls the laser
device 42 according to the input processing pattern, such that a
surface texture is formed on the surface 441 by the high-energy
laser 45.
[0048] 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.
[0049] Referring to FIG. 6, a schematic view of an apparatus for
fabricating the polishing pad according to a third embodiment of
the present invention is shown. The fabricating apparatus 5
comprises a platform 51, a high-energy laser generating apparatus
(e.g. a laser device 52), a data processing apparatus 53, and a
reflecting apparatus 56. The platform 51 is used to carry a
substrate 54 having a surface 541 for polishing an object to be
polished in other processes. In this embodiment, the high-energy
laser generating apparatus is a laser device 52 and further
comprises a laser head 521 for generating a high-energy laser 55.
The data processing apparatus 53 controls the laser device 52 and
the reflecting apparatus 56 according to the input processing
pattern, such that the high-energy laser 55 is reflected by the
reflecting apparatus 56 to the surface 541 of the substrate 54,
forming a surface texture on the surface 541 of the substrate
54.
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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).
[0055] 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.
[0056] 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
[0057] At 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.
[0058] Referring to FIG. 7, a schematic view of a surface texture
processed in Example 1 is shown. The surface of the PU artificial
leather is carved by the output 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 straight grooves. The walls of the grooves are vertical to the
surface of the PU artificial leather. From a top view, the grooves
are vertically interlaced with each other to form a plurality of
squares, wherein the side length of each square is 2 mm. It is
measured by a scanning electron microscope (SEM) that the width of
the grooves is 0.45 mm, and the depth is 0.6 mm.
EXAMPLE 2
[0059] 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.
[0060] Referring to FIG. 8, a schematic view of a surface texture
processed in Example 2 is shown. 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 straight grooves and includes a plurality of holes. The walls of
the grooves and the holes are vertical to the surface of the PU
artificial leather. From a top view, the grooves are vertically
interlaced with each other to form a plurality of squares, wherein
the side length of each square is 3.1 mm. It is measured by a SEM
that the width of the grooves is 0.45 mm, and the depth is 0.6 mm.
The grooves are vertically interlaced with each other to form a
plurality of crossing points. The holes are located on the crossing
points, and the diameter of each hole is 1.2 mm. The holes enable
the slurry to maintain good flowage without scraping the object to
be polished.
EXAMPLE 3
[0061] 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.
[0062] Referring to FIG. 9, a schematic view of a surface texture
processed in Example 3 is shown. 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. The walls of the grooves are vertical to
the surface of the PU artificial leather. From a top view, the
grooves are 75 concentric circles, and the pitch of the neighboring
concentric circles is 2.9 mm. It is measured by a SEM that the
width of the grooves is 0.8 mm, and the depth is 0.45 mm.
EXAMPLE 4
[0063] 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.
[0064] Referring to FIG. 10, a schematic view of a surface texture
processed in Example 4 is shown. 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 and a plurality of holes,
wherein the circular grooves are concentric. The walls of the
grooves are vertical to the surface of the PU artificial leather.
From a top view, the grooves are 75 concentric circles, and the
pitch of the neighboring concentric circles is 2.9 mm. It is
measured by a SEM that the width of the grooves is 0.8 mm, and the
depth is 0.45 mm. The holes are located on the circular grooves,
and the diameter of each hole is 1.5 mm. The holes enable the
slurry to maintain good flowage without scraping the object to be
polished. The distribution manner of the holes is that a larger
number of holes are on the more outer circular groove more densely,
that is, the distribution density of the holes increases from the
inside circular groove to the outside circular groove. In FIG. 10,
there is no hole on the innermost circular groove, i.e. the first
circle, and there are two equidistant holes on the second circle,
2.sup.(3-1) equidistant holes on the third circle, 2.sup.(4-1)
holes on the fourth circle, 2.sup.(n-1) holes on the nth
equidistant circle, and so on.
EXAMPLE 5
[0065] 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.
[0066] Referring to FIG. 11, a schematic view of a surface texture
processed in Example 5 is shown. 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, a plurality of straight
grooves, and a plurality of holes, wherein the circular grooves are
concentric, and the straight grooves are radial, and the straight
grooves intersect the circular grooves to form crossing points.
Some of the holes are located on the crossing points, and the other
holes are on the circular grooves.
[0067] In FIG. 11, the pitch between two neighboring concentric
circles is 2.9 mm. It is measured by a SEM that the width of the
grooves is 0.8 mm, and the depth is 0.45 mm. The diameter of each
hole is 1.5 mm. The holes enable the slurry to maintain a good
flowage without scraping the object to be polished. The
distribution manner of the holes is that a larger number of holes
are on the more outer circular groove, that is, the distribution
density of the holes increases from the inside circular groove to
the outside circular groove.
EXAMPLE 6
[0068] 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.
[0069] 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 FIG. 12a); the inclined angle .alpha..sub.1 of
the 38th groove in the middle is 10 degrees (as shown in FIG. 12b);
and the inclined angle .alpha..sub.2 of the outermost groove is 20
degrees (as shown in FIG. 12c).
[0070] 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.
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