U.S. patent application number 17/363489 was filed with the patent office on 2022-04-14 for polishing pad conditioner and manufacturing method thereof.
The applicant listed for this patent is KINIK COMPANY. Invention is credited to Chin-Chung Chou, Jui-Lin Chou, Chun-Kai Tang, Pin-Hsien Wang, Min-Hung Wu.
Application Number | 20220111488 17/363489 |
Document ID | / |
Family ID | 1000005725728 |
Filed Date | 2022-04-14 |
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United States Patent
Application |
20220111488 |
Kind Code |
A1 |
Chou; Jui-Lin ; et
al. |
April 14, 2022 |
POLISHING PAD CONDITIONER AND MANUFACTURING METHOD THEREOF
Abstract
The present invention relates to a polishing pad conditioner and
a manufacturing method thereof. The polishing pad conditioner
includes a substrate, an abrasive layer and a protective layer. The
abrasive layer covers the surface of the substrate. The abrasive
layer includes a bonding layer and a plurality of abrasive
particles embedded in the bonding layer. Each of the abrasive
particles has a protrusion exposed out of the bonding layer, and
the protrusion is insulated. The protective layer covers the
surface of the bonding layer, and the protrusion is exposed out of
the protective layer. The polishing pad conditioner of the present
invention can protect the bonding layer from being damaged by
abrasion and hold the abrasive particles, avoid the abrasive
particles from falling off or out of position, and maintain the
polishing effect and service life of the polishing pad
conditioner.
Inventors: |
Chou; Jui-Lin; (New Taipei
City, TW) ; Wu; Min-Hung; (New Taipei City, TW)
; Chou; Chin-Chung; (New Taipei City, TW) ; Wang;
Pin-Hsien; (New Taipei City, TW) ; Tang;
Chun-Kai; (New Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KINIK COMPANY |
New Taipei City |
|
TW |
|
|
Family ID: |
1000005725728 |
Appl. No.: |
17/363489 |
Filed: |
June 30, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B24B 37/245 20130101;
B24B 37/22 20130101; B24D 3/004 20130101; B24B 53/001 20130101;
B24B 53/017 20130101 |
International
Class: |
B24B 53/017 20060101
B24B053/017; B24B 53/00 20060101 B24B053/00; B24B 37/24 20060101
B24B037/24; B24B 37/22 20060101 B24B037/22; B24D 3/00 20060101
B24D003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 14, 2020 |
TW |
109135518 |
Claims
1. A polishing pad conditioner, comprising: a substrate; an
abrasive layer covering a surface of the substrate, wherein the
abrasive layer includes a bonding layer and a plurality of abrasive
particles embedded in the bonding layer, each of the abrasive
particles has a protrusion exposed out of the bonding layer, and
the protrusion is insulated; and a protective layer covering a
surface of the bonding layer, wherein the protrusion is exposed
outside the protective layer.
2. The polishing pad conditioner of claim 1, wherein the protective
layer is formed by an electrodeposition coating composition;
wherein the electrodeposition coating composition includes a main
resin, and the main resin is epoxy resin, acrylic resin,
polybutadiene resin, polyester resin or polyamide resin.
3. The polishing pad conditioner of claim 1, wherein the substrate
is a metal substrate, a metal alloy substrate, a stainless steel
substrate, or a mold steel substrate.
4. The polishing pad conditioner of claim 1, wherein the bonding
layer is made of brazing material, electroplating material, ceramic
material, metal material or polymer material.
5. The polishing pad conditioner of claim 1, wherein the abrasive
particles are at least one abrasive particles selected from a group
consisting of natural diamond, synthetic diamond, polycrystalline
diamond, cubic boron nitride, aluminum oxide, and silicon
carbide.
6. The polishing pad conditioner of claim 1, which has a cutting
rate (CR.sub.completed), wherein the variation rate between the
cutting rate (CR.sub.completed) and the cutting rate
(CR.sub.initial) of a polishing pad conditioner that is not covered
with a protective layer is less than 10%.
7. A method for manufacturing a polishing pad conditioner, the
steps of which include: (a) providing a substrate; (b) forming an
abrasive layer on a surface of the substrate, wherein the abrasive
layer includes a bonding layer and a plurality of abrasive
particles embedded in the bonding layer, and each abrasive particle
has a protrusion exposed above the bonding layer; (c) subjecting
the protrusions to an insulation treatment; and (d)
electrodepositing a protective layer on a surface of the bonding
layer, and exposing the insulated protrusions outside the
protective layer.
8. The method of claim 7, wherein the insulation treatment includes
physical insulation or chemical insulation.
9. The method of claim 8, wherein the physical insulation includes
sandblasting insulation or plasma insulation.
10. The method of claim 8, wherein the chemical insulation includes
etching insulation.
11. The method of claim 10, wherein the etching insulation includes
etching with a chemical solution, wherein the chemical solution
includes at least one selected from a group consisting of nitric
acid, aqua regia, hydrofluoric acid, sulfuric acid, hydrogen
peroxide, perchloric acid, hydrochloric acid, ferric chloride,
acetic acid, and ammonium cerium nitrate.
12. The method of claim 7, wherein the bonding layer is formed by
an electroplating method or a brazing method.
Description
BACKGROUND OF THE INVENTION
1. Technical Field
[0001] The present invention relates to a polishing pad conditioner
and a manufacturing method thereof. The polishing pad conditioner
is particularly used for chemical mechanical polishing (CMP).
2. Description of Related Art
[0002] Chemical mechanical polishing (CMP) is a very important
process in the semiconductor manufacturing process. In addition to
producing wafers of appropriate size, CMP can flatten the surface
of the wafer to facilitate subsequent production of integrated
circuits. Polishing slurry and polishing pad are used in CMP. The
polishing slurry is corrosive, and the particles in it can fill the
fine grooves of the polishing pad. After these particles are fixed,
they provide mechanical friction when the polishing pad rotates to
polish the wafer so as to reduce the roughness of the wafer surface
and achieve a polishing effect.
[0003] However, after a period of use, debris and hardened
polishing slurry will accumulate on the surface of the polishing
pad and cause "glazing" or hardening, that is, the fine grooves are
filled with the hardened polishing slurry and cannot hold the
particles in the newly filled polishing slurry, thereby reducing
the polishing effect. In addition, when the polishing slurry on the
surface of the polishing pad hardens to a certain extent,
protrusions will be generated, and the protrusions will destroy the
overall roughness of the wafer surface during polishing, resulting
in failure to achieve the wafer flattening effect. Therefore, the
polishing pad needs to be fixed and dressed with a polishing pad
conditioner (also known as a polishing pad adjuster or a diamond
disc) to remove surface accumulations and restore the original
working surface of the polishing pad, thereby extending the service
life of the polishing pad and reducing replacement cost.
BRIEF SUMMARY OF THE INVENTION
[0004] However, the working surface of the polishing pad
conditioner used for polishing carries abrasive particles. After a
long time of polishing, the working surface cannot hold the
abrasive particles due to wear, causing the abrasive particles to
fall off and be out of place. If the shed abrasive particles remain
on the polishing pad, the wafer will be scratched, and the off-site
abrasive particles will make the polishing pad unevenly trimmed,
thereby affecting the CMP process. Therefore, how to protect the
surface of the polishing pad conditioner from wear and maintain the
quality of the abrasive particles is a problem to be solved by the
technology of the polishing pad conditioner.
[0005] In view of the above problems, the objective of the present
invention is to provide a polishing pad conditioner, which includes
a substrate, an abrasive layer and a protective layer. The abrasive
layer covers the surface of the substrate. The abrasive layer
includes a bonding layer and a plurality of abrasive particles
embedded in the bonding layer. Each of the abrasive particles has a
protrusion exposed out of the bonding layer, and the protrusion is
insulated. The protective layer covers the surface of the bonding
layer, and the protrusion is exposed out of the protective
layer.
[0006] In a preferred embodiment, the protective layer is formed by
an electrodeposition coating composition; wherein the
electrodeposition coating composition includes a main resin, and
the main resin is epoxy resin, acrylic resin, polybutadiene resin,
polyester resin or polyamide resin.
[0007] In a preferred embodiment, the substrate is a metal
substrate, a metal alloy substrate, a stainless steel substrate, or
a mold steel substrate.
[0008] In a preferred embodiment, the bonding layer is made of
brazing material, electroplating material, ceramic material, metal
material or polymer material.
[0009] In a preferred embodiment, the abrasive particles are at
least one abrasive particles selected from a group consisting of
natural diamond, synthetic diamond, polycrystalline diamond, cubic
boron nitride, aluminum oxide, and silicon carbide.
[0010] In a preferred embodiment, the polishing pad conditioner has
a cutting rate (CR.sub.completed). Compared with the cutting rate
(CR.sub.initial) of a polishing pad conditioner that has not been
covered with a protective layer, it conforms to the following
formula:
( C .times. .times. R initial - C .times. .times. R completed ) C
.times. .times. R initial .times. 100 .times. % < 10 .times. % ,
##EQU00001##
that is, the variation rate between the cutting rate
(CR.sub.completed) and the cutting rate (CR.sub.initial) of the
polishing pad conditioner that is not covered with the protective
layer is less than 10%.
[0011] Another objective of the present invention is to provide a
method for manufacturing a polishing pad conditioner, the steps of
which include: (a) providing a substrate; (b) forming an abrasive
layer on the surface of the substrate, wherein the abrasive layer
includes a bonding layer and a plurality of abrasive particles
embedded in the bonding layer, and each abrasive particle has a
protrusion exposed above the bonding layer; (c) subjecting the
protrusions to an insulation treatment; and (d) electrodepositing a
protective layer on the surface of the bonding layer, and exposing
the insulated protrusions outside the protective layer.
[0012] In a preferred embodiment, the insulation treatment includes
physical insulation or chemical insulation.
[0013] In a preferred embodiment, the physical insulation includes
sandblasting insulation or plasma insulation.
[0014] In a preferred embodiment, the chemical insulation includes
etching insulation.
[0015] In a preferred embodiment, the etching insulation includes
etching with a chemical solution, wherein the chemical solution
includes at least one selected from a group consisting of nitric
acid, aqua regia, hydrofluoric acid, sulfuric acid, hydrogen
peroxide, perchloric acid, hydrochloric acid, ferric chloride,
acetic acid, and ammonium cerium nitrate.
[0016] In a preferred embodiment, the bonding layer is formed by an
electroplating method or a brazing method.
[0017] Compared with the prior art, the polishing pad conditioner
of the present invention has a protective layer and protrusions of
abrasive particles exposed outside the protective layer. The
protective layer can prevent the metal (e.g., nickel) of the
bonding layer from being precipitated during the CMP process to
prevent contamination, and can protect the bonding layer from
abrasion damage and hold the abrasive particles to prevent the
abrasive particles from falling off or being out of place. And
because the protrusions of the abrasive particles are exposed
outside the protective layer, the polishing effect and lifetime of
the polishing pad conditioner can be maintained. In addition, in
the manufacturing method of the polishing pad conditioner of the
present invention, the protrusions of the abrasive particles are
insulated before the protective layer is electrodeposited so that
the protective layer will not cover the protrusions during
electrodeposition, and the cutting rate of the polishing pad
conditioner can be maintained. Moreover, the protective layer
formed by electrodeposition has the advantages of thin thickness
and uniform distribution, which can not only protect the bonding
layer, but also adjust and maintain the height of the protrusions
as needed.
BRIEF DESCRIPTION OF THE FIGURE
[0018] FIG. 1 shows the polishing pad conditioner of the present
invention.
[0019] FIG. 2 shows the manufacturing method of the polishing pad
conditioner of the comparative example.
[0020] FIG. 3 shows the manufacturing method of the polishing pad
conditioner of the present invention.
[0021] FIG. 4 shows a scanning electron microscope (SEM) photograph
of the surface of the abrasive layer of the polishing pad
conditioner of the Example and that of the Comparative Example 1,
wherein (a) is the surface of the abrasive layer of the polishing
pad conditioner of the Comparative Example 1, and (b) is the
surface of the abrasive layer of the polishing pad conditioner of
the Example.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The following example should not be regarded as excessively
limiting the present invention. Those with ordinary knowledge in
the technical field of the invention can make modifications and
changes to the example discussed herein without departing from the
spirit or scope of the invention, and such modifications and
changes still fall within the scope of the invention.
[0023] The terms "a" and "an" refer to one or to more than one
(i.e., to at least one) of the grammatical object of the
article.
[0024] As shown in FIG. 1, the polishing pad conditioner of the
present invention includes a substrate 1, an abrasive layer 2 and a
protective layer 3. The abrasive layer 2 covers the surface of the
substrate 1. The abrasive layer 2 includes a bonding layer 21 and a
plurality of abrasive particles 22 embedded in the bonding layer
21. Each of the abrasive particles 22 has a protrusion 221 exposed
out of the bonding layer 21, and the protrusion 221 has been
subjected to an insulation treatment. The protective layer 3 covers
the surface of the bonding layer 21, and the protrusion 221 is
exposed outside the protective layer 3.
[0025] FIG. 2 provides a method for manufacturing a polishing pad
conditioner of a comparative example. After the abrasive particles
22 are embedded in the bonding layer 21, a protective layer 3 is
coated on the surfaces of the abrasive particles 22 and the bonding
layer 21. However, the inventor found after many experiments that
when manufacturing a polishing pad conditioner, no matter what
bonding method (such as brazing, electroplating/electrodeposition
or sintering) is used to inlay and fix the abrasive particles 22 on
the bonding layer 21, since the brazing, electroplating or
sintering material remains on the abrasive particles 22, the
abrasive particles 22 will become conductive after being fixed on
the bonding layer 21. Therefore, when the protective layer 3 is
covered on the bonding layer 21 by coating or electrodeposition in
the next step, the abrasive particles 22 are covered by the
protective layer 3 due to their conductivity and cannot be exposed
outside the protective layer 3. Compared with the polishing pad
conditioner without the protective layer 3, the cutting rate of the
polishing pad conditioner with the protective layer 3 is reduced
because the abrasive particles 22 are covered by the protective
layer 3, thereby reducing the overall cutting rate of the polishing
pad conditioner. Moreover, the protective layer 3 covering the
abrasive particles 22 is easy to peel off during the polishing pad
conditioner dressing the polishing pad, causing impurities to fall
on the polishing pad, which affects the polishing quality.
[0026] Different from the manufacturing method of the polishing pad
conditioner of the comparative example, the manufacturing method of
the polishing pad conditioner of the present invention is shown in
FIG. 3, and the steps include: (a) providing a substrate 1; (b)
forming an abrasive layer 2 on the surface of the substrate 1,
wherein the abrasive layer 2 includes a bonding layer 21 and a
plurality of abrasive particles 22 embedded in the bonding layer
21, and each of the abrasive particles 22 has a protrusion 221
exposed above the bonding layer 21; (c) performing an insulation
treatment on the protrusion 221 (the insulation treatment shown in
FIG. 4 takes plasma as an example, and the plasma nozzle 4 is used
to spray the protrusion 221 for insulation treatment, but the
insulation treatment of the invention is not limited to the use of
plasma); and (d) electrodepositing a protective layer 3 on the
surface of the bonding layer 21, and the protrusion 221 after
insulation treatment is exposed outside the protective layer 3.
Since the protrusion 221 is insulated in step (c), its surface has
been completely insulated. When the protective layer 3 is
subsequently electrodeposited in step (d), since electrodeposition
transfers the charged resin particles in the solution to the
surface of the oppositely charged electrode under the action of an
electric field, and the surface of the protrusion 221 is insulated,
the protective layer 3 cannot be formed on the surface of the
protrusion 221. As a result, the protrusion 221 will be exposed
outside the protective layer 3, so that the abrasive particles 22
can maintain the original cutting rate, and the protective layer 3
will not be peeled off during polishing to generate impurities.
Moreover, since the protective layer 3 covers the bonding layer 21,
the bonding layer 21 can be protected from being damaged by
friction during polishing, so that the bonding layer 21 can firmly
hold the abrasive particles 221 and prevent the abrasive particles
221 from falling off or being out of place. In addition, the
polishing slurry in CMP is usually corrosive, such as an acid
etching solution, while the protective layer 3 can protect the
bonding layer 21 from being corroded by the etching solution to
precipitate metals (such as nickel) and prevent contamination.
[0027] After testing, the polishing pad conditioner of the present
invention has a cutting rate (CR.sub.completed). Compared with the
cutting rate (CR.sub.initial) of a polishing pad conditioner that
is not covered with the protective layer 3 (i.e., the bonding layer
21 is not covered with the protective layer 3), the variation rate
of the cutting rate conforms to the following formula:
( C .times. .times. R initial - C .times. .times. R completed ) C
.times. .times. R initial .times. 100 .times. % < 10 .times. % ,
##EQU00002##
that is, the variation rate between the cutting rate
(CR.sub.completed) and the cutting rate (CR.sub.initial) of the
polishing pad conditioner that is not covered with a protective
layer is less than 10%. In the polishing pad conditioner
manufactured by the manufacturing method of the polishing pad
conditioner of the present invention, electrodepositing the
protective layer 3 on the bonding layer 21 has little effect on the
cutting rate of the polishing pad conditioner. The cutting rate of
the polishing pad conditioner of the invention is 300 .mu.m/hr or
more, preferably 320 .mu.m/hr or more, and more preferably 330
.mu.m/hr or more. The above-mentioned cutting rate is merely
exemplary and not restrictive. Those with ordinary knowledge in the
field of the invention can adjust according to requirements to
obtain the required cutting rate of the polishing pad
conditioner.
[0028] The materials and manufacturing methods that can be used to
construct the polishing pad conditioner of the present invention
will be described below. It should be noted that the materials and
techniques disclosed herein are only exemplary, and other materials
and techniques not mentioned can be used without departing from the
scope of the invention.
[0029] In the polishing pad conditioner of the present invention,
the substrate 1 is composed of one or more of stainless steel,
metal material, plastic material, and ceramic material. In fact, as
long as the substrate 1 can support the abrasive layer 2. The
preferred material can be a metal substrate, a metal alloy
substrate, a stainless steel substrate or a mold steel substrate.
Specifically, the metal substrate includes, but is not limited to,
copper, iron, aluminum, titanium, or tin; and the metal alloy
substrate includes, but is not limited to, iron alloy, copper
alloy, aluminum alloy, titanium alloy, or magnesium alloy.
[0030] In the polishing pad conditioner of the present invention,
the bonding layer 21 is the interlayer used to carry the abrasive
particles 22 and is attached to the substrate 1, and the abrasive
particles 22 are mainly embedded and fixed on the bonding layer 21.
The bonding layer 21 can be formed by various different methods,
such as resin organic bonding, electroplating, brazing and
electrodeposition. The material of the bonding layer 21 includes
brazing material, electroplating material, ceramic material, metal
material or polymer material, and the invention is not limited to
these. Specifically, the brazing material, electroplating material
or metal material includes at least one selected from the group
consisting of iron, cobalt, nickel, chromium, manganese, silicon,
aluminum, and combinations thereof. The polymer material includes
epoxy resin, polyester resin, polyacrylic resin or phenol resin.
The ceramic material includes various metal oxides, nitrides,
carbides, borides, silicides, or combinations thereof, such as
silicon carbide, silicon nitride, aluminum nitride, aluminum oxide,
titanium carbide, titanium boride, or boron carbide.
[0031] In the polishing pad conditioner of the present invention,
the abrasive particles 22 are at least one abrasive particles 22
selected from a group consisting of natural diamond, synthetic
diamond, polycrystalline diamond, cubic boron nitride, aluminum
oxide, and silicon carbide. The "protrusion 221 of the abrasive
particle 22" referred to herein is the part of the upper end of the
abrasive particle 22 that is not covered by the protective layer 3,
and its shape can be, but is not limited to, a pyramid shape, a
cone shape, a circular arc shape, a cylinder shape, a knife edge
shape, or a prism shape.
[0032] Herein, "the insulation treatment of the protrusion 221"
means that when the abrasive particles 22 are inlaid and fixed on
the bonding layer 21 through the bonding process, the protrusion
221 of the abrasive particle 22 is made conductive due to the
brazing, electroplating or sintering material remaining on the
protrusion 221 during the bonding process, and therefore the
insulation treatment is further applied to the protrusion 221 after
the bonding process. The insulation treatment includes physical
insulation or chemical insulation. The physical insulation includes
sandblasting insulation or plasma insulation, and the principle is
to use sandblasting or plasma to remove the conductive material on
the protrusion 221 to make it non-conductive. The particle size of
the sandblasting particles used in the sandblasting insulation is
about 50-200 .mu.m. The temperature used in the plasma insulation
is about 150-350.degree. C. The chemical insulation includes
insulation by an etching method, which uses a chemical solution to
etch and remove the conductive material on the protrusion 221. The
chemical solution includes, but is not limited to, nitric acid,
aqua regia, hydrofluoric acid, sulfuric acid, hydrogen peroxide,
perchloric acid, hydrochloric acid, ferric chloride, acetic acid,
ammonium cerium nitrate, potassium chloride, potassium iodide,
ammonium persulfate, ammonium chloride, or a combination thereof.
The chemical solution preferably contains at least one selected
from the group consisting of nitric acid, aqua regia, hydrofluoric
acid, sulfuric acid, hydrogen peroxide, perchloric acid,
hydrochloric acid, ferric chloride, acetic acid, and ammonium
cerium nitrate. After the above-mentioned insulation treatment, the
surface of the protrusion 221 is insulated and not charged, and the
protective layer 3 cannot be electrodeposited on the surface of the
protrusion 221 subsequently, so the protrusion 221 can be exposed
outside the protective layer 3.
[0033] In the polishing pad conditioner of the present invention,
the protective layer 3 is preferably formed of an electrodeposition
coating composition. Electrodeposition is a kind of surface
treatment in which the polishing pad conditioner is immersed in the
electrodeposition coating composition, and the abrasive layer 2 is
placed between the electrodes and provided with current, so that
the electrodeposition coating composition is deposited on the
surface of the bonding layer 21 by electrical action to form a
uniform protective layer 3. Although other surface treatment
methods (such as spray coating or spin coating) can also be used,
the use of electrodeposition coating can obtain a uniform and thin
protective layer 3. The protective layer 3 with a thin thickness
can help maintain a considerable height distance between the
abrasive particles 22 and the protective layer 3 and the cutting
rate of the abrasive particles 22. The thickness of the protective
layer 3 may preferably be, but is not limited to, 10-30 .mu.m, and
the thickness difference of each position is preferably controlled
to be 1.0-3.0 .mu.m, and more preferably 1.5 .mu.m. The
electrodeposition coating composition includes a main resin, and
the main resin is epoxy resin, acrylic resin, polybutadiene resin,
polyester resin or polyamide resin, specifically, amine modified
epoxy resin (e.g., modified epoxy resin containing
diethyltriamine), acrylic resin containing carboxyl and hydroxyl
groups, or epoxidized polybutadiene resin, and the invention is not
limited to these.
EXAMPLE
[0034] The following example provides a manufacturing method of the
polishing pad conditioner of the present invention. It should be
understood that the example is for illustration only and is not
intended to limit the invention.
Example--Polishing Pad Conditioner of the Present Invention in
which the Protrusions are Insulated
[0035] Molten nickel-chromium alloy and diamond particles were used
to form an abrasive layer on the surface of a stainless steel. The
molten nickel-chromium alloy was coated on part of the oblique side
of each diamond particle by surface tension to embed, support, and
fix the diamond particle on the surface of a stainless steel.
Plasma insulation treatment was applied to the protrusion of each
diamond particle to insulate the surface of the protrusion.
Finally, an epoxy resin (PPG Industries Inc.) was electrodeposited
on the surface of the bonding layer to form a protective layer to
obtain the polishing pad conditioner of the present invention.
Comparative Example 1--Polishing Pad Conditioner with Uninsulated
Protrusions
[0036] The manufacturing method of the polishing pad conditioner of
Comparative Example 1 was the same as that of the Example, except
that the protrusion of each diamond particle in Comparative Example
1 was not insulated.
[0037] Test 1--Cutting Rate
[0038] The cutting rate of the polishing pad conditioner of the
Example and that of Comparative Example 1 were tested respectively,
and the variation rate of cutting rate is calculated by the
following formula:
( C .times. .times. R initial - C .times. .times. R completed ) C
.times. .times. R initial .times. 100 .times. % ; ##EQU00003##
and the results are shown in Table 1.
TABLE-US-00001 TABLE 1 Cutting rate when not Cutting rate when
covered Variation covered with protective with protective layer
rate of layer (CR.sub.initial, .mu.m/hr) (CR.sub.completed,
.mu.m/hr) cutting rate Example 325 321 1.23% Comparative 318 202
36.48% Example 1
[0039] As shown in Table 1, after the bonding layer of the
polishing pad conditioner of the Example was covered by the
protective layer, the variation rate of the cutting rate was less
than 10%, which means that the cutting rate of the polishing pad
conditioner of the Example would not decrease even if it was
covered by the protective layer. In contrast, after the abrasive
layer of the polishing pad conditioner of Comparative Example 1 was
covered by the protective layer, the variation rate of the cutting
rate was greater than 10%, which decreased from 318 .mu.m/hr to 202
.mu.m/hr. The difference between the Example and the Comparative
Example 1 lies in whether the protective layer covered the
protrusions of the diamond particles. It can be seen from
Comparative Example 1 that when the protective layer covers the
protrusions, the cutting rate of the polishing pad conditioner is
greatly reduced.
[0040] Test 2--Photographed the Surface of the Abrasive Layer of
the Polishing Pad Conditioner by Scanning Electron Microscope
(SEM)
[0041] A scanning electron microscope (SEM) was used to photograph
the surface of the abrasive layer of the polishing pad conditioner
of the Example and that of Comparative Example 1, and the results
are shown in FIG. 4. FIG. 4(a) is the surface of the abrasive layer
of the polishing pad conditioner of Comparative Example 1, and FIG.
4(b) is the surface of the abrasive layer of the polishing pad
conditioner of the Example. As shown in FIG. 4(b), the protrusions
of the abrasive particles of the polishing pad conditioner of the
Example are insulated, and the protective layer cannot be
electrodeposited on the surface, thus forming a sharper cutting
surface. In contrast, as shown in FIG. 4(a), the protrusions of the
abrasive particles of the polishing pad conditioner of Comparative
Example 1 are not insulated, and the protective layer is
electrodeposited on the surface, thus forming a rounder but not
sharp cutting surface.
Comparative Example 2--Polishing Pad Conditioner without Protective
Layer
[0042] Molten nickel-chromium alloy and diamond particles were used
to form an abrasive layer on the surface of a stainless steel. The
molten nickel-chromium alloy was coated on part of the oblique side
of each diamond particle by surface tension so as to embed, support
and fix the diamond particle to obtain a polishing pad conditioner
without a protective layer.
[0043] Test 3--Comparison of Metal Precipitation
[0044] The polishing pad conditioner of the Example and that of
Comparative Example 2 were soaked in 3% nitric acid solution,
respectively. After 24 hours, the amount of metal in the 3% nitric
acid solution after soaking was tested, and the results are shown
in Table 2.
TABLE-US-00002 TABLE 2 Cr Fe Ni Co (ppb) (ppb) (ppb) (ppb) 3%
HNO.sub.3 16 90 4 n.d Example 39 117 18 3 Comparative 147,071
176,703 334,063 885 Example 2
[0045] As shown in Table 2, 3% nitric acid solution originally
contained low concentrations of chromium, iron, nickel and cobalt.
After the polishing pad conditioner of the Example was soaked,
although chromium, iron, nickel, and cobalt were precipitated, the
concentrations were not high. In contrast, the polishing pad
conditioner of Comparative Example 2 had very high precipitation
concentrations of chromium, iron, nickel, and cobalt because there
was no protective layer.
[0046] According to the above Example, the polishing pad
conditioner manufactured by insulating the protrusions has no
protective layer covering the protrusions of diamond particles, so
the cutting rate can be maintained without reducing the polishing
effect, and the polishing ability of the polishing pad conditioner
is maintained. In addition, when the bonding layer of the polishing
pad conditioner is covered with a protective layer, the metal of
the bonding layer can be protected from precipitation.
[0047] In summary, the polishing pad conditioner of the present
invention has a protective layer, which can prevent the metal
(e.g., nickel) of the bonding layer from being precipitated during
the CMP process to prevent contamination, and protect the bonding
layer from being damaged by abrasion and hold the abrasive
particles, prevent the abrasive particles from falling off or out
of position, and prevent the protective layer from peeling off
during polishing pad conditioner dressing the polishing pad and
causing impurities to fall on the polishing pad, thereby
maintaining the polishing effect and prolonging the service life.
In addition, the manufacturing method of the polishing pad
conditioner of the present invention uses insulation treatment and
electrodeposition. The insulation treatment can insulate the
protrusions of the abrasive particles so that the protective layer
will not cover the protrusions during subsequent electrodeposition.
The protective layer formed by electrodeposition has the advantages
of thin thickness and uniform distribution, so that the height of
the protrusion can be maintained, i.e., the cutting rate of the
polishing pad conditioner can be maintained. Therefore, the
polishing pad conditioner of the invention is suitable for CMP and
has industrial applicability.
[0048] The above is the detailed description of the present
invention. However, the above is merely the preferred Example of
the invention and cannot be the limitation to the implement scope
of the invention, which means the variation and modification
according to the present invention may still fall into the scope of
the invention.
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