U.S. patent application number 14/676992 was filed with the patent office on 2015-10-08 for chemical mechanical polishing conditioner having different heights.
The applicant listed for this patent is KINIK COMPANY. Invention is credited to CHIA-FENG CHIU, JUI-LIN CHOU, WEN-JEN LIAO, CHIA-CHUN WANG.
Application Number | 20150283672 14/676992 |
Document ID | / |
Family ID | 54208947 |
Filed Date | 2015-10-08 |
United States Patent
Application |
20150283672 |
Kind Code |
A1 |
CHOU; JUI-LIN ; et
al. |
October 8, 2015 |
CHEMICAL MECHANICAL POLISHING CONDITIONER HAVING DIFFERENT
HEIGHTS
Abstract
The present invention relates to a chemical mechanical polishing
conditioner having different heights, comprising: a substrate; a
binding layer disposed on the substrate; and multiple abrasive
units placed on the binding layer. Each abrasive unit has an
abrasive unit substrate and an abrasive layer which is a diamond
film formed by chemical vapor deposition and has multiple abrasive
tips. The abrasive units have a first tip height and a second tip
height. The first tip height is different from the second tip
height. The chemical mechanical polishing conditioner can adjust
the surface roughness of the pad to be polished and improve the
drainage of abrasive slurry.
Inventors: |
CHOU; JUI-LIN; (NEW TAIPEI
CITY, TW) ; WANG; CHIA-CHUN; (NEW TAIPEI CITY,
TW) ; CHIU; CHIA-FENG; (NEW TAIPEI CITY, TW) ;
LIAO; WEN-JEN; (NEW TAIPEI CITY, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KINIK COMPANY |
Taipei |
|
TW |
|
|
Family ID: |
54208947 |
Appl. No.: |
14/676992 |
Filed: |
April 2, 2015 |
Current U.S.
Class: |
451/443 |
Current CPC
Class: |
B24B 53/017
20130101 |
International
Class: |
B24B 53/017 20060101
B24B053/017 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 8, 2014 |
TW |
103112815 |
Claims
1. A chemical mechanical polishing conditioner having different
heights comprising: a substrate; a binding layer disposed on the
substrate; multiple abrasive units placed on the binding layer,
each abrasive unit having an abrasive layer and an abrasive unit
substrate, the abrasive layer being a diamond film formed on the
abrasive unit substrate by chemical vapor deposition and having
multiple abrasive tips; wherein the abrasive units have a first tip
height and a second tip height, and the first tip height is
different from the second tip height.
2. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein a height difference between
the first tip height and the second tip height is 5 micrometers to
100 micrometers, inclusive.
3. The chemical mechanical polishing conditioner having different
heights as claimed in claim 2, wherein the height difference
between the first tip height and the second tip height is 15
micrometers to 60 micrometers, inclusive.
4. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the abrasive units have a
third tip height and a fourth tip height.
5. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the abrasive tips are in the
shape of knife edges, cones, arcs, cylinders, pyramids, or
prisms.
6. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein alignment directions of the
abrasive tips are uniform, partially uniform, or different.
7. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein tip angles of the abrasive
tips are equal, partially equal, or different.
8. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein horizontal distances between
any two neighboring abrasive tips are equal, partially equal, or
different.
9. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein thicknesses of the abrasive
units are equal, partially equal, or different.
10. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein a middle layer is disposed
between the abrasive layer and the abrasive unit substrate.
11. The chemical mechanical polishing conditioner having different
heights as claimed in claim 10, wherein the middle layer is made of
the group consisting of aluminum oxide, silicon carbide, and
aluminum nitride.
12. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the abrasive unit substrate
is a conductive substrate or an insulating substrate.
13. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the binding layer is made of
a ceramic material, a brazing material, an electroplating material,
a metallic material, or a polymeric material.
14. The chemical mechanical polishing conditioner having different
heights as claimed in claim 13, wherein the polymeric material is
epoxy resin, polyester resin, polyacrylate resin, or phenol
resin.
15. The chemical mechanical polishing conditioner having different
heights as claimed in claim 13, wherein the brazing material is
made of the group consisting of iron, cobalt, nickel, chromium,
manganese, silicon, aluminum, and any combination thereof.
16. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the substrate is a stainless
steel substrate, a die steel substrate, a metal alloy substrate, a
ceramic substrate, a plastic substrate, or any combination
thereof.
17. The chemical mechanical polishing conditioner having different
heights as claimed in claim 1, wherein the substrate is a flat
substrate or a notch substrate.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a chemical mechanical
polishing conditioner having different heights, especially to a
combinational chemical mechanical polishing conditioner having
different heights.
[0003] 2. Description of the Prior Art(s)
[0004] Chemical Mechanical Polishing (abbreviated as CMP) is
commonly used in various industries to polish the surfaces of
various articles made of ceramic, silicon, glass, quartz, or metal.
With the applicability of large-scaled planarization of integrated
semiconductor device, CMP becomes a common planarization technique
in the semiconductor process.
[0005] During the CMP process of the semiconductor, a pad is
contacted with a wafer or other semiconductor elements in
conjunction with suitable abrasive slurry to remove impurities or
protruding structures on the surface of the wafer through both
chemical reaction and mechanical force. When the pad has been used
for a period of time, polishing debris produced from the CMP
process will accumulate and stagnate on the surface of the pad,
thereby reducing the polishing effect and efficiency. Therefore, a
chemical mechanical polishing conditioner can be used to dress the
surface of the pad for the desired polishing effect and
efficiency.
[0006] In the preparation of a chemical mechanical polishing
conditioner (abbreviated as CMP conditioner), multiple abrasive
particles are mounted to a binding layer to form an abrasive layer.
The abrasive layer is fixed to a surface of a substrate by brazing
or sintering. Said CMP conditioner is suitable for dressing the
pads; however, in more sophisticated semiconductor process with
line-width below 45 nanometers, the rough surface of the pad that
is too coarse will cause problems such as scratch, local
over-polishing, depression, or non-uniform thickness of the wafer.
As the line-width of integrated semiconductor device is decreasing,
the demand for the planarization of the surface of the wafer is
increasing, and same for the CMP conditioner.
[0007] Taiwan Patent Application Publication No. 201249595
discloses a pad conditioner for CMP comprising a substrate having a
first set of protrusions and a second set of protrusions. The first
set of the protrusions has a first average height and the second
set of the protrusions has a second average height. The first
average height and the second average height are different. The
first set of the protrusions includes multiple protrusions each
having non-flat surfaces on their tops, and so does the second set
of the protrusions. A polycrystalline diamond layer is disposed on
the non-flat surfaces of the first and second sets of the
protrusions. The protrusions can be discriminated by their heights,
predetermined positions, or dimensions of substrates. This prior
invention provides various ways to measure the height of the
protrusions including an average height, a peak-to-valley height,
or a protruding height from a back side of the pad conditioner for
CMP. However, the protrusions and the substrate are integrally
formed, failing to form a totally planarized surface to improve the
abrasion efficiency and prolong lifetime of the CMP
conditioner.
[0008] Taiwan Patent Application Publication No. I228066 discloses
a pad conditioner and a dressing method which provide a uniform
abrasive surface. An abrasive surface 4 is mounted on the edge of a
metal support 2 of the pad conditioner 1. Multiple abrasive
particles of various grain sizes are mounted on the abrasive
surface 4 to form a first abrasive particle group 5 and a second
abrasive particle group 6. An adjustment article 7 is mounted on
the metal support 2 for arbitrarily adjusting the height difference
6 between the front surfaces S1, S2 of the first abrasive particle
group 5 and the second abrasive particle group 6. However, when the
pad conditioner is applied to a pad, the pad conditioner cannot
control an abrasion depth of the pad.
[0009] Furthermore, the abrasive ability of a conventional CMP
conditioner is limited by the crystal structure of the abrasive
particles.
[0010] To overcome the shortcomings, the present invention provides
a CMP conditioner to mitigate or obviate the aforementioned
problems.
SUMMARY OF THE INVENTION
[0011] The main objective of the present invention is providing a
CMP conditioner having different heights by combining small
abrasive units with a large substrate to provide a surface with
improved polishing uniformity and different heights of the abrasive
units, which can prevent thermal deformation of the substrate and
can produce different piercing depths while dressing a pad to form
deep trenches and shallow trenches, which can adjust the surface
roughness of the surface of the pad and improve the drainage of
abrasive slurry, on the surface of the pad.
[0012] To achieve the abovementioned objective, the present
invention provides a CMP conditioner having different heights. The
CMP conditioner having different heights comprises a substrate, a
binding layer disposed on the substrate, and multiple abrasive
units placed on the binding layer. Each abrasive unit has an
abrasive layer and an abrasive unit substrate. The abrasive layer
is a diamond film formed on the abrasive unit substrate by chemical
vapor deposition and has multiple abrasive tips. The abrasive units
have a first tip height and a second tip height. The first tip
height is different from the second tip height. Preferably,
thicknesses of the abrasive units are equal and thickness of the
binding layer is varied. Alternatively, the thicknesses of the
abrasive units are different or partially different and the
thickness of the binding layer is varied.
[0013] A height difference between the first tip height and the
second tip height is 5 micrometers to 100 micrometers, inclusive.
Preferably, the height difference between the first tip height and
the second tip height is 15 micrometers to 60 micrometers,
inclusive. More preferably, the abrasive units have a third tip
height and a fourth tip height.
[0014] Shape of the abrasive tips can be customized by the users'
needs or various polishing conditions. The abrasive tips are in the
shape of, but not limited to, knife edges, cones, arcs, cylinders,
pyramids, or prisms. Preferably, the abrasive tips are in the shape
of pyramids. Alternatively, the abrasive tips are in the shape of
prisms. Alternatively, the abrasive tips are cylindrical in
shape.
[0015] Alignment directions or tip angles of the abrasive tips can
be customized by the users' needs or various polishing conditions.
The alignment directions of the abrasive tip are uniform, partially
uniform, or different. Preferably, the abrasive tips are
perpendicular to a pad to be polished. Alternatively, the abrasive
tips are non-perpendicular to the pad.
[0016] The tip angles of the abrasive tips are equal, partially
equal, or different. Preferably, the tip angles of the abrasive
tips are 60 degrees, 90 degrees, or 120 degrees. Alternatively, the
tip angles of some of the abrasive tips are 60 degrees and the tip
angles of the other abrasive tips are 90 degrees.
[0017] Besides, horizontal distances between any two neighboring
abrasive tips can be customized by the users' needs or various
polishing conditions. The horizontal distances between any two
neighboring abrasive tips are equal, partially equal, or different.
Preferably, the horizontal distances between any two neighboring
abrasive tips are 1.5 times, 2 times, or 3 times larger than an
outer diameter of the abrasive tips. Alternatively, some of the
horizontal distances between two neighboring abrasive tips are 2
times larger than the outer diameter of the abrasive tips and the
other horizontal distances between two neighboring abrasive tips
are 3 times larger than the outer diameter of the abrasive
tips.
[0018] A thickness of the substrate and the thicknesses of the
abrasive units can be customized by the users' needs or various
polishing conditions. The thickness of the substrate ranges from 10
millimeters (abbreviated as mm) to 200 mm. Preferably, the
thickness of the substrate ranges from 60 mm to 100 mm. More
preferably, the thickness of the substrate is 80 mm. The
thicknesses of the abrasive units are equal, partially equal, or
different. Preferably, the thicknesses of the abrasive units range
from 5 mm to 100 mm. More preferably, the thicknesses of the
abrasive units range from 15 mm to 30 mm. More preferably, the
thicknesses of the abrasive units are 20 mm.
[0019] Preferably, a middle layer is disposed between the abrasive
layer and the abrasive unit substrate to improve the binding
strength between the abrasive layer and the abrasive unit
substrate. The middle layer is made of the group consisting of
aluminum oxide, silicon carbide, and aluminum nitride. More
preferably, the middle layer is made of silicon carbide.
[0020] The middle layer can be formed by, but not limited to,
chemical vapor deposition, physical vapor deposition, soldering, or
brazing.
[0021] The abrasive layer is made of monocrystalline diamond or
polycrystalline diamond. Preferably, the abrasive layer is made of
polycrystalline diamond, and a crystal dimension of the abrasive
layer ranges from 5 nanometers to 50 micrometers, inclusive. More
preferably, the crystal dimension of the abrasive layer ranges from
10 nanometers to 20 micrometers, inclusive.
[0022] The abrasive unit substrate is a conductive substrate or an
insulating substrate. The conductive substrate is made of
molybdenum, tungsten, or tungsten carbide. A patterned surface with
multiple surface tips can be formed on the conductive substrate by
electric discharge machining, and the abrasive layer are
successively formed on the surface tips by chemical vapor
deposition to obtain the abrasive tips. Alternatively, a patterned
surface with multiple surface tips can be formed on the insulating
substrate by mechanical polishing or laser processing, and the
abrasive layers are successively formed on the surface tips by
chemical vapor deposition to obtain the abrasive tips.
Alternatively, a surface of the abrasive unit substrate is flat.
The abrasive layer is deposited on the abrasive unit substrate by
chemical vapor deposition and has the abrasive tips. The insulating
substrate is made of a ceramic material or a monocrystalline
material. Preferably, the ceramic material is silicon carbide. The
monocrystalline material is silicon or aluminum oxide.
[0023] The binding layer can be customized by the users' needs or
various polishing conditions. The binding layer is made of, but not
limited to, a ceramic material, a brazing material, an
electroplating material, a metallic material, or a polymeric
material. Preferably, the binding layer is made of a brazing
material. The brazing material is made of the group consisting of
iron, cobalt, nickel, chromium, manganese, silicon, aluminum, and
any combination thereof. Alternatively, the binding layer is made
of a polymeric material. The polymeric material is epoxy resin,
polyester resin, polyacrylate resin, or phenol resin.
[0024] A component or a dimension of the substrate can be
customized by the users' needs or various polishing conditions. The
substrate is a stainless steel substrate, a die steel substrate, a
metal alloy substrate, a ceramic substrate, a plastic substrate, or
any combination thereof. Preferably, the substrate is a stainless
steel substrate.
[0025] Preferably, the substrate is a flat substrate or a notch
substrate. More preferably, the substrate is the flat substrate.
Alternatively, the substrate is the notch substrate.
[0026] With the non-uniform configuration in height, the CMP
conditioner having different heights of the present invention has
the effect of adjusting the surface roughness of the pad and
improving the drainage of abrasive slurry. In summary, the CMP
conditioner having different heights has the abrasive units
assembled onto the substrate prevents both the thermal deformation
of the substrate and polishing non-uniformity, thus renders the pad
a uniform surface after polishing.
[0027] Other objectives, advantages and novel features of the
invention will become more apparent from the following detailed
description when taken in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1A is a side view of a CMP conditioner having different
heights in accordance with Embodiment 1 of the present
invention;
[0029] FIG. 1B is another side view of the CMP conditioner having
different heights in accordance with Embodiment 1 of the present
invention;
[0030] FIG. 2 is a side view of a CMP conditioner having different
heights in accordance with Embodiment 2 of the present
invention;
[0031] FIG. 3 is a side view of a CMP conditioner having different
heights in accordance with Embodiment 3 of the present
invention;
[0032] FIG. 4 is a top view of the CMP conditioner having different
heights in accordance with Embodiment 1 of the present
invention;
[0033] FIG. 5A is a top view of an abrasive unit of a CMP
conditioner having different heights in accordance with Embodiment
1 of the present invention;
[0034] FIG. 5B is a top view of an abrasive unit of a CMP
conditioner having different heights in accordance with Embodiment
4 of the present invention; and
[0035] FIG. 5C is a top view of an abrasive unit of a CMP
conditioner having different heights in accordance with Embodiment
5 of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
[0036] With reference to FIG. 1A, the present invention provides a
chemical mechanical polishing conditioner having different heights
1. The chemical mechanical polishing conditioner having different
heights 1 comprises a substrate 10 made of stainless steel, a
binding layer 11, and multiple abrasive units 12. The substrate 10
is a flat substrate and has a thickness of 80 mm. The binding layer
11 is disposed on the substrate 10. Each abrasive unit 12 has an
abrasive unit substrate 13 and an abrasive layer 14. The abrasive
unit substrate 13 is a ceramic substrate made of silicon carbide.
The abrasive unit substrates 13 have two different thicknesses, 20
mm and 30 mm. A surface of the abrasive unit substrate 13 is a flat
surface and the abrasive layer 14 is successively formed on the
surface tips by chemical vapor deposition to obtain multiple
abrasive tips. The abrasive tips are in the shape of pyramids.
Specifically, with reference to FIG. 5A, the abrasive tips are
continuously arranged on the abrasive unit substrate 13 with an
array pattern. The abrasive tips are in the shape of quadrangular
pyramids. Alignment directions of the abrasive tips are uniform.
Tip angles of the abrasive tips are equal. Besides, the abrasive
units have a first tip height and a second tip height. Besides, the
first tip height is different from the second tip height. With
reference to FIG. 1B, the abrasive units 12 have the first tip
height and the abrasive units 12' have the second tip height. A
height difference H between the first tip height and the second tip
height is 20 micrometers and the first tip height of the abrasive
units 12 is relatively higher than the second tip height of the
abrasive units 12'. When the chemical mechanical polishing
conditioner having different heights 1 is applied to dress a pad,
the abrasive units 12' having the second tip height can produce
shallow trenches, which can adjust the surface roughness of the
pad, on the surface of the pad. The abrasive units 12 having the
first tip height can produce deep trenches, which can improve the
drainage of abrasive slurry, on the surface of the pad. With
reference to FIG. 4, the abrasive units 12, 12' are on the
substrate 10 and the binding layer 11. The abrasive units 12 having
the first tip height are shown in the shape of pyramids with grids
and the abrasive units 12' comprising the second tip height are
shown in the shape of pyramids in white color. The abrasive units
12 are arranged alternately with the abrasive units 12' in an
annular pattern.
Embodiment 2
[0037] With reference to FIG. 2, the CMP conditioner having
different heights 2 in Embodiment 2 is similar with the CMP
conditioner having different heights in Embodiment 1. The
difference between the two embodiments is that the thicknesses of
the abrasive units of the CMP conditioner having different heights
in Embodiment 1 are different and the thickness of the binding
layer of the CMP conditioner having different heights in Embodiment
1 is fixed. However, the thicknesses of the abrasive units of the
CMP conditioner having different heights in Embodiment 2 are equal
and thickness of the binding layer of the CMP conditioner having
different heights in Embodiment 2 is varied. The CMP conditioner
having different heights 2 of the present embodiment comprises the
substrate 20 made of stainless steel, the binding layer 21, and the
abrasive units 22. The substrate 20 is a flat substrate and has a
thickness of 80 mm. The binding layer 21 is disposed on the
substrate 20. Each abrasive unit 22 has the abrasive unit substrate
23 and the abrasive layer 24. The abrasive unit substrate 23 is a
ceramic substrate made of silicon carbide. The thickness of the
abrasive unit substrate 23 is 20 mm. The surface of the abrasive
unit substrate 23 is flat. The abrasive layer 24 is deposited on
the abrasive unit substrate 23 by chemical vapor deposition. The
abrasive layer 24 has the abrasive tips. The abrasive tips are in
the shape of pyramids, specifically, quadrangular pyramids (such as
FIG. 5A). The abrasive tips are continuously arranged on the
abrasive unit substrate 23 with an array pattern. The alignment
directions of the abrasive tips are uniform. The tip angles of the
abrasive tips are equal. The thickness of the binding layer 21 is
varied, which can adjust the heights of the abrasive units 22 to
make the abrasive units 22 form the first tip heights and the
second tip heights. The first tip height is different from the
second tip height.
Embodiment 3
[0038] With reference to FIG. 3, the CMP conditioner having
different heights 3 in Embodiment 3 is similar with the CMP
conditioner having different heights in Embodiment 1. The
difference between the two embodiments is that thicknesses of the
abrasive units of the CMP conditioner having different heights in
Embodiment 1 are different and thickness of the binding layer of
the CMP conditioner having different heights in Embodiment 1 is
fixed. However, the thicknesses of the abrasive units of the CMP
conditioner having different heights in Embodiment 3 are different
and the thickness of the binding layer of the CMP conditioner
having different heights in Embodiment 3 is varied. The CMP
conditioner having different heights 3 of the present embodiment
comprises the substrate 30 made of stainless steel, the binding
layer 31, and the abrasive units 32. The substrate 30 is a flat
substrate and has a thickness of 80 mm. The binding layer 31 is
disposed on the substrate 30. Each abrasive unit 32 has the
abrasive unit substrate 33 and the abrasive layer 34. The abrasive
unit substrate 33 is a ceramic substrate made of silicon carbide.
The abrasive unit substrates 33 have two different thicknesses, 20
mm and 30 mm. A surface of the abrasive unit substrate 33 is a flat
surface and the abrasive layer 34 is successively formed on the
surface tips by chemical vapor deposition to obtain multiple
abrasive tips. The thickness of the binding layer 31 is varied,
which can adjust the heights of the abrasive units 32 to make the
abrasive units 32 form the first tip height, the second tip height,
and the third tip height. The first tip height, the second tip
height, and the third tip height are different.
Embodiment 4
[0039] The CMP conditioner having different heights in Embodiment 4
is similar to the CMP conditioner having different heights in
Embodiment 1. The difference between the two embodiments is that
the abrasive tips of the CMP conditioner having different heights
in Embodiment 1 are in the shape of pyramids and the abrasive tips
of the CMP conditioner having different heights in Embodiment 4 are
in a different shape from the abrasive tips of the CMP conditioner
having different heights in Embodiment 1.
[0040] With reference to FIG. 5A, the abrasive tips 15 of the CMP
conditioner having different heights in Embodiment 1 are in the
shape of pyramids and the abrasive tips 15 of the abrasive layer 14
are continuously arranged on the abrasive unit substrate 13 with an
array pattern. With reference to FIG. 5B, the abrasive tips 35 of
Embodiment 4 are in the shape of prisms, specifically, quadrangle
prisms. The abrasive tips 35 of the abrasive layer 34 are
continuously arranged on the abrasive unit substrate 33 with an
array pattern.
Embodiment 5
[0041] The CMP conditioner having different heights in Embodiment 5
is similar to the CMP conditioner having different heights in
Embodiment 1. The difference between the two embodiments is that
the abrasive tips of the CMP conditioner having different heights
in Embodiment 1 are in the shape of pyramids and the abrasive tips
of the CMP conditioner having different heights in Embodiment 5 are
in a different shape from the abrasive tips of the CMP conditioner
having different heights in Embodiment 1.
[0042] With reference to FIG. 5A, the abrasive tips 15 of the CMP
conditioner having different heights in Embodiment 1 are in the
shape of pyramids and the abrasive tips 15 of the abrasive layer 14
are continuously arranged on the abrasive unit substrate 13 with an
array pattern. With reference to FIG. 5C, the abrasive tips 45 of
Embodiment 5 are cylindrical in shape. The abrasive tips 45 of the
abrasive layer 44 are continuously arranged on the abrasive unit
substrate 43 with an array pattern.
[0043] Even though numerous characteristics and advantages of the
present invention have been set forth in the foregoing description,
together with details of the structure and features of the
invention, the disclosure is illustrative only. Changes may be made
in the details, especially in matters of shape, size, and
arrangement of parts within the principles of the invention to the
full extent indicated by the broad general meaning of the terms in
which the appended claims are expressed.
* * * * *