U.S. patent application number 10/962668 was filed with the patent office on 2005-06-02 for polishing apparatus, polishing method, and semiconductor device fabrication method.
Invention is credited to Fukushima, Dai, Minamihaba, Gaku, Yano, Hiroyuki.
Application Number | 20050118937 10/962668 |
Document ID | / |
Family ID | 34611691 |
Filed Date | 2005-06-02 |
United States Patent
Application |
20050118937 |
Kind Code |
A1 |
Fukushima, Dai ; et
al. |
June 2, 2005 |
Polishing apparatus, polishing method, and semiconductor device
fabrication method
Abstract
According to the present invention, there is provided a
polishing apparatus comprising: a rotatable turntable; a polishing
cloth attached on said turntable; a slurry supply pipe which
supplies a slurry onto said polishing cloth; and a polishing member
which presses an object to be polished against a surface of said
polishing cloth, wherein said polishing cloth once stores the
supplied slurry inside said polishing cloth, and discharges the
slurry when pressed by said polishing member, thereby supplying the
slurry to the surface of the object.
Inventors: |
Fukushima, Dai; (Kanagawa,
JP) ; Minamihaba, Gaku; (Kanagawa, JP) ; Yano,
Hiroyuki; (Kanagawa, JP) |
Correspondence
Address: |
Finnegan, Henderson, Farabow,
Garrett & Dunner, L.L.P.
1300 I Street, N.W.
Washington
DC
20005-3315
US
|
Family ID: |
34611691 |
Appl. No.: |
10/962668 |
Filed: |
October 13, 2004 |
Current U.S.
Class: |
451/60 ;
451/285 |
Current CPC
Class: |
B24B 37/042
20130101 |
Class at
Publication: |
451/060 ;
451/285 |
International
Class: |
B24B 049/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 14, 2003 |
JP |
2003-353393 |
Claims
What is claimed is:
1. A polishing apparatus comprising: a rotatable turntable; a
polishing cloth attached on said turntable; a slurry supply pipe
which supplies a slurry onto said polishing cloth; and a polishing
member which presses an object to be polished against a surface of
said polishing cloth, wherein said polishing cloth once stores the
supplied slurry inside said polishing cloth, and discharges the
slurry when pressed by said polishing member, thereby supplying the
slurry to the surface of the object.
2. An apparatus according to claim 1, wherein when rotated by said
turntable, said polishing cloth diffuses the supplied slurry toward
a periphery inside said polishing cloth.
3. An apparatus according to claim 1, wherein said polishing cloth
has a stacked structure including first and second layers, said
first layer has a plurality of through holes extending from one
surface to the other surface in contact with said second layer, and
said second layer is made of a porous material having open
cells.
4. An apparatus according to claim 3, wherein when the slurry is
supplied to said one surface, said first layer supplies the slurry
to said second layer from said other surface through the through
holes, said second layer once stores the slurry supplied from the
through holes, and discharges the slurry when pressed by said
polishing member, and the discharged slurry oozes out to said one
surface from the through holes in said first layer.
5. An apparatus according to claim 3, wherein said second layer
once stores the slurry directly dropped through the through hole
formed in said first layer immediately below said slurry supply
pipe, and discharges the slurry when pressed by said polishing
member, and the discharged slurry oozes out to said one surface
from the through holes in said first layer.
6. An apparatus according to claim 3, wherein said first and second
layers are made of a polymer-based material.
7. An apparatus according to claim 6, wherein said second layer is
made of a material selected from the group consisting of a
polyurethane-based material, polystyrene-based material, and
silicone-based polymer material.
8. An apparatus according to claim 1, wherein said polishing member
comprises a member which presses the surface of the polishing cloth
on an outer peripheral side of the object to be polished.
9. A polishing method, comprising: attaching a polishing cloth on a
turntable and rotating the polishing cloth; and supplying a slurry
onto the polishing cloth, and pressing an object to be polished
against a surface of the polishing cloth by using a polishing
member, thereby polishing the object, wherein the slurry is once
stored inside the polishing cloth, and discharged and supplied to a
surface of the object when pressed by the polishing member.
10. A method according to claim 9, wherein the slurry supplied onto
the polishing cloth is diffused toward a periphery inside the
polishing cloth by rotating the turntable.
11. A method according to claim 9, wherein when the slurry is to be
supplied, the polishing cloth having a stacked structure including
first and second layers is used, the first layer having a plurality
of through holes extending from one surface to the other surface in
contact with the second layer, and the second layer being made of a
porous material having open cells, when the slurry is supplied onto
the polishing cloth from the first layer of the stacked structure,
the second layer once stores the slurry supplied from the through
holes in the first layer, and discharges the slurry when pressed by
the polishing member, and the discharged slurry oozes out to the
one surface from the through holes in the first layer, and thereby
the slurry is supplied to the surface of the object to be
polished.
12. A method according to claim 11, wherein when the slurry is to
be supplied, the slurry is directly dropped on the second layer
through the through hole formed in a central region of the first
layer.
13. A method according to claim 11, wherein said first and second
layers are made of a polymer-based material.
14. A method according to claim 13, wherein said second layer is
made of a material selected from the group consisting of a
polyurethane-based material, polystyrene-based material, and
silicone-based polymer material.
15. A semiconductor device fabrication method, comprising:
obtaining an object to be polished by depositing a conductive film
above an insulating film formed above a semiconductor substrate, so
as to fill a recess formed in the insulating film; attaching a
polishing cloth on a turntable, and rotating the polishing cloth;
and supplying a slurry onto the polishing cloth, and pressing the
object to be polished against a surface of the polishing cloth by
using a polishing member, thereby polishing the object and removing
the conductive film except for the conductive film in the recess,
wherein when the conductive film is removed, the slurry is once
stored inside the polishing cloth, and discharged and supplied to a
surface of the object while pressed by the polishing member.
16. A method according to claim 15, wherein the slurry supplied
onto the polishing cloth is diffused toward a periphery inside the
polishing cloth by rotating the turntable.
17. A method according to claim 15, wherein when the slurry is to
be supplied, the polishing cloth having a stacked structure
including first and second layers is used, the first layer having a
plurality of through holes extending from one surface to the other
surface in contact with the second layer, and the second layer
being made of a porous material having open cells, when the slurry
is supplied onto the polishing cloth from the first layer of the
stacked structure, the second layer once stores the slurry supplied
from the through holes in the first layer, and discharges the
slurry when pressed by the polishing member, and the discharged
slurry oozes out to the one surface from the through holes in the
first layer, and thereby the slurry is supplied to the surface of
the object to be polished.
18. A method according to claim 17, wherein said first and second
layers are made of a polymer-based material.
19. A method according to claim 18, wherein said second layer is
made of a material selected from the group consisting of a
polyurethane-based material, polystyrene-based material, and
silicone-based polymer material.
20. A method according to claim 15, wherein the conductive film
contains at least a material selected from the group consisting of
aluminum, copper, tungsten, titanium, niobium, tantalum, silver,
vanadium, ruthenium, platinum, silicon, and an oxide, nitride,
boride, and alloy of any of the materials.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims benefit of
priority under 35 USC .sctn.119 from the Japanese Patent
Application No. 2003-353393, filed on Oct. 14, 2003, the entire
contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a polishing apparatus,
polishing method, and semiconductor device fabrication method
including a polishing process.
[0003] In the recent semiconductor device fabrication field, new
fabrication apparatuses have been developed as the degree of
micropatterning of semiconductor elements and the density of
element structures increase.
[0004] Among other fabrication apparatuses, a CMP (Chemical
Mechanical Polishing) apparatus is essential in, e.g., CMP
processes of a DRAM or high-speed logic LSI, i.e., a metal
interconnection formation process, buried element isolation region
formation process, and the like.
[0005] In these processes using the CMP apparatus, it is important
to reduce the use amount of slurry which occupies most of the cost,
in addition to improving the process performance such as the
surface uniformity.
[0006] FIG. 10 shows polishing cloth 100 used in the conventional
polishing technique.
[0007] A slurry is supplied on the polishing cloth 100 in the
direction of an arrow 102. Since the polishing cloth 100 hardly has
a function of storing the slurry inside it, the slurry radially
scatters on the surface of the polishing cloth 100 as indicated by
arrows 103. The polishing cloth 100 is adhered on a turntable (not
shown) by a double-coated adhesive tape, and rotated in the
direction of an arrow 101.
[0008] FIG. 11 is a longitudinal sectional view of the polishing
cloth 100 and an object 111 to be polished in a conventional
polishing apparatus.
[0009] As described above, a slurry supplied onto the surface of
the polishing cloth 100 scatters in the direction of the arrow 103.
The object 111 to be polished is rotated and pressed by a polishing
member 112, and polished when the slurry enters a gap between the
object 111 and polishing cloth 100.
[0010] In this state, the slurry can enter the gap between the
polishing cloth 100 and object 111, so the object 111 can be
polished although it is difficult to evenly supply the slurry onto
the surface of the object 111.
[0011] FIG. 12 is a longitudinal cross sectional view of the
polishing cloth 100 and the object 111 to be polished in another
conventional polishing apparatus.
[0012] In this state, the pressure, indicated by an arrow 114,
which presses a polishing member 113 into the shape of a ring is
high, so almost no gap exists between the polishing cloth 100 and
object 111. This makes it difficult to allow the slurry to enter in
the direction indicated by the arrow 103, and obtain a satisfactory
polishing performance.
[0013] In the conventional general slurry supply method as shown in
FIG. 10, a slurry is dropped onto the polishing cloth 100 placed on
the turntable, and supplied to the whole polishing cloth by the
centrifugal force obtained by the rotation of the turntable,
regardless of whether the polishing apparatus shown in FIG. 11 or
12 is used. Since most of the supplied slurry scatters on the
polishing cloth as described above, less than half the supplied
slurry effectively functions during polishing, and more than half
the supplied slurry is wasted. If it is possible to allow a minimum
necessary amount of slurry to effectively function, the use amount
of slurry can be presumably reduced.
[0014] In the conventional slurry supply method, however, the
supply amount of slurry inevitably varies in accordance with the
distance from the slurry dropping position. Therefore, to polish
the entire surface of a semiconductor wafer as the object 111 to be
polished, an excess slurry must be supplied to ensure a high
process performance, and this increases the cost.
[0015] Also, the reduction in use amount of slurry generally leads
to various process performance deteriorations, e.g., not only the
decrease in surface uniformity and polishing speed, but also the
extension of erosion which worsens the flatness of the polishing
surface and the increase in scratch.
[0016] FIG. 13 shows the polishing speed and erosion as functions
of the flow rate of slurry. As is apparent from this graph, when
the slurry flow rate decreases, the polishing speed lowers, and the
erosion increases.
[0017] By contrast, in the technique disclosed in patent reference
1 presented below, a slurry is supplied from below the polishing
cloth, i.e., from the surface opposite to the polishing surface. In
addition, to reduce the slurry supply amount, area control is
performed by dividing a turntable into four portions, and the
slurry is supplied upward to a wafer when it passes by. Patent
reference 1: Japanese Patent Laid-Open No. 10-94965 Unfortunately,
the control mechanism is complicated, and it is difficult to evenly
supply the slurry to the entire surface of a wafer.
[0018] As described above, it is conventionally impossible to
assure a high process performance with a simple arrangement without
supplying any excess slurry, and this increases the cost.
SUMMARY OF THE INVENTION
[0019] According to one aspect of the present invention, there is
provided a polishing apparatus, comprising:
[0020] a rotatable turntable;
[0021] a polishing cloth attached on said turntable;
[0022] a slurry supply pipe which supplies a slurry onto said
polishing cloth; and
[0023] a polishing member which presses an object to be polished
against a surface of said polishing cloth,
[0024] wherein said polishing cloth once stores the supplied slurry
inside said polishing cloth, and discharges the slurry when pressed
by said polishing member, thereby supplying the slurry to the
surface of the object.
[0025] According to one aspect of the present invention, there is
provided a polishing method, comprising:
[0026] attaching a polishing cloth on a turntable and rotating the
polishing cloth; and
[0027] supplying a slurry onto the polishing cloth, and pressing an
object to be polished against a surface of the polishing cloth by
using a polishing member, thereby polishing the object,
[0028] wherein the slurry is once stored inside the polishing
cloth, and discharged and supplied to a surface of the object when
pressed by the polishing member.
[0029] According to one aspect of the present invention, there is
provided a semiconductor device fabrication method, comprising:
[0030] obtaining an object to be polished by depositing a
conductive film above an insulating film formed above a
semiconductor substrate, so as to fill a recess formed in the
insulating film;
[0031] attaching a polishing cloth on a turntable, and rotating the
polishing cloth; and
[0032] supplying a slurry onto the polishing cloth, and pressing
the object to be polished against a surface of the polishing cloth
by using a polishing member, thereby polishing the object and
removing the conductive film except for the conductive film in the
recess,
[0033] wherein when the conductive film is removed, the slurry is
once stored inside the polishing cloth, and discharged and supplied
to a surface of the object while pressed by the polishing
member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 is a longitudinal cross sectional view showing the
sectional structure of a polishing cloth used in a polishing
apparatus according to the first embodiment of the present
invention;
[0035] FIG. 2 is a longitudinal cross sectional view showing the
movement of a slurry when an object to be polished is polished by
using the polishing cloth shown in FIG. 1;
[0036] FIG. 3 is a perspective view showing an outline of the
overall arrangement of the polishing apparatus shown in FIG. 1;
[0037] FIG. 4 is a graph showing the polishing speed and erosion as
functions of the flow rate of slurry when polishing is performed
using the polishing apparatus shown in FIG. 1;
[0038] FIG. 5 is a longitudinal cross sectional view showing an
element section in a certain process when a semiconductor device is
fabricated by using the polishing apparatus shown in FIG. 1;
[0039] FIG. 6 is a longitudinal cross sectional view showing the
element section in another process when the semiconductor device is
fabricated by using the polishing apparatus shown in FIG. 1;
[0040] FIG. 7 is a longitudinal cross sectional view showing the
sectional structure of a polishing cloth used in a polishing
apparatus according to the second embodiment of the present
invention;
[0041] FIG. 8 is a longitudinal cross sectional view showing an
example of the structure of a polishing member (top ring head)
included in the polishing apparatus;
[0042] FIG. 9 is a longitudinal cross sectional view showing
another example of the structure of the polishing member (top ring
head) included in the polishing apparatus;
[0043] FIG. 10 is a perspective view showing the way a slurry is
dropped onto polishing cloth used in a conventional polishing
apparatus;
[0044] FIG. 11 is a longitudinal cross sectional view showing the
movement of the slurry when polishing is performed using the
conventional polishing apparatus;
[0045] FIG. 12 is a longitudinal cross sectional view showing the
movement of the slurry when polishing is performed using another
conventional polishing apparatus; and
[0046] FIG. 13 is a graph showing the polishing speed and erosion
as functions of the flow rate of slurry when polishing is performed
using the conventional polishing apparatus.
DETAILED DESCRIPTION OF THE INVENTION
[0047] Embodiments of the present invention will be described below
with reference to the accompanying drawings.
(1) FIRST EMBODIMENT
[0048] FIG. 1 shows the longitudinal cross sectional structure of
polishing cloth 10 used in a polishing apparatus according to the
first embodiment.
[0049] The polishing cloth 10 has a first layer 11 and second layer
12. The first layer 11 has a plurality of through holes 13 which
extend from the upper surface to the lower surface in contact with
the second layer 12. The second layer 12 is made of a porous
material having open cells. The first and second layers 11 and 12
are formed by using a polymer material such as polyurethane.
[0050] When a slurry is dropped on the surface of the polishing
cloth 10 in the direction of an arrow 14, it is supplied to the
second layer 12 trough the through holes 13 in the first layer 11.
In the second layer 12, the slurry is diffused toward the
circumference as indicated by arrows 15 by the centrifugal force of
the rotation of a turntable, and once stored.
[0051] In this state, as shown in FIG. 2, an object 21 to be
polished is placed on the surface of the first layer 11, and a
polishing member 22 presses the object 11 in the direction of an
arrow 23, thereby discharging the slurry stored in the second layer
12. Consequently, the slurry is discharged in the direction of
arrows 16 through the through holes 13 in the first layer 11, and
supplied to the contact surface between the surface of the first
layer 11 and the object 21.
[0052] FIG. 8 shows an example of the structure of the polishing
member 22.
[0053] The object 21 to be polished is placed on the polishing
cloth 10, and the polishing member having a housing 201 rotates the
object 21 while pressing it. The housing 201 has a guide ring 205
for holding the object 21, an elastic sheet 204 which comes in
contact with the rear surface of the object 21, and a hollow
portion 203 which improves the uniformity of polishing by applying
an air pressure in the direction of an arrow 211 to the rear
surface of the object 21 via the elastic sheet 204. Also, a load
necessary for polishing is applied to the inside of the housing 201
by applying an air pressure in the direction of an arrow 212.
[0054] FIG. 9 shows another example of the structure of the
polishing member 22. The polishing member 22 shown in FIG. 9 can
apply a more even pressure to the object 21 to be polished.
[0055] That is, the object 21 is placed on the polishing cloth 10,
and the polishing member having a housing 221 rotates the object 21
while pressing it. The housing 221 has an airbag chamber 222,
hollow chamber 223, and retainer ring 224. The airbag chamber 222
is formed by a membrane 235 which is made of hard rubber and comes
in contact with the rear surface of the object 21, and a chucking
plate 234. The airbag chamber 222 applies a load necessary for
polishing when an air pressure is applied in the direction of an
arrow 231. The hollow chamber 223 gives an air pressure for
pressing the chucking plate 234 in the direction of an arrow 232.
The retainer ring 224 retains the object 21 to be polished, and
presses the surface of the polishing cloth 10 into the shape of a
ring in a position separated from the outer circumference of the
object 21 when an air pressure is applied in the direction of an
arrow 233 inside the housing 221.
[0056] The pressure indicated by the arrow 231 is higher than that
indicated by the arrow 233. This improves the uniformity of
polishing.
[0057] FIG. 3 shows an outline of the overall arrangement of a
polishing apparatus usable in the embodiment of the present
invention.
[0058] The polishing cloth 10 is adhered by, e.g., a double-coated
adhesive tape on a turntable 31 which rotates in the direction of
an arrow 43. A semiconductor wafer is set as the object 21 to be
polished.
[0059] A slurry 34 is dropped in a substantially central position
on the polishing cloth 10 from a slurry supply pipe 33, and
diffused in the polishing cloth 10 toward the periphery by the
centrifugal force. The slurry 34 is once stored as it is spread
over the entire region of the polishing cloth 10.
[0060] A top ring head 22 as a polishing member rotates the
semiconductor wafer as the object 21 in the direction of an arrow
42 while pressing the wafer against the polishing cloth 10. Also, a
dressing head 32 opposes the top ring head 22 on the other side of
the central position of the turntable 31, and rotates as indicated
by an arrow 41 to dress the polishing cloth 10.
[0061] In the first embodiment, when pushed by the top ring head
22, the slurry 34 once stored in the polishing cloth 10 oozes out
toward the upper surface in FIG. 3 and is supplied between the
polishing cloth 10 and object 21.
[0062] Consequently, unlike in any conventional apparatus, it is
possible to evenly supply the slurry to the surface in contact with
the object 21 without wasting it by scattering it on the polishing
cloth 10. Also, even when the retainer ring is pressed by a high
pressure by using the head shown in FIG. 9, the slurry can be
reliably supplied to the surface in contact with the object 21.
[0063] FIG. 4 shows the polishing speed and erosion as functions of
the flow rate of slurry when the polishing apparatus according to
the embodiment of the present invention is used. Unlike in the
conventional apparatus shown in FIG. 13, both the polishing speed
and erosion are maintained substantially constant regardless of the
slurry flow rate.
[0064] Accordingly, this embodiment can reduce the cost by reducing
the use amount of slurry with a simple arrangement without
deteriorating the process performance.
[0065] Especially in a semiconductor wafer CMP process, very many
additives are contained in a slurry in order to improve the
polishing performance. Since this makes the slurry expensive, the
cost can be largely reduced by reducing the use amount of
slurry.
[0066] In order for the slurry to rapidly diffuse toward the
periphery after it is dropped directly on the second layer 12 of
the polishing cloth 10, the first layer 11 may also be removed in
the shape of a circle, as shown in FIG. 1, immediately below the
slurry supply pipe, i.e., in a central region 13a of the polishing
cloth 10.
[0067] In the first layer 11 of the polishing cloth 10, fine holes
having a diameter of, e.g., 10 .mu.m to 10 mm evenly distribute at
a density of 1 to 1,000 holes/cm.sup.2. The first layer 11 is more
desirably formed by a porous material having the linear through
holes 13 as shown in FIG. 1.
[0068] This shape can be realized by molding a porous material such
as a polymer-based material into fibers or a honeycomb shape, and
forming the through holes 13 substantially parallel to each
other.
[0069] Also, the second layer 12 can be obtained by molding, e.g.,
a generally used hard foamed polyurethane resin, such as a
polymer-based material having open cells whose diameter is, e.g.,
10 to 500 .mu.m. However, the material is not limited to this
material, and any material which can store the slurry and discharge
it when pressed can be used. Examples are polystyrene-based and
silicone-based polymers.
[0070] A method of forming a copper damascene interconnection will
be explained below as a semiconductor device fabrication method
using the polishing apparatus according to the first
embodiment.
[0071] As shown in FIG. 5, an element (not shown) is formed by
patterning in a surface portion of a semiconductor substrate 51. An
interlayer insulating film 52 having a film thickness of, e.g.,
about 3,000 .ANG. is formed on the surface of the semiconductor
substrate 51. A recess 55 which is at least one of a trench and
hole is formed in the surface of the interlayer insulating film
52.
[0072] On the entire surface including the inner surfaces of the
recess 55, a Ta/TaN layer 53 having a film thickness of, e.g.,
about 300 .ANG. is formed as a liner by sputtering.
[0073] In addition, a copper film 54 having a film thickness of,
e.g., about 7,000 .ANG. is deposited by sputtering and plating so
as to cover the entire surface.
[0074] As shown in FIG. 6, of the copper film 54 and Ta/TaN layer
53, unnecessary portions except for the portions buried in the
recess 55 are removed by CMP. The polishing apparatus according to
the first embodiment described above is used in this CMP
process.
[0075] The polishing conditions can be set, for example, as
follows.
[0076] Two types of slurries A and B presented below are supplied
onto the polishing cloth at a flow rate of 50 cc/min each.
[0077] Slurry A: Mixture of CMS7401+CMS7452 (manufactured by JSR
(registered trademark))
[0078] Slurry B: BTS-12 (manufactured by HIROTA CHEMICAL INDUSTRY
(registered trademark))
[0079] The polishing load is 400 g/cm.sup.2, and the carrier/table
rotational speeds are 100/100 rpm.
[0080] By performing the CMP process by using the polishing
apparatus according to the first embodiment, good polishing
characteristics can be obtained by using a minimum necessary
slurry.
(2) SECOND EMBODIMENT
[0081] The polishing cloth 10 used in the polishing apparatus
according to the first embodiment described above has a two-layered
structure having the first and second layers 11 and 12.
[0082] By contrast, in a polishing apparatus according to the
second embodiment, the polishing cloth has an integrated structure
such as polishing cloth 10a shown in FIG. 7. The overall
arrangement of the apparatus except for this polishing cloth is the
same as the first embodiment, so a detailed explanation thereof
will be omitted.
[0083] In the polishing cloth 10a, a slurry dropped on the surface
of the polishing cloth 10a enters the polishing cloth 10a in the
direction of an arrow 14. This slurry is diffused toward the
periphery as indicated by arrows 15 by the centrifugal force of the
rotation of a turntable, and once stored.
[0084] When the polishing cloth 10a is pressed in the direction of
an arrow 23 by a polishing member 22, the slurry oozes out in the
direction of arrows 16, and is discharged to the surface of an
object 21 to be polished.
[0085] Even when the polishing apparatus of the second embodiment
using the polishing cloth 10a as described above is used, as in the
first embodiment, the slurry is once stored in the whole of the
polishing cloth 10a by permeation, and then evenly supplied to the
surface of the object 21 to be polished.
[0086] In addition, according to the second embodiment, even when
the head shown in FIG. 9 is used, since the slurry is uniformly
supplied to that surface of the object to be polished, which is in
contact with the polishing cloth, the slurry is reliably supplied
to this surface irrespective of the pressure acting on the retainer
ring.
[0087] A method of performing the CMP process shown in FIG. 6 by
using the polishing apparatus according to the second embodiment
will be explained below.
[0088] The polishing conditions can be set, for example, as
follows.
[0089] A slurry C presented below is supplied onto the polishing
cloth at a flow rate of 300 cc/min.
[0090] Slurry C: CMS8301 (manufactured by JSR (registered
trademark))
[0091] The polishing load is 240 g/cm.sup.2, and the carrier/table
rotational speeds are 50/51 rpm.
[0092] In the second embodiment, as in the first embodiment
described previously, a slurry is once stored in the whole of the
polishing cloth, and then evenly supplied to the surface to be
polished of the semiconductor substrate. Since the slurry is
reliably supplied to the surface to be polished, good
characteristics can be obtained.
[0093] As described above, the polishing apparatuses, polishing
methods, and semiconductor device fabrication methods of the first
and second embodiments make it possible to reduce the cost by
reducing the slurry use amount without deteriorating the process
performance.
[0094] Each of the above embodiments is merely an example, and
hence does not limit the present invention. That is, these
embodiments can be variously modified within the technical scope of
the present invention.
[0095] For example, in the above embodiments, a copper film is used
as a conductive film to be polished in the CMP process. However, it
is also possible to use a film containing at least aluminum,
tungsten, titanium, niobium, tantalum, silver, vanadium, ruthenium,
platinum, silicon, or an oxide, nitride, boride, or alloy of any of
these materials.
* * * * *