U.S. patent application number 10/557608 was filed with the patent office on 2006-12-28 for removing agent composition and removing/cleaning method using same.
This patent application is currently assigned to KAO CORPORATION. Invention is credited to Yasuhiro Dpo, Atsushi Tamura.
Application Number | 20060293199 10/557608 |
Document ID | / |
Family ID | 33514808 |
Filed Date | 2006-12-28 |
United States Patent
Application |
20060293199 |
Kind Code |
A1 |
Tamura; Atsushi ; et
al. |
December 28, 2006 |
Removing agent composition and removing/cleaning method using
same
Abstract
The present invention relates to a removal cleaning method for a
semiconductor substrate or a semiconductor device with metal
wirings by using a remover composition, wherein the remover
composition contains a dissolution agent having an alumina
dissolution amount as measured according to the standard test (A-1)
of 10 ppm or more, and an inhibitor having an aluminum etching
amount as measured according to the standard test (B-1) of 7 nm or
less, and the remover composition substantially does not contain a
fluorine-containing compound; a method of producing a semiconductor
substrate or a semiconductor device, including the step involving
the removal cleaning method; and a remover composition containing a
specified acid, and a specified inorganic acid salt and/or organic
acid salt. The removal cleaning method and the remover composition
of the present invention can be suitably used for producing even
higher-speed, even more highly integrated and high quality
electronic parts such as LCDs, memories and CPUs, particularly for
cleaning a semiconductor substrate or a semiconductor device in
which a wiring material containing aluminum and/or titanium is
used.
Inventors: |
Tamura; Atsushi;
(Wakayama-shi, JP) ; Dpo; Yasuhiro; (Wakayama-shi,
JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
KAO CORPORATION
14-10, NIHONBASHI KAYABACHO 1-CHOME CHUO-KU
TOKYO
JP
103-8210
|
Family ID: |
33514808 |
Appl. No.: |
10/557608 |
Filed: |
June 4, 2004 |
PCT Filed: |
June 4, 2004 |
PCT NO: |
PCT/JP04/08162 |
371 Date: |
November 22, 2005 |
Current U.S.
Class: |
510/175 |
Current CPC
Class: |
H01L 21/02071 20130101;
H01L 21/02063 20130101 |
Class at
Publication: |
510/175 |
International
Class: |
C11D 7/32 20060101
C11D007/32 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 4, 2003 |
JP |
2003-159896 |
Aug 8, 2003 |
JP |
2003-290711 |
Nov 14, 2003 |
JP |
2003-385788 |
Nov 14, 2003 |
JP |
2003-385795 |
Claims
1. A removal cleaning method for a semiconductor substrate or a
semiconductor device with metal wirings by using a remover
composition, wherein the remover composition comprises a
dissolution agent having an alumina dissolution amount as measured
according to the standard test (A-1) of 10 ppm or more, and an
inhibitor having an aluminum etching amount as measured according
to the standard test (B-1) of 7 nm or less, and the remover
composition substantially does not contain a fluorine-containing
compound.
2. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the dissolution
agent is an acid.
3. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the inhibitor is
an inorganic acid salt and/or an organic acid salt.
4. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the inhibitor is
one or more salts selected from the group consisting of
carboxylates, sulfates, sulfonates, phosphonates, nitrates,
hydrochlorides and borates.
5. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein a weight ratio
of the dissolution agent to the inhibitor (dissolution
agent/inhibitor) is 2/1 to 1/30.
6. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the remover
composition comprises 50% by weight or more of water and has a pH
of 1 to 10.
7. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the metal
wirings comprise aluminum wirings having a wiring width of 180 nm
or less.
8. A removal cleaning method for a semiconductor substrate or a
semiconductor device with metal wirings having a wiring width of
180 nm or less by using a remover composition, wherein the remover
composition comprises a dissolution agent having an alumina
dissolution amount as measured according to the standard test (A-1)
of 10 ppm or more, and an inhibitor having an aluminum etching
amount as measured according to the standard test (B-1) of 7 nm or
less.
9. The removal cleaning method for a semiconductor substrate or a
semiconductor device according to claim 1, wherein the metal
wirings are metal wirings comprising one or more metals selected
from the group consisting of aluminum, copper, tungsten and
titanium.
10. A method of producing a semiconductor substrate or a
semiconductor device, comprising the step involving the removal
cleaning method for a semiconductor substrate or a semiconductor
device as defined in claim 1.
11. A remover composition comprising an acid, and an inorganic acid
salt and/or an organic acid salt, wherein the acid, and the
inorganic acid salt and/or the organic acid salt are any one of the
following (i) to (v): (i) the acid is
1-hydroxyethylidene-1,1-diphosphonic acid, and the inorganic acid
salt and/or the organic acid salt is one or more salts selected
from the group consisting of carboxylates, sulfates, sulfonates,
phosphonates, nitrates, hydrochlorides and borates; (ii) the acid
is sulfuric acid, and the inorganic acid salt is a sulfate and/or a
nitrite; (iii) the acid is oxalic acid, and the inorganic acid salt
is a phosphonate; (iv) the acid comprises sulfuric acid and oxalic
acid, and the inorganic acid salt is a sulfate; and (v) the acid
comprises 1-hydroxyethylidene-1,1-diphosphonic acid and oxalic
acid, and the inorganic acid salt is a sulfate.
12. A remover composition, comprising a) water, and b) a compound
having a solubility (25.degree. C.) in water of 10 g or more/100 g
of water, wherein the content of the water a) is 50 to 99.8% by
weight, and the content of the compound b) is 90% by weight or more
of the portion of the remover composition excluding the water a),
and the remover composition has an aluminum oxide dissolution
amount as measured according to the standard test (A-2) of 10 ppm
or more, and an aluminum etching amount as measured according to
the standard test (B-2) of 7 nm or less.
13. The remover composition according to claim 12, wherein the
remover composition comprises an acid, and an inorganic acid salt
and/or an organic acid salt as the compound b).
14. The remover composition according to claim 13, wherein the acid
is contained in an amount of 0.01 to 5% by weight, and the
inorganic acid salt and/or the organic acid salt is contained in an
amount of 0.2 to 40% by weight.
15. The remover composition according to claim 12, wherein the
remover composition has a pH of 1 to 10.
16. A method of cleaning a semiconductor by using the remover
composition as defined in claim 12.
17. The method of cleaning a semiconductor according to claim 16,
wherein the semiconductor is a semiconductor with aluminum wirings
having a wiring width of 180 nm or less.
18. A method of producing a semiconductor, comprising the step of
cleaning using the cleaning method as defined in claim 16.
19. A water-based remover composition, comprising an aluminum oxide
dissolution agent and an aluminum corrosion inhibitor, wherein the
water-based remover composition has: 1) a water content of 50% by
weight or more; 2) an aluminum oxide dissolution amount as measured
according to the standard test (A-2) of 10 ppm or more; 3) an
aluminum etching amount as measured according to the standard test
(B-2) of 7 nm or less; and provides 4) a pH change before and after
the standard test (A-2) of 0.5 or less.
20. The remover composition according to claim 19, wherein the
aluminum oxide dissolution agent is an acid, and the aluminum
corrosion inhibitor is an inorganic acid salt and/or an organic
acid salt.
21. The remover composition according to claim 19, wherein the
remover composition has a pH of 1 to 10.
22. A method of continuous cleaning of a semiconductor, comprising
the step of cleaning at 60.degree. C. or lower, by using the
remover composition as defined in claim 19.
23. The method of continuous cleaning of a semiconductor according
to claim 22, wherein a semiconductor substrate or a semiconductor
device with aluminum wirings having a wiring width of 180 nm or
less is used.
24. A method of producing a semiconductor, comprising the step of
cleaning using the method of continuous as defined in claim 22.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a removal cleaning method,
in which "deposition" (oxide products originated from metal
materials, and the like), which remain after removing by ashing the
resist used in a step of forming a semiconductor device on a
semiconductor substrate such as a silicon wafer, are removed from
the semiconductor substrate or the semiconductor device with metal
wirings; a method of producing a semiconductor substrate or a
semiconductor device by using the removal cleaning method; and a
remover composition.
[0002] The present invention also relates to a remover composition
for removing deposition which remain after removing by ashing the
resist used in a step of forming a semiconductor device on a
semiconductor substrate such as a silicon wafer; a method of
cleaning a semiconductor by using the remover composition; and a
method of producing a semiconductor substrate or a semiconductor
device, including the step of cleaning by removing deposition by
using the remover composition.
BACKGROUND ART
[0003] In the production of semiconductor devices, a thin film is
formed by using a method such as sputtering, and a predetermined
pattern is formed on the thin film with a resist by lithography.
Based on this pattern as an etching resist, the underlying thin
film is selectively removed by etching, followed by a step of
removing the resist by ashing. Thereafter, a step of removing the
remaining deposition by using a remover is required.
[0004] As removers for conventional semiconductor devices with
aluminum wirings, various remover compositions have been proposed,
and removers in which a fluorine-containing compound is used, and
removers in which an amine represented by hydroxylamine is used,
have been mainly used.
[0005] However, with increasing demands for higher-speed and more
highly integrated semiconductor devices, the wirings are finer and
the wiring width is narrower, so that it has been an essential
requirement to prevent occurrence of wiring corrosion (etching) by
a remover during cleaning.
[0006] JP-A-Hei-10-55993 discloses, as a cleaning agent which does
not corrode metal film, a remover composition composed of a
quaternary ammonium salt or an organic ammonium carboxylate,
ammonium fluoride, a water-soluble organic solvent, and an
inorganic acid or an organic acid. This remover composition is
effective for use in conventional devices with wirings of a wide
wiring width. However, this remover composition has a problem with
use in devices with wirings of a narrow wiring width, because
ammonium fluoride is highly corrosive to aluminum wirings.
[0007] Also, JP 2000-267302 A discloses a remover composition
containing a combination of an organic acid and a surfactant (an
organic sulfate, a sulfonate, a fatty acid salt, and the like), but
this remover composition has low deposition-removing power. When
the amount of the organic acid is increased to improve deposition
eliminability, corrosion of aluminum wirings occurs, so that a
sufficient effect is not obtained. Therefore, to date, no remover
composition has been obtained which satisfies both of deposition
eliminability and low corrosiveness to aluminum wirings, which are
required for devices with wirings of a narrow wiring width.
[0008] On the other hand, when via holes which connect wirings are
formed, there is also an increasing tendency that a large quantity
of titanium-based deposition is adhered, due to narrower wiring
width, during etching of the titanium or titanium nitride on the
bottom of the via holes. Further, these titanium-based depositions
are solidified in the subsequent ashing step, which makes the
removal cleaning of deposition very difficult. Therefore, a
sufficient removability is not obtained even when a
fluorine-containing compound-based remover or an amine-based
remover is used for the removing.
[0009] In view of the above problem, there are proposed a remover
containing hydrogen peroxide, a quaternary ammonium salt and a
hydrogen peroxide compound (JP 2002-202618 A), a remover which
contains hydrogen peroxide, a quaternary ammonium salt and an
anticorrosive and is used under alkaline conditions (JP 2003-5383
A), and the like. However, these removers require removal cleaning
to be done under high-temperature conditions, and the removability
of titanium-based deposition is still insufficient. Consequently,
these removers have not solved the problem.
[0010] Further, in an attempt to clean by using an aqueous cleaning
agent containing a combination of an organic acid and water or a
combination of an organic acid, a water-soluble solvent and water,
as described in JP-A-Hei-10-256210 and JP-A-Hei-11-316464, there
arises problems such as deposition eliminability is decreased and
the anticorrosiveness for aluminum wirings is deteriorated, as
compared with the initial cleaning stage, as a continuous cleaning
is proceeded. Therefore, practically, a continuous cleaning cannot
be performed for a long period of time, and the remover, when used,
needs to be replaced with a new one in a short period of time.
[0011] On the other hand, in a system of phosphoric acid and
ammonium phosphate as described in JP 2000-232063 A, and a system
of ammonium fluoride, an acid and an organic ammonium carboxylate
as described in JP-A-Hei-10-55993, though a change in cleaning
performance with continuous cleaning is small, deposition
dissolution and anticorrosiveness for aluminum wirings, which are
the basic properties, cannot be attained sufficiently at the same
time from the initial stage of cleaning.
[0012] In addition, each of JP-A-Hei-9-279189 and JP 2001-26890 A
discloses an aqueous cleaning agent used for cleaning
semiconductors. However, both of the cleaning agents insufficiently
satisfy deposition eliminability and anticorrosiveness for aluminum
wirings at the same time.
[0013] Particularly, it is difficult to use these conventionally
known aqueous removers in semiconductor substrates and
semiconductor devices with wirings having a narrow wiring width of
180 nm or less, which is required for higher-speed and more highly
integrated semiconductors in the future.
[0014] Also, when conventionally known aqueous removers are used in
an open-topped cleaning vessel for a long period of time, or used
in a circulation system, there is a problem that semiconductor
substrates and the like are contaminated over time. In a practical
situation, a remover is replaced with a new one in a short period
of time to deal with this problem.
SUMMARY OF THE INVENTION
[0015] Specifically, the gist of the present invention relates to:
[0016] [1] a removal cleaning method for a semiconductor substrate
or a semiconductor device with metal wirings by using a remover
composition, wherein the remover composition contains a dissolution
agent having an alumina dissolution amount as measured according to
the standard test (A-1) of 10 ppm or more, and an inhibitor having
an aluminum etching amount as measured according to the standard
test (B-1) of 7 nm or less, and the remover composition
substantially does not contain a fluorine-containing compound;
[0017] [2] the removal cleaning method for a semiconductor
substrate or a semiconductor device of the above [1], wherein the
dissolution agent is an acid; [0018] [3] the removal cleaning
method for a semiconductor substrate or a semiconductor device of
the above [1] or [2], wherein the inhibitor is an inorganic acid
salt and/or an organic acid salt; [0019] [4] the removal cleaning
method for a semiconductor substrate or a semiconductor device of
any one of the above [1] to [3], wherein the inhibitor is one or
more salts selected from the group consisting of carboxylates,
sulfates, sulfonates, phosphonates, nitrates, hydrochlorides and
borates; [0020] [5] the removal cleaning method for a semiconductor
substrate or a semiconductor device of any one of the above [1] to
[4], wherein a weight ratio of the dissolution agent to the
inhibitor (dissolution agent/inhibitor) is 2/1 to 1/30; [0021] [6]
the removal cleaning method for a semiconductor substrate or a
semiconductor device of any one of the above [1] to [5], wherein
the remover composition contains 50% by weight or more of water and
has a pH of 1 to 10; [0022] [7] the removal cleaning method for a
semiconductor substrate or a semiconductor device of any one of the
above [1] to [6], wherein the metal wirings include aluminum
wirings having a wiring width of 180 nm or less; [0023] [8] a
removal cleaning method for a semiconductor substrate or a
semiconductor device with metal wirings having a wiring width of
180 nm or less by using a remover composition, wherein the remover
composition contains a dissolution agent having an alumina
dissolution amount as measured according to the standard test (A-1)
of 10 ppm or more, and an inhibitor having an aluminum etching
amount as measured according to the standard test (B-1) of 7 nm or
less; [0024] [9] the removal cleaning method for a semiconductor
substrate or a semiconductor device of any one of the above [1] to
[8], wherein the metal wirings are metal wirings containing one or
more metals selected from the group consisting of aluminum, copper,
tungsten and titanium; [0025] [10] a method of producing a
semiconductor substrate or a semiconductor device, including the
step involving the removal cleaning method for a semiconductor
substrate or a semiconductor device as defined in any one of the
above [1] to [9]; [0026] [11] a remover composition containing an
acid, and an inorganic acid salt and/or an organic acid salt,
wherein the acid, and the inorganic acid salt and/or the organic
acid salt are any one of the following (i) to (v): [0027] (i) the
acid is 1-hydroxyethylidene-1,1-diphosphonic acid, and the
inorganic acid salt and/or the organic acid salt is one or more
salts selected from the group consisting of carboxylates, sulfates,
sulfonates, phosphonates, nitrates, hydrochlorides and borates;
[0028] (ii) the acid is sulfuric acid, and the inorganic acid salt
is a sulfate and/or a nitrite; [0029] (iii) the acid is oxalic
acid, and the inorganic acid salt is a phosphonate; [0030] (iv) the
acid comprises sulfuric acid and oxalic acid, and the inorganic
acid salt is a sulfate; and [0031] (v) the acid comprises
1-hydroxyethylidene-1,1-diphosphonic acid and oxalic acid, and the
inorganic acid salt is a sulfate; [0032] [12] a remover
composition, containing a) water, and b) a compound having a
solubility (25.degree. C.) in water of 10 g or more/100 g of water,
wherein the content of the water a) is 50 to 99.8% by weight, and
the content of the compound b) is 90% by weight or more of the
portion of the remover composition excluding the water a), and the
remover composition has an aluminum oxide dissolution amount as
measured according to the standard test (A-2) of 10 ppm or more,
and an aluminum etching amount as measured according to the
standard test (B-2) of 7 nm or less; [0033] [13] the remover
composition of the above [12], wherein the remover composition
contains an acid, and an inorganic acid salt and/or an organic acid
salt as the compound b); [0034] [14] the remover composition of the
above [13], wherein the acid is contained in an amount of 0.01 to
5% by weight, and the inorganic acid salt and/or the organic acid
salt is contained in an amount of 0.2 to 40% by weight; [0035] [15]
the remover composition of any one of the above [12] to [14],
wherein the remover composition has a pH of 1 to 10; [0036] [16] a
method of cleaning a semiconductor by using the remover composition
as defined in any one of the above [12] to [15]; [0037] [17] the
method of cleaning a semiconductor of the above [16], wherein the
semiconductor is a semiconductor with aluminum wirings having a
wiring width of 180 nm or less; [0038] [18] a method of producing a
semiconductor, including the step of cleaning using the cleaning
method as defined in the above [16] or [17]; [0039] [19] a
water-based remover composition, containing an aluminum oxide
dissolution agent and an aluminum corrosion inhibitor, wherein the
water-based remover composition has: 1) a water content of 50% by
weight or more; 2) an aluminum oxide dissolution amount as measured
according to the standard test (A-2) of 10 ppm or more; 3) an
aluminum etching amount as measured according to the standard test
(B-2) of 7 nm or less; and provides 4) a pH change before and after
the standard test (A-2) of 0.5 or less; [0040] [20] the remover
composition of the above [19], wherein the aluminum oxide
dissolution agent is an acid, and the aluminum corrosion inhibitor
is an inorganic acid salt and/or an organic acid salt; [0041] [21]
the remover composition of the above [19] or [20], wherein the
remover composition has a pH of 1 to 10; [0042] [22] a method of
continuous cleaning of a semiconductor, including the step of
cleaning at 60.degree. C. or lower, by using the remover
composition as defined in any one of the above [19] to [21]; [0043]
[23] the method of continuous cleaning of a semiconductor of the
above [22], wherein a semiconductor substrate or a semiconductor
device with aluminum wirings having a wiring width of 180 nm or
less is used; and [0044] [24] a method of producing a
semiconductor, including the step of cleaning using the method of
continuous cleaning as defined in the above [22] or [23].
[0045] These objects of the present invention and other objects
will be apparent from the following description.
DETAILED DESCRIPTION OF THE INVENTION
[0046] A first embodiment of the present invention relates to a
removal cleaning method for a semiconductor substrate or a
semiconductor device with metal wirings, wherein deposition
originated from aluminum wirings produced after ashing and
titanium-based deposition produced during via hole formation can be
removed effectively, and corrosion of aluminum wiring materials as
well as titanium, titanium nitride and the like on the bottom the
holes can be drastically suppressed; a method of producing a
semiconductor substrate or a semiconductor device by using the
removal cleaning method; and a remover composition which is
excellent in deposition eliminability and capable of drastically
suppressing corrosion of wirings. Particularly, this embodiment
relates to a removal cleaning method for a semiconductor substrate
or a semiconductor device, which is suitable for cleaning
semiconductor devices with aluminum wirings having a narrow wiring
width of 180 nm or less; a method of producing a semiconductor
substrate or a semiconductor device by using the removal cleaning
method; and a remover composition which is excellent in deposition
eliminability and capable of drastically suppressing corrosion of
wirings.
[0047] Also, a second embodiment of the present invention relates
to a water-based remover composition which can prevent
semiconductors from contamination, without corrosion of aluminum
wiring materials as well as titanium, titanium nitride and the like
on the bottom of the holes, during cleaning by removing deposition
originated from aluminum wirings produced after ashing and
titanium-based deposition produced during via hole formation; a
method of cleaning by using the remover composition; and a method
of producing a semiconductor substrate or a semiconductor device,
including the step of cleaning by using the remover
composition.
[0048] Particularly, this embodiment relates to a method of
cleaning, with preventing contamination, a semiconductor substrate
or a semiconductor device with aluminum wirings having a narrow
wiring width of 180 nm or less, which are easily affected by
contaminants; and a method of producing a semiconductor substrate
or a semiconductor device, including the step of cleaning with
preventing contamination.
[0049] Also, a third embodiment of the present invention relates to
a remover composition which can be used continuously for a long
period of time, without changing the initial performance, without
corrosion of aluminum wiring materials as well as titanium,
titanium nitride and the like on the bottom of the holes, during
cleaning by removing deposition originated from aluminum wirings
produced after ashing and titanium-based deposition produced during
via hole formation using a remover composition; a method of
continuous cleaning of a semiconductor such as a semiconductor
substrate or a semiconductor device by using the remover
composition; and a method of producing a semiconductor, including
the step of cleaning by using the method of continuous
cleaning.
[0050] Particularly, this embodiment relates to a remover
composition which works effectively on a semiconductor with
aluminum wirings having a narrow wiring width of 180 nm or less,
which require high cleaning ability; a related method of continuous
cleaning; and a method of producing a semiconductor.
[0051] Incidentally, all of the present inventions, as represented
by these embodiments 1 to 3, are different from cleaning agents for
eliminating particles produced during polishing silicon wafer
substrates, and the like, and for eliminating particles and metal
impurities after polishing embedded metal which connects wirings to
one another (CMP polishing).
Embodiment 1
[0052] A first embodiment of the present invention is a removal
cleaning method for a semiconductor substrate or a semiconductor
device with metal wirings by using a remover composition, wherein
the remover composition contains a dissolution agent having an
alumina dissolution amount as measured according to the standard
test (A-1) of 10 ppm or more and an inhibitor having an aluminum
etching amount as measured according to the standard test (B-1) of
7 nm or less, and the remover composition substantially does not
contain a fluorine-containing compound.
1. Remover Composition
[0053] The present inventors have found that it is highly effective
to use a remover composition containing a dissolution agent having
an alumina dissolution amount more than a specified value and an
inhibitor having an aluminum etching amount less than a specified
value, in order to improve deposition eliminability after ashing of
aluminum wirings, while suppressing corrosion of aluminum wirings.
Specifically, Embodiment 1 has a feature that the remover
composition to be used contains a dissolution agent having an
alumina dissolution amount as measured according to the standard
test (A-1) of 10 ppm or more and an inhibitor having an aluminum
etching amount as measured according to the standard test (B-1) of
7 nm or less. By using such a remover composition, there are
exhibited effects that an excellent removability of deposition
produced during production of semiconductor devices is obtained and
that corrosion of materials such as wiring metals can be
prevented.
[0054] Also, the remover composition has another feature that the
composition substantially does not contain a fluorine-containing
compound and, by this feature, the composition has an advantage of
causing no problems with anticorrosiveness for wirings and waste
water treatment.
[0055] Particularly, in a water-based remover composition
containing, as effective components, a fluorine-containing
compound, of which aqueous solution (0.2%) has an aluminum etching
amount exceeding 50 nm, such as hydrogen fluoride, ammonium
fluoride or an amine salt of hydrofluoric acid, when an aluminum
etching test is carried out in the same manner as in the standard
test (B-1), metal corrosion tends to occur more markedly with
increase in the content of water. Therefore, in Embodiment 1,
"substantially not containing a fluorine-containing compound"
specifically means that the content of the fluorine-containing
compound in the remover composition used in Embodiment 1 is 0.1% by
weight or less, preferably 0.05% by weight or less, more preferably
0.01% by weight or less, and even more preferably 0.001% by weight
or less. Especially preferably, no fluorine-containing compound is
contained.
[0056] Incidentally, as the remover composition for a removal
cleaning for a semiconductor substrate or a semiconductor device
with metal wirings having a wiring width of 180 nm or less by using
a remover composition, a remover composition has a sufficient
effect which just contains a dissolution agent having an alumina
dissolution amount as measured according to the standard test
(A-1), described below, of 10 ppm or more and an inhibitor having
an aluminum etching amount as measured according to the standard
test (B-1) of 7 nm or less. Therefore, the present invention also
relates a removal cleaning method for a semiconductor substrate or
a semiconductor device with metal wirings having a wiring width of
180 nm or less by using a remover composition, wherein the remover
composition contains a dissolution agent having an alumina
dissolution amount as measured according to the standard test (A-1)
of 10 ppm or more and an inhibitor having an aluminum etching
amount as measured according to the standard test (B-1) of 7 nm or
less.
[0057] The procedures of the standard test (A-1) and the standard
test (B-1) will be described below.
[0058] <Standard Test (A-1)> [0059] 1) Twenty grains of a 0.2
wt % aqueous solution of a dissolution agent is placed in a 100-ml
polyethylene container, and kept at a constant temperature in a
thermostatic chamber at 40.degree. C. [0060] 2) Next, 0.1 g of an
alumina powder (trade name: "WA-10000," manufactured by Fujimi
Corporation; average particle size: 0.5 .mu.m) is added to the
solution, and sufficiently stirred for 30 minutes. [0061] 3) Ten
grams of an aliquot of the supernatant is placed in a centrifuging
tube, and allowed to separate using a centrifuge (trade name:
"himac CP56G," manufactured by Hitachi, Ltd.) under conditions at
20,000 r/min for 15 minutes. The light emission intensity from
aluminum is determined for the resulting supernatant using an ICP
emission analyzer (trade name: "JY238," manufactured by Horiba
Ltd.). [0062] 4) The alumina dissolution amount is determined from
a calibration curve made using an aqueous solution of aluminum of
known concentrations.
[0063] Incidentally, from the viewpoint of performing the
measurement more excellently, the supernatant is diluted ten-fold
with ultrapure water for measuring the light emission intensity
from aluminum in 3). When the concentration is over the range of
the calibration curve (0 to 2 ppm), the diluted solution is again
diluted ten-fold for the measurement. Also in 4), an aqueous
solution of aluminum (1,000 ppm) is diluted 10,000-fold (0.1 ppm)
and 500-fold (2.0 ppm), respectively, with ultrapure water, and the
resulting dilutions are subjected to an atomic absorption analysis
to make a calibration curve (three-point calibration).
[0064] <Standard Test (B-1)> [0065] 1) A test piece is
prepared by cutting out a 3-cm square piece from a substrate having
an aluminum sputtering layer (thickness: about 500 nm) formed on a
silicon wafer by a CVD method. [0066] 2) A test aqueous solution is
prepared in which the concentration of
1-hydroxyethylidene-1,1-diphosphonic acid ("Dequest 2010R,"
manufactured by Sorcia Japan Kabushiki Kaisha) is 0.2% by weight
and the concentration of an inhibitor is 4.0% by weight. [0067] 3)
The test piece is subjected to pre-cleaning by immersing in a 0.1
wt % aqueous HF solution at room temperature for 30 seconds,
rinsing with water, and drying by blowing nitrogen. The fluorescent
X-ray intensity from aluminum is measured for the resulting test
piece, using a fluorescent X-ray measuring device ("ZSX100e,"
manufactured by Rigaku Denki Kogyo Co., Ltd.) (measurement of film
thickness before immersing in the test aqueous solution). [0068] 4)
Thereafter, the test piece is immersed in 20 g of the test aqueous
solution kept at a constant temperature at 40.degree. C. for 30
minutes, rinsed with ion exchange water and dried by blowing
nitrogen. Then, the fluorescent X-ray intensity from aluminum is
measured for the resulting test piece on the same position as that
measured before immersing, using a fluorescent X-ray measuring
device (measurement of film thickness after immersing in the test
aqueous solution). [0069] 5) The film thicknesses before and after
immersing in the test aqueous solution are calculated from the
calibration curve made previously for aluminum sputtering film of
known film thicknesses using a fluorescent X-ray measuring
device.
[0070] The dissolution agent contained in the remover composition
used in Embodiment 1 is one having an alumina dissolution amount as
measured according to the above-mentioned standard test (A-1) of 10
ppm or more. It is desirable that the alumina dissolution amount is
preferably 12 ppm or more, and more preferably 15 ppm or more, from
the viewpoint of enhancing deposition removability after
ashing.
[0071] The dissolution agent is not particularly limited, as long
as it can satisfy the above requirement. It is desirable to use an
acid as the dissolution agent from the viewpoint of attaining
deposition removability and anticorrosiveness for wirings at the
same time. Among acids, in particular, one or more acids selected
from the group consisting of inorganic acids such as phosphonic
acid, sulfuric acid, nitric acid, phosphoric acid and hydrochloric
acid, and organic acids such as organic phosphonic acid, organic
sulfuric acid, carboxylic acid and organic sulfonic acid are
desirably used. Specifically, sulfuric acid, hydrochloric acid,
nitric acid, methanesulfonic acid, sulfosuccinic acid, oxalic acid
and 1-hydroxyethylidene-1,1-diphosphonic acid are preferable and,
in particular, sulfuric acid, oxalic acid and
1-hydroxyethylidene-1,1-diphosphonic acid are preferable.
[0072] The content of the dissolution agent is preferably 0.01 to
5% by weight, more preferably 0.01 to 3% by weight, even more
preferably 0.01 to 2% by weight, and especially preferably 0.05 to
2% by weight, from the viewpoint of attaining deposition
removability and anticorrosiveness for wirings at the same
time.
[0073] Also, the inhibitor contained in the remover composition
used in Embodiment 1 has an aluminum etching amount as measured
according to the standard test (B-1) of 7 nm or less. It is
desirable that the aluminum etching amount is preferably 5 nm or
less, and more preferably 3 nm or less, from the viewpoint of
preventing corrosion of aluminum wirings. The inhibitor in the
present invention is not particularly limited, as long as it can
satisfy the above requirement. It is desirable to use an inorganic
acid salt and/or an organic acid salt as the inhibitor. Among the
salts, in particular, one or more salts selected from the group
consisting of carboxylates, sulfates, sulfonates, phosphonates,
nitrates, hydrochlorides and borates are desirable. Specifically
included are ammonium acetate, ammonium citrate, ammonium oxalate,
ammonium sulfosuccinate, ammonium sulfate, ammonium
methanesulfonate, ammonium phosphonate, ammonium nitrate, ammonium
chloride, ammonium tetraborate, and the like. With regard to the
cations, these salts may be amine salts or quaternary ammonium
salts, as well as ammonium salts. The amines are not particularly
limited, as long as they are basic, and include hydroxylamines such
as hydroxylamine and diethylhydroxylamine; alkylamines such as
ethylamine, propanediamine, dibutylamine and trimethylamine;
alkanolamines such as monoethanolamine, methylethanolamine and
methyldiethanolamine; aromatic amines such as aniline and
benzylamine; and the like. The quaternary ammonium ions which form
a quaternary ammonium salt include tetramethylammonium ion,
tetraethylammonium ion, triethylmethylammonium ion,
lauryltrimethylammonium ion, benzyltrimethylammonium ion, and the
like.
[0074] Among these combinations, ammonium sulfate,
tetramethylammonium sulfate, methylethanolamine sulfate,
methyldiethanolamine sulfate and ammonium chloride are especially
preferable, and ammonium sulfate is most preferable.
[0075] The content of the inhibitor in the remover composition used
in Embodiment 1 is preferably 0.2 to 40% by weight, more preferably
0.5 to 30% by weight, even more preferably 1 to 20% by weight, and
especially preferably 5 to 10% by weight, from the viewpoint of
anticorrosiveness for metal materials such as aluminum wirings,
homogenous dissolution in water and deposition dissolubility.
[0076] The formulated weight ratio of the dissolution agent to the
inhibitor (dissolution agent/inhibitor) in Embodiment 1 is
preferably 2/1 to 1/30, more preferably 1/2 to 1/30, even more
preferably 1/4 to 1/30, and even more preferably 1/6 to 1/25, from
the viewpoint of attaining deposition removability and
anticorrosiveness for wirings at the same time.
[0077] The combination of the dissolution agent and the inhibitor
is properly selected from the dissolution agents and the inhibitors
mentioned above, without any particular limitation. For instance,
from the viewpoint of attaining deposition removability and
anticorrosiveness for wirings at the same time, it is preferable
that the dissolution agent is 1-hydroxyethylidene-1,1-diphosphonic
acid and the inhibitor is one or more salts selected from the group
consisting of carboxylates, sulfates, sulfonates, phosphonates,
nitrates, hydrochlorides and borates. Among them, preferable is a
combination of 1-hydroxyethylidene-1,1-diphosphonic acid and a
sulfate.
[0078] Also, preferred examples include a combination of sulfuric
acid and a sulfate and/or a nitrate; a combination of oxalic acid
and a phosphonate; a combination of sulfuric acid, oxalic acid and
a sulfate; a combination of 1-hydroxyethylidene-1,1-diphosphonic
acid, oxalic acid and a sulfate; and the like.
[0079] In addition, other preferred examples include a combination
of the dissolution agent selected from phosphonic acid, organic
phosphonic acid and organic sulfuric acid and the inhibitor
selected from a phosphonate, hydrochloride and borate.
[0080] Further, additional preferred examples include a combination
of the dissolution agent selected from methanesulfonic acid and
sulfosuccinic acid, and the inhibitor selected from ammonium
citrate, ammonium sulfosuccinate, ammonium sulfate, ammonium
methanesulfonate, ammonium phosphonate and ammonium chloride.
[0081] The remover composition used in Embodiment 1 contains water
in an amount of preferably 50% by weight or more, more preferably
60 to 99.7% by weight, even more preferably 70 to 99.4% by weight,
and especially preferably 90 to 99.4% by weight, from the viewpoint
of stability of the composition due to highly homogenous
dissolution of the dissolution agent, the inhibitor or the like,
operability and environmental issues such as waste water
treatment.
[0082] With respect to the pH of the above remover composition,
when the pH is 1 or more, the inhibitor becomes more effective, so
the composition is especially excellent in anticorrosiveness for
wirings. When the pH is 10 or less, the composition is excellent in
deposition removability, in particular, when the pH is 6 or less,
the composition is especially excellent in removability of
deposition originated from aluminum wirings by the dissolution
agent, while when the pH is 7 or more, the composition is
particularly excellent in removability of deposition originated
from interlayer films during via hole formation.
[0083] Therefore, the pH is preferably 1 to 10 from the viewpoint
of attaining deposition removability and anticorrosiveness for
wirings at the same time. In addition, the pH is more preferably 1
to 6, even more preferably 1 to 5, even more preferably 1 to 4, and
even more preferably 1 to 3, from the viewpoint of excellent
removability of titanium-based deposition produced during via hole
formation.
[0084] Also, the pH is preferably 6 to 10, more preferably 7 to
9.5, and especially preferably 7.5 to 9.0, from the viewpoint of
attaining removability of deposition originated from interlayer
films during via hole formation and anticorrosiveness for wirings
at the same time, and the viewpoint of excellent removability of
deposition originated from film components such as TEOS and
deposition originated from resist.
[0085] In addition, when the above remover composition contains 50%
by weight or more of water, the pH is preferably 1 to 10, and more
preferably 1 to 5, from the viewpoint of deposition removability
and anticorrosiveness for wirings.
[0086] Further, the remover composition may contain other
additives, if necessary, to an extent that the functions of the
above-mentioned deposition removability and anticorrosiveness for
wirings are not drastically deteriorated. For example, the remover
composition can contain a water-soluble solvent in order to impart
permeability and the like, and the content of the water-soluble
solvent is preferably 30% by weight or less, more preferably 20% by
weight or less, and even more preferably 10% by weight or less. In
addition, an anticorrosive agent, a surfactant, an antiseptic and
the like can be added.
[0087] The remover composition used in Embodiment 1 may be used in
any one of the steps of producing a semiconductor device or a
semiconductor substrate. Specifically, the composition can be used
in a step of producing a semiconductor device, including steps, for
example, after development of resist, after dry etching, after wet
etching and after ashing. Particularly, removability of deposition
on aluminum wirings and anticorrosiveness for aluminum wirings are
excellent. In particular, from the viewpoint of removability of
deposition, it is preferable that the remover composition is used
in the removing step after dry ashing, and the deposition
removability and anticorrosiveness for aluminum wirings are
excellent particularly in a semiconductor substrate or a
semiconductor device with aluminum wirings.
[0088] The concentration of each component in the above-mentioned
remover composition is a concentration which is preferable in its
actual use. A high concentration product of the remover composition
can be prepared and diluted prior to use. As the high concentration
product, preferable is a product comprising 20 to 40% by weight of
a sulfate, 1 to 5% by weight of
1-hydroxyethylidene-1,1-diphosphonic acid and 60 to 80% by weight
of water.
[0089] Also, the remover composition prepared in a two-component
form may be used by combining the two components to form single
component at the time of use.
[0090] The remover composition used in Embodiment 1 may be prepared
by mixing the above-mentioned dissolution agent, inhibitor and the
like in a medium by known methods.
[0091] Since the remover composition used in Embodiment 1 has both
excellent deposition removability and anticorrosiveness for
wirings, the composition can be used in removal cleaning for a
semiconductor substrate or a semiconductor device with wirings
having a wiring width as narrow as 180 nm or less, to which
conventional removers cannot be applied. In semiconductor
substrates with wirings having a wiring width of 500 nm or more,
even if wiring metal corrosion during deposition elimination is not
minor, this is not likely to be problematic because the electric
resistance will not be increased easily due to the wide wiring
width. However, for narrow wirings having a wiring width of 180 nm
or less, in accordance with higher-speed and more highly integrated
devices, a large amount of corrosion results in a significant
increase in electric resistance, which may cause a conductive
defect. In such a situation, the remover composition used in
Embodiment 1 can be advantageously applied particularly to a
semiconductor substrate with wirings having a narrow wiring width,
since the composition has high deposition removability and causes
highly reduced amount of wiring metal corrosion due to the effect
of the inhibitor.
2. Removal Cleaning Method for Semiconductor Substrate or
Semiconductor Device
[0092] The removal cleaning method for a semiconductor substrate or
a semiconductor device of Embodiment 1 has a feature that a
semiconductor substrate or a semiconductor device with metal
wirings is subjected to removal cleaning by using the remover
composition described above. The means for removal cleaning are not
particularly limited, and include immersing removal cleaning,
oscillation removal cleaning, single wafer removal cleaning,
removal cleaning utilizing a rotating means such as a spinner,
paddle cleaning, removal cleaning by spraying in air or a liquid,
ultrasonic removal cleaning and the like. Among them, immersing
removal cleaning and oscillation removal cleaning are suitable.
[0093] The cleaning temperature is preferably 20.degree. to
70.degree. C., more preferably in the range of 20.degree. to
60.degree. C., and even more preferably 20.degree. to 50.degree.
C., from the viewpoint of deposition dissolution, deposition
removability, anticorrosiveness for metal wiring materials, safety
and operability. Incidentally, there is no particular limitation to
the other cleaning conditions in the above-mentioned means for
removal cleaning.
[0094] In the rinsing step after cleaning with the above-mentioned
remover composition, water rinsing can be employed. Conventional
removers based on ammonium fluoride or based on an amine such as
hydroxylamine are a solvent-based remover, so that they are
difficult to be rinsed off with water. In addition, there is a
possibility of corrosion of wirings and the like occurring when
these removers are mixed with water. For that reason, there has
been generally employed a method of rinsing with a solvent such as
isopropanol. However, the remover composition used in Embodiment 1
is highly anticorrosive for wirings even under excessive water
since the composition is water-based and the composition contains
the inhibitor thereby to suppress corrosion of wirings. Therefore,
water rinsing can be employed, which provides an economical removal
cleaning method, with highly reduced environmental damage.
3. Method of Producing Semiconductor Substrate or Semiconductor
Device
[0095] The method of producing a semiconductor substrate or a
semiconductor device of Embodiment 1 has a feature that the method
includes a step of removal cleaning for a semiconductor substrate
or a semiconductor device by using the remover composition
described above. The removal cleaning method for a semiconductor
substrate or a semiconductor device, used in this producing method,
is preferably the same method as described above. The semiconductor
substrate or semiconductor device, obtained by using the above
remover composition and the above method of cleaning a
semiconductor substrate or a semiconductor device, has no remaining
deposition, with highly reduced corrosion of metal wiring
materials. Also, the composition and method can be used for removal
cleaning for a fine semiconductor substrate or a semiconductor
device with wirings having a wiring width of 180 nm or less, to
which conventional removers cannot be applied. Therefore, the
remover composition and method can be suitably used for producing
smaller and higher performance electronic parts such as LCDs,
memories and CPUs.
[0096] Incidentally, the invention of Embodiment 1 is suitable for
producing a semiconductor substrate or a semiconductor device
having wirings containing a metal such as aluminum, copper,
tungsten or titanium, and excellent in removability of aluminum-
and titanium-based deposition, so that it is particularly suitable
for producing a semiconductor substrate or a semiconductor device
in which a wiring material comprising aluminum and/or titanium is
used.
[0097] Incidentally, the wiring width of these metal wirings is
preferably 180 nm or less, and metal wirings having a wiring width
of 130 nm or less, and preferably 90 nm or less, can be effectively
cleaned.
Embodiment 2
[0098] Also, the present inventors have investigated the route of
contamination of a semiconductor substrate or a semiconductor
device (hereinafter simply referred to as a semiconductor). As a
result, it has been found that when a remover composition is used
in an open system for a long period of time or used in a
circulation system, water in the composition evaporates during the
removal cleaning, causing the dissolved solid matter to be
precipitated on the side wall of the cleaning tank, the filter, and
the like, and further spread in the atmosphere by air blowing or
the like on the clean room, which contaminates the objects to be
cleaned, including a semiconductor substrate and the like.
Therefore, the inventors have focused their attention on solubility
in water of the components of the remover composition used in the
removal cleaning step, and thus completed the invention of
Embodiment 2.
[0099] Specifically, the remover composition for semiconductor of
Embodiment 2 is a remover composition, containing a) water, and b)
a compound having a solubility (25.degree. C.) in water of 10 g or
more/100 g of water, wherein the content of the water a) is 50 to
99.8% by weight of the remover composition, and the content of the
compound b) is 90% by weight or more of the portion of the remover
composition excluding the water a), and the remover composition has
an aluminum oxide dissolution amount as measured according to the
standard test (A-2) of 10 ppm or more, and an aluminum etching
amount as measured according to the standard test (B-2) of 7 nm or
less. By using such a remover composition, generation of
precipitates from the remover composition, which occurs when water
of the medium evaporates, for instance, is suppressed in the
cleaning step. Therefore, there is exhibited an effect that
contamination of semiconductor can be prevented. Further there is
exhibited an effect that high-performance electronic parts such as
LCDs, memories and CPUs can be produced.
[0100] Particularly, the remover composition is highly effective
for a semiconductor substrate or a semiconductor device with
aluminum wirings having a narrow wiring width, of which performance
is significantly affected by only a small amount of
contamination.
[0101] In addition, there is a problem that the generation of these
precipitates results in clogging of filters in pipes and the like,
and also affects operability and the like. The remover composition
of the present invention also has an effect of preventing the
clogging.
[0102] The remover composition of Embodiment 2 contains a) water in
an amount of 50 to 99.8% by weight. The content of water in the
remover composition is more preferably 60 to 98% by weight, and
even more preferably 70 to 96% by weight, from the viewpoint of
more effective suppression of generation of precipitates and
stability of the composition, operability, environmental issues
such as waste water treatment and the viewpoint of
removability.
[0103] In the remover composition of Embodiment 2, the content of
the compound b) having a solubility (25.degree. C.) in water of 10
g or more/100 g of water is 90% by weight or more of the portion of
the remover composition excluding the water a). The content is
preferably 93% by weight or more, and more preferably 95% by weight
or more, of the portion of the remover composition excluding the
water a) in order to suppress more effectively generation of
precipitates upon water vaporization.
[0104] Further, the present inventors have found that a remover
composition with an alumina dissolution ability of a certain level
or higher and an aluminum etching amount of a certain level or
lower is highly effective for enhancing deposition removability
after ashing of aluminum wirings while suppressing corrosion of
aluminum wirings. Specifically, the remover composition of
Embodiment 2 has another feature that the alumina dissolution
amount as measured according to the standard test (A-2) is 10 ppm
or more, and the aluminum etching amount as measured according to
the standard test (B-2) is 7 nm or less. By using such a remover
composition, there are exhibited effects that excellent
removability of deposition produced during formation of
semiconductor device is obtained and that corrosion of materials
such as wiring metals can be prevented.
[0105] The procedures of the standard test (A-2) and the standard
test (B-2) will be described below.
[0106] <Standard Test (A-2)> [0107] 1) Twenty grams of a
remover composition is placed in a 100-ml polyethylene container,
and kept at a constant temperature in a thermostatic chamber at
40.degree. C. [0108] 2) Next, 0.1 g of an alumina powder (trade
name: "WA-10000," manufactured by Fujimi Corporation; average
particle size: 0.5 .mu.m) is added to the solution, and
sufficiently stirred for 30 minutes. [0109] 3) Ten grams of an
aliquot of the supernatant is placed in a centrifuging tube, and
allowed to separate using a centrifuge (trade name: "himac CP56G,"
manufactured by Hitachi, Ltd.) under conditions at 20,000 r/min for
15 minutes. The light emission intensity from aluminum is
determined for the resulting supernatant using an ICP emission
analyzer (trade name: "JY238," manufactured by Horiba Ltd.). [0110]
4) The alumina dissolution amount is determined from a calibration
curve made using an aqueous solution of aluminum of known
concentrations.
[0111] Incidentally, from the viewpoint of performing the
measurement more excellently, the supernatant is diluted ten-fold
with ultrapure water for measuring the light emission intensity
from aluminum in 3). When the concentration is over the range of
the calibration curve (0 to 2 ppm), the diluted solution is again
diluted ten-fold for the measurement. Also in 4), an aqueous
solution of aluminum (1,000 ppm) is diluted 10,000-fold (0.1 ppm)
and 500-fold (2.0 ppm), respectively, with ultrapure water, and the
resulting dilutions are subjected to an atomic absorption analysis
to make a calibration curve (three-point calibration).
[0112] <Standard Test (B-2)> [0113] 1) A test piece is
prepared by cutting out a 3-cm square piece from a substrate
(thickness: 1 mm) having an aluminum sputtering layer (thickness:
about 500 nm) formed on a silicon wafer by a CVD method. [0114] 2)
The test piece is subjected to pre-cleaning by immersing in a 0.1
wt % aqueous HF solution at room temperature for 30 seconds,
rinsing with water, and drying by blowing nitrogen. The fluorescent
X-ray intensity from aluminum is measured for the resulting test
piece, using a fluorescent X-ray measuring device ("ZSX100e,"
manufactured by Rigaku Denki Kogyo Co., Ltd.) (measurement of film
thickness before immersing in the test aqueous solution). [0115] 3)
Twenty grams of a remover composition is placed in a 100-ml
polyethylene container, and kept at a constant temperature in a
thermostatic chamber at 40.degree. C. [0116] 4) Thereafter, one
test piece is immersed in 20 g of the remover composition kept at a
constant temperature at 40.degree. C. for 30 minutes, rinsed with
ion exchange water and dried by blowing nitrogen. Then, the
fluorescent X-ray intensity from aluminum is measured for the
resulting test piece on the same position as that measured before
immersing, using a fluorescent X-ray measuring device (measurement
of film thickness after immersing in the test aqueous solution).
[0117] 5) The film thicknesses before and after immersing in the
test aqueous solution are calculated from the calibration curve
made previously for aluminum sputtering film of known film
thicknesses using a fluorescent X-ray measuring device.
[0118] The remover composition of Embodiment 2 is one having an
alumina dissolution amount as measured according to the
above-mentioned standard test (A-2) of 10 ppm or more. From the
viewpoint of enhancing deposition removability after ashing, the
alumina dissolution amount is preferably 12 ppm or more, and more
preferably 15 ppm or more. Also, the aluminum etching amount as
measured according to the standard test (B-2) is 7 nm or less and,
from the viewpoint of more effectively preventing corrosion of
aluminum wirings, preferably 5 nm or less, and more preferably 3 nm
or less.
[0119] It is desirable that the above remover composition contains
an acid as well as an inorganic acid salt and/or an organic acid
salt, as the compound b) having a solubility (25.degree. C.) in
water of 10 g or more/100 g of water. Here, the acid acts as a
dissolution agent for eliminating deposition on aluminum wirings
(aluminum oxide dissolution agent), and the inorganic acid salt
and/or the organic acid salt acts as an etching inhibitor for
preventing corrosion of aluminum wirings (aluminum corrosion
inhibitor), thereby to perform efficiently removal cleaning of
deposition on aluminum wirings and titanium-based deposition on the
bottom of via holes and to suppress corrosion of materials such as
aluminum wirings. Also, when the solubilities in water of the acid,
inorganic acid salt and organic acid salt are higher than the above
value, in the case where the remover composition is exposed to high
temperature or continuously used in a circulation system for a long
period of time, cleaning can be performed without generation of
precipitates or contamination of a semiconductor substrate and a
semiconductor device.
[0120] The acid in Embodiment 2 is not particularly limited, as
long as it can satisfy the above requirement. The acid includes,
for example, inorganic acids such as phosphonic acid, sulfuric
acid, nitric acid, phosphoric acid and hydrochloric acid, and
organic acids such as organic phosphonic acid, organic sulfuric
acid, carboxylic acid and organic sulfonic acid. Among them, from
the viewpoint of attaining deposition removability and
anticorrosiveness for wirings at the same time, preferable are
sulfuric acid (solubility of 50 g or more/100 g of water),
hydrochloric acid (solubility of 50 g or more/100 g of water),
nitric acid (solubility of 50 g or more/100 g of water),
methanesulfonic acid (solubility of 50 g or more/100 g of water),
sulfosuccinic acid (solubility of 50 g or more/100 g of water),
oxalic acid (solubility of 11.6 g/100 g of water) and
1-hydroxyethylidene-1,1-diphosphonic acid (solubility of 50 g or
more/100 g of water). In particular, sulfuric acid, oxalic acid and
1-hydroxyethylidene-1,1-diphosphonic acid are preferable. Here, the
"solubility (g/100 g of water)" means the amount of a substance
dissolved in 100 g of water (25.degree. C.).
[0121] The solubility (25.degree. C.) of the acid in 100 g of water
needs to be 10 g or more, from the viewpoint of more effectively
suppressing generation of precipitates and preventing
contamination. The solubility is preferably 15 g or more, and even
more preferably 20 g or more.
[0122] In addition, the content of the acid in the remover
composition is preferably 0.01 to 5% by weight, more preferably
0.03 to 3% by weight, even more preferably 0.05 to 2% by weight,
from the viewpoint of suppressing generation of precipitates and
attaining deposition removability and anticorrosiveness for wirings
at the same time.
[0123] Also, the inorganic acid salt and/or the organic acid salt
used in Embodiment 2 is not particularly limited, as long as it can
satisfy the above requirement. In particular among them, one or
more salts selected from the group consisting of carboxylates,
sulfates, sulfonates, phosphonates, nitrates, hydrochlorides and
borates are desirable. Specifically included are ammonium acetate
(solubility of 50 g or more/100 g of water), ammonium citrate
(solubility of 50 g or more/100 g of water), ammonium
sulfosuccinate (solubility of 50 g or more/100 g of water),
ammonium sulfate (solubility of 43.3 g/100 g of water), ammonium
methanesulfonate (solubility of 50 g or more/100 g of water),
ammonium phosphonate (solubility of 50 g or more/100 g of water),
ammonium nitrate (solubility of 50 g or more/100 g of water),
ammonium chloride (solubility of 28.2 g/100 g of water), and the
like. With regard to the cations, these salts may be amine salts or
quaternary ammonium salts, as well as ammonium salts. The amines
are not particularly limited, as long as they are basic, and
include hydroxylamines such as hydroxylamine and
diethylhydroxylamine; alkylamines such as ethylamine,
propanediamine, dibutylamine and trimethylamine; alkanolamines such
as monoethanolamine, methylethanolamine and methyldiethanolamine;
aromatic amines such as aniline and benzylamine; and the like. The
quaternary ammonium ions which form a quaternary ammonium salt
include tetramethylammonium ion, tetraethylammonium ion,
triethylmethylammonium ion, and the like.
[0124] Among these combinations, in particular, ammonium sulfate,
methyldiethanolamine sulfate and ammonium chloride are preferable,
and ammonium sulfate is most preferable.
[0125] Also, the combination of the acid and the salt is properly
selected from the above-mentioned acids and salts without any
particular limitation. Preferred examples include a combination of
1-hydroxyethylidene-1,1-diphosphonic acid and a sulfate, a
combination of sulfuric acid and a nitrate, a combination of oxalic
acid and a sulfate, and other combinations, from the viewpoint of
the three properties of deposition removability, anticorrosiveness
for wirings and prevention of contamination of objects to be
cleaned being particularly excellent.
[0126] The preferred examples of the combination of the acid and
the salt as mentioned above in Embodiment 1 may be also used as a
preferred example in Embodiment 2.
[0127] The solubility (25.degree. C.) of the inorganic acid salt
and/or the organic acid salt in 100 g of water needs to be 10 g or
more, from the viewpoint of suppressing generation of precipitates
and preventing contamination. The solubility is preferably 20 g or
more, and even more preferably 30 g or more.
[0128] Also, the content of the inorganic acid and/or the organic
acid salt in the remover composition is preferably 0.2 to 40% by
weight, more preferably 0.5 to 30% by weight, and even more
preferably 1 to 20% by weight, in order to suppress generation of
precipitates, and from the viewpoint of anticorrosiveness for metal
materials such as aluminum wirings, homogenous dissolution in
water, and deposition dissolution.
[0129] The formulated weight ratio of the acid to the inorganic
acid salt and/or the organic acid salt (hereinafter also simply
referred to as salt) (acid/salt) in the remover composition of
Embodiment 2 is preferably 2/1 to 1/30, more preferably 1/2 to
1/30, even more preferably 1/4 to 1/30, and even more preferably
1/6 to 1/25, from the viewpoint of attaining deposition
removability and anticorrosiveness for wirings at the same
time.
[0130] With respect to the pH of the remover composition of
Embodiment 2, when the pH is 1 or more, the salt becomes more
effective, so the composition is especially excellent in
anticorrosiveness for wirings. When the pH is 10 or less, the
composition is excellent in deposition removability, in particular,
when the pH is 5 or less, the composition is especially excellent
in removability by the acid of deposition originated from aluminum
wirings, while when the pH is 7 or more the composition is
particularly excellent in removability of deposition originated
from interlayer films during via hole formation.
[0131] Therefore, the pH is preferably 1 to 10 from the viewpoint
of attaining deposition removability and anticorrosiveness for
wirings at the same time. In addition, the pH is more preferably 1
to 6, even more preferably 1 to 5, even more preferably 1 to 4, and
even more preferably 1 to 3, from the viewpoint of excellent
removability of titanium-based deposition produced during via hole
formation.
[0132] Also, the pH is preferably 6 to 10, more preferably 7 to
9.5, and especially preferably 7.5 to 9.0, from the viewpoint of
attaining removability of deposition originated from interlayer
films during via hole formation and anticorrosiveness for wirings
at the same time, and the viewpoint of excellent removability of
deposition originated from film components such as TEOS and
deposition originated from resist.
[0133] The remover composition of Embodiment 2 can also contain a
water-soluble solvent as the component b) to impart permeability
and the like, in addition to the above-mentioned acid and salt. As
the amount of the solvent is increased, the amount of dissolution
of the acid and salt contained is decreased, and thus precipitates
are easily generated. Therefore, the content of the water-soluble
solvent in the remover composition of Embodiment 2 is preferably
30% by weight or less, more preferably 20% by weight or less, and
even more preferably 10% by weight or less.
[0134] In addition, the remover composition may further contain
other additives, if necessary, to an extent that no precipitates
are generated when water evaporates, and the functions of
deposition removability and anticorrosiveness for wirings are not
drastically deteriorated. For instance, it is preferable that a
fluorine-containing compound is not contained, if possible, from
the viewpoint of anticorrosiveness for wirings and an issue of
waste water treatment. However, the compound can be added to an
extent that the above functions are not impaired, and the content
thereof in the composition is preferably 0.1% by weight or less,
more preferably 0.05% by weight or less, even more preferably 0.01%
by weight or less, and even more preferably 0.001% by weight or
less. Especially preferably, no fluorine-containing compound is
contained. Besides, an anticorrosive agent, a surfactant, an
antiseptic and the like can be added in accordance with the
intended purpose.
[0135] The remover composition of Embodiment 2 may be used in any
one of the steps of producing a semiconductor device or a
semiconductor substrate. Specifically, the composition can be used
in a step of producing a semiconductor device, including steps, for
example, after development of resist, after dry etching, after wet
etching and after ashing. Particularly, removability of deposition
on aluminum wirings and anticorrosiveness for aluminum wirings are
excellent. In particular, from the viewpoint of removability of
deposition, it is preferable that the remover composition is used
in the removing step after dry ashing, and the deposition
removability and anticorrosiveness for aluminum wirings are
excellent particularly in a semiconductor substrate or a
semiconductor device with aluminum wirings.
[0136] The concentration of each component in the above-mentioned
remover composition is a concentration which is preferable in its
actual use. A high concentration product of the remover composition
can be prepared and diluted prior to use. As the high concentration
product, preferable is a product comprising 0.01 to 5% by weight of
the acid and 0.2 to 40% by weight of the inorganic acid salt and/or
the organic acid salt. Also, the remover composition prepared in a
two-component form may be used by combining the two components to
form single component at the time of use.
[0137] The remover composition of Embodiment 2 may be prepared by
mixing the water a), the compound b) having a solubility
(25.degree. C.) in water of 10 g or more/100 g of water and, if
necessary other additives by known methods.
[0138] The cleaning method for a semiconductor (specifically
semiconductor substrate or semiconductor device) in Embodiment 2
has a feature that a semiconductor substrate or a semiconductor
device is subjected to removal cleaning by using the above remover
composition. The means for removal cleaning include immersing
removal cleaning, oscillation removal cleaning, single wafer
removal cleaning, removal cleaning utilizing a rotating means such
as a spinner, paddle cleaning, removal cleaning by spraying in air
or a liquid, ultrasonic removal cleaning and the like. Among them,
immersing removal cleaning and oscillation removal cleaning are
suitable.
[0139] The cleaning temperature is preferably in the range of
20.degree. to 60.degree. C., and even more preferably 20.degree. to
40.degree. C., for suppressing generation of precipitates, and from
the viewpoint of deposition dissolution, deposition removability,
anticorrosiveness for metal wiring materials, safety and
operability.
[0140] In the rinsing step after cleaning with the remover
composition of Embodiment 2, water rinsing can be employed.
Conventional removers based on ammonium fluoride or based on an
amine such as hydroxylamine are a solvent-based remover, so that
they are difficult to be rinsed off with water. In addition, there
is a possibility of corrosion of wirings and the like occurring
when these removers are mixed with water. For that reason, there
has been generally employed a method of rinsing with a solvent such
as isopropanol. However, the remover composition of Embodiment 2 is
highly anticorrosive for wirings even under excessive water since
the composition is water-based and the composition contains the
salt mentioned above thereby to suppress corrosion of wirings.
Therefore, water rinsing can be employed, which provides an
economical cleaning method for semiconductor, with highly reduced
environmental damage.
[0141] The method of producing a semiconductor of Embodiment 2 is a
method including the step of cleaning using the above-mentioned
cleaning method. Specifically, the method of Embodiment 2 has a
feature that the method includes a step of removal cleaning for a
semiconductor substrate or a semiconductor device by using the
remover composition. Incidentally, specific operations for the
removal cleaning are not particularly limited, as long as they are
the same as those described above. The semiconductor substrate or
semiconductor device, obtained by using the above remover
composition and the above method of cleaning a semiconductor
substrate or a semiconductor device, has no remaining deposition,
with highly reduced corrosion of metal wiring materials. Also, the
composition and method can be used for removal cleaning for a
semiconductor substrate or a semiconductor device with wirings
having a narrow wiring width of 180 nm or less, to which
conventional removers cannot be applied due to wiring corrosion.
Therefore, the remover composition and method can be suitably used
for producing smaller and higher performance electronic parts such
as LCDs, memories and CPUs.
[0142] Incidentally, the invention of Embodiment 2 is suitable for
a semiconductor substrate or a semiconductor device having wirings
containing a metal such as aluminum, copper, tungsten or titanium,
and excellent in removability of aluminum- and titanium-based
deposition, so that it is particularly suitable for a semiconductor
substrate or a semiconductor device in which a wiring material
comprising aluminum and/or titanium is used.
Embodiment 3
[0143] Also, the present inventors have found that when pH change
in removal cleaning liquid is minimized during the cleaning of a
semiconductor such as a semiconductor substrate or a semiconductor
device, a condition can be kept in which deposition eliminability
is high and anticorrosiveness for wirings is high, allowing for
continuous cleaning, and thus completed the invention of Embodiment
3. In particular, for a semiconductor substrate or a semiconductor
device with aluminum wirings having a narrow wiring width, since
only a small amount of wiring corrosion can significantly affect
the performance, stable cleaning performance is important.
[0144] Specifically, the remover composition of Embodiment 3 is a
water-based remover composition, containing an aluminum oxide
dissolution agent and an aluminum corrosion inhibitor, wherein the
water-based remover composition has: 1) a water content of 50% by
weight or more; 2) an aluminum oxide dissolution amount as measured
according to the standard test (A-2) of 10 ppm or more; 3) an
aluminum etching amount as measured according to the standard test
(B-2) of 7 nm or less; and provides 4) a pH change before and after
the standard test (A) of 0.5 or less. By cleaning semiconductors
using the remover composition, there is exhibited an effect that
excellent removability of deposition produced during the formation
of a semiconductor device and excellent anticorrosiveness for
materials such as wiring metals are obtained over a long period of
time.
[0145] Here, the standard test (A-2) and the standard test (B-2)
are the same as those descried above.
[0146] It is desirable that the remover composition of Embodiment 3
is one having an aluminum oxide dissolution amount as measured
according to the above-mentioned standard test (A-2) of 10 ppm or
more and, from the viewpoint of enhancing deposition removability
after ashing, preferably 12 ppm or more, and more preferably 15 ppm
or more. Also, It is desirable that the aluminum etching amount as
measured according to the standard test (B-2) is 7 nm or less and,
from the viewpoint of preventing corrosion of aluminum wirings,
preferably 5 nm or less, and more preferably 3 nm or less.
[0147] Further, it has been found that it is necessary to minimize
pH changes during cleaning in order for the remover composition of
Embodiment 3 to retain the cleaning ability for a long period of
time (or to have an applicability for continuous cleaning). As a
measure for this, a pH change before and after the standard test
(A-2) can be used, and it is important that the amount of change is
0.5 or less. A method of measuring the pH change before and after
the standard test (A-2) includes measuring the pH of the remover
composition at 25.degree. C. in advance, carrying out the standard
test (A-2), thereafter setting again the remover composition at
25.degree. C. and measuring the pH of the composition, and
calculating the pH difference before and after the test as the pH
change. When the pH change is 0.5 or less, a change in deposition
removability and a change in performance of anticorrosiveness for
aluminum wirings in the remover composition are minimized, which
allows for continuous cleaning. The pH change is preferably 0.4 or
less, and more preferably 0.3 or less, from the viewpoint of
enhancing applicability for long-term continuous cleaning.
[0148] The remover composition of Embodiment 3 contains an aluminum
oxide dissolution agent and an aluminum corrosion inhibitor.
[0149] The aluminum oxide dissolution agent refers to an agent
which dissolves aluminum oxide, and is preferably an acid due to
its excellent dissolubility. The acid includes, for example,
inorganic acids such as phosphonic acid, sulfuric acid, nitric
acid, phosphoric acid and hydrochloric acid, and organic acids such
as organic phosphonic acid, organic sulfuric acid, carboxylic acid
and organic sulfonic acid. Among them, from the viewpoint of
attaining deposition removability and anticorrosiveness for wirings
at the same time, sulfuric acid, hydrochloric acid, nitric acid,
methanesulfonic acid, sulfosuccinic acid, oxalic acid and
1-hydroxyethylidene-1,1-diphosphonic acid are preferable and, in
particular, sulfuric acid, oxalic acid and
1-hydroxyethylidene-1,1-diphosphonic acid are preferable.
[0150] The content of the aluminum oxide dissolution agent is
preferably 0.01 to 5% by weight, more preferably 0.01 to 3% by
weight, even more preferably 0.01 to 2% by weight, and especially
preferably 0.05 to 2% by weight, from the viewpoint of
well-balanced deposition removability and anticorrosiveness for
wirings, and from the viewpoint of reducing pH change during
cleaning.
[0151] The aluminum corrosion inhibitor refers to an agent which
has an effect of preventing corrosion of aluminum, and is
preferably an inorganic acid salt and/or an organic acid salt due
to its excellent corrosion preventive effect. Further, the
inorganic acid salt and the organic acid salt have an action to
suppress pH change when metal oxides and the like as deposition are
dissolved, and are presumed to serve as a buffer. As the inorganic
acid salt and the organic acid salt, one or more salts selected
from the group consisting of carboxylates, sulfates, sulfonates,
phosphonates, nitrates, hydrochlorides and borates are desirable.
Specifically included are ammonium acetate, ammonium citrate,
ammonium oxalate, ammonium sulfosuccinate, ammonium sulfate,
ammonium methanesulfonate, ammonium phosphonate, ammonium nitrate,
ammonium chloride, ammonium tetraborate, and the like. With regard
to the cations, these salts may be amine salts or quaternary
ammonium salts, as well as ammonium salts. The amines are not
particularly limited, as long as they are basic, and include
hydroxylamines such as hydroxylamine and diethylhydroxylamine;
alkylamines such as ethylamine, propanediamine, dibutylamine and
trimethylamine; alkanolamines such as monoethanolamine,
methylethanolamine and methyldiethanolamine; aromatic amines such
as aniline and benzylamine; and the like. The quaternary ammonium
ions which form a quaternary ammonium salt include
tetramethylammonium ion, tetraethylammonium ion,
triethylmethylammonium ion, lauryltrimethylammonium ion,
benzyltrimethylammonium ion, and the like. Among these
combinations, ammonium sulfate, tetramethylammonium sulfate,
methylethanolamine sulfate, methyldiethanolamine sulfate and
ammonium chloride are especially preferable, and ammonium sulfate
is most preferable.
[0152] The content of the aluminum corrosion inhibitor in the
remover composition of Embodiment 3 is preferably 0.2 to 40% by
weight, more preferably 0.5 to 30% by weight, even more preferably
1 to 20% by weight, and especially preferably 5 to 10% by weight,
from the viewpoint of suppressing pH change during cleaning in
order to maintain anticorrosiveness for metal materials such as
aluminum wirings and deposition dissolubility.
[0153] The formulated weight ratio of the aluminum oxide
dissolution agent to the aluminum corrosion inhibitor (aluminum
oxide dissolution agent/aluminum corrosion inhibitor) in Embodiment
3 is preferably 2/1 to 1/30, more preferably 1/2 to 1/30, even more
preferably 1/4 to 1/30, and even more preferably 1/6 to 1/25, from
the viewpoint of performing continuous cleaning with maintaining
deposition removability and anticorrosiveness for wirings.
[0154] In addition, the combination of the aluminum oxide
dissolution agent and the aluminum corrosion inhibitor is properly
selected from the aluminum oxide dissolution agents and the
aluminum corrosion inhibitors mentioned above, without any
particular limitation. Preferred examples include a combination of
1-hydroxyethylidene-1,1-diphosphonic acid and a sulfate, a
combination of sulfuric acid and a nitrate, a combination of oxalic
acid and a phosphonate, and other combinations, from the viewpoint
of the three properties of deposition removability,
anticorrosiveness for wirings and small pH change being
particularly excellent.
[0155] The preferred examples of the combination of the dissolution
agent and the inhibitor as mentioned above in Embodiment 1 may be
also used as a preferred example in Embodiment 3.
[0156] With respect to the pH of the remover composition of
Embodiment 3, when the pH is 1 or more, the aluminum corrosion
inhibitor becomes more effective, so the composition is especially
excellent in anticorrosiveness for wirings. When the pH is 10 or
less, the composition is excellent in deposition removability, in
particular, when the pH is 6 or less, the composition is especially
excellent in removability of deposition originated from aluminum
wirings by the aluminum oxide dissolution agent, while when the pH
is 7 or more the composition is particularly excellent in
removability of deposition originated from interlayer films during
hole formation.
[0157] Therefore, the pH is preferably 1 to 10 from the viewpoint
of attaining deposition removability and anticorrosiveness for
wirings at the same time. In addition, the pH is more preferably 1
to 6, even more preferably 1 to 5, even more preferably 1 to 4, and
even more preferably 1 to 3, from the viewpoint of excellent
removability of titanium-based deposition produced during via hole
formation.
[0158] Also, the pH is preferably 6 to 10, more preferably 7 to
9.5, and especially preferably 7.5 to 9.0, from the viewpoint of
attaining removability of deposition originated from interlayer
films during hole formation and anticorrosiveness for wirings at
the same time, and the viewpoint of excellent removability of
deposition originated from film components such as TEOS and
deposition originated from resist.
[0159] Further, the remover composition may contain other
additives, if necessary, to the extent that the deposition
removability and anticorrosiveness for wirings are retained and the
change in pH is not large. For example, a water-soluble solvent may
be added in order to impart permeability and the like, and the
content thereof is preferably 30% by weight or less, more
preferably 20% by weight or less, and even more preferably 10% by
weight or less. The water-soluble solvent includes glycol compounds
such as butyl diglycol. In addition, it is preferable that a
fluorine-containing compound is not contained, if possible, from
the viewpoint of anticorrosiveness for wirings and an issue of
waste water treatment. However, the compound can be added to an
extent that the above functions are not impaired, and the content
thereof in the composition is preferably 0.1% by weight or less,
more preferably 0.05% by weight or less, even more preferably 0.01%
by weight or less, and even more preferably 0.001% by weight or
less. Especially preferably, no fluorine-containing compound is
contained. Besides, an anticorrosive agent, a surfactant, an
antiseptic and the like can be added in accordance with the
intended purpose.
[0160] The remover composition of Embodiment 3 can be prepared by
mixing the above-mentioned aluminum oxide dissolution agent, the
aluminum corrosion inhibitor and the like in a medium by known
methods. Also, the remover composition prepared in a two-component
form may be used by combining the two components to form single
component at the time of use.
[0161] Since the method of continuous cleaning of Embodiment 3 has
a step of cleaning at 60.degree. C. or lower by using the
above-mentioned remover composition and allows excellent deposition
removability and anticorrosiveness for wirings to be retained even
in a long-term cleaning, the method can be used in removal cleaning
for a semiconductor substrate or a semiconductor device with
wirings having a wiring width as narrow as 180 nm or less, to which
conventional methods cannot be applied. In semiconductor substrates
with wirings having a wiring width of 500 nm or more, even if
wiring metal corrosion during deposition elimination is not minor,
this is not likely to be problematic because the electric
resistance will not be increased easily due to the wide wiring
width. However, for narrow wirings having a wiring width of 180 nm
or less, in accordance with higher-speed and more highly integrated
devices, a large amount of corrosion results in a significant
increase in electric resistance, which may cause a conductive
defect. In such a situation, the method of continuous cleaning of
Embodiment 3 can be advantageously applied to a semiconductor
substrate or a semiconductor device with wirings having a narrow
wiring width, particularly to a semiconductor substrate or a
semiconductor device with aluminum wirings having a wiring width as
narrow as 180 nm or less, since a condition can be continuously
kept in which deposition removability is high and amount of wiring
metal corrosion is highly reduced.
[0162] In the method of continuous cleaning of Embodiment 3, the
means for removal cleaning for a semiconductor substrate or a
semiconductor device are not particularly limited, and include
immersing removal cleaning, oscillation removal cleaning, single
wafer removal cleaning, removal cleaning utilizing a rotating means
such as a spinner, paddle cleaning, removal cleaning by spraying in
air or a liquid, ultrasonic removal cleaning and the like. Among
them, immersing removal cleaning and oscillation removal cleaning
are suitable.
[0163] The cleaning temperature is 60.degree. C. or lower,
preferably 50.degree. C. or lower, from the viewpoint of deposition
dissolution, deposition removability, anticorrosiveness for metal
wiring materials, safety and operability. Incidentally, there is no
particular limitation to the other cleaning conditions in the
above-mentioned means for removal cleaning.
[0164] In the rinsing step after cleaning with the remover
composition, water rinsing can be employed. Conventional removers
based on ammonium fluoride or based on an amine such as
hydroxylamine are a solvent-based remover, so that they are
difficult to be rinsed off with water. In addition, there is a
possibility of corrosion of wirings and the like occurring when
these removers are mixed with water. For that reason, there has
been generally employed a method of rinsing with a solvent such as
isopropanol. However, the remover composition of Embodiment 3 is
highly anticorrosive for wirings even under excessive water since
the composition is water-based and the composition contains the
inhibitor thereby to suppress corrosion of wirings. Therefore,
water rinsing can be employed, which provides an economical removal
cleaning method, with highly reduced environmental damage.
[0165] The method of producing a semiconductor (for example,
semiconductor substrate or semiconductor device) of Embodiment 3 is
a method including the step of cleaning using the above-mentioned
method of continuous cleaning. Specifically, the method of
Embodiment 3 has a feature that the method includes a step of
cleaning a semiconductor substrate or a semiconductor device by
using the above-mentioned method of continuous cleaning. The
semiconductor substrate or semiconductor device, obtained by using
the method of continuous cleaning, has highly reduced amount of
remaining deposition and corrosion of metal wiring materials. Also,
the method can be used for removal cleaning for a semiconductor
substrate or a semiconductor device with wirings having a narrow
wiring width of 180 nm or less, to which conventional cleaning
methods cannot be applied. Therefore, the method can be suitably
used for producing smaller and higher performance electronic parts
such as LCDs, memories and CPUs.
[0166] Incidentally, the invention of Embodiment 3 is suitable for
production of a semiconductor substrate or a semiconductor device
having wirings containing a metal such as aluminum, copper,
tungsten or titanium, and excellent in removability of aluminum-
and titanium-based deposition, so that it is particularly suitable
for production of a semiconductor substrate or a semiconductor
device in which a wiring material comprising aluminum and/or
titanium is used.
EXAMPLES
[0167] Now the present invention will be described and explained in
more detail by way of Examples. These Examples merely disclose the
present invention and are not intended to limit the present
invention.
Examples I-1 to I-15 and Comparative Examples I-1 to I-11
I-1. Alumina Dissolution Test and Aluminum Etching Test
[0168] Table 1 shows the results of alumina dissolution amounts for
the dissolution agents, as measured according to the standard test
(A-1), and Table 2 shows the results of aluminum etching amounts
for the inhibitors, as measured according to the standard test
(B-1). TABLE-US-00001 TABLE 1 Alumina Dissolution Dissolution Agent
Amount (ppm) Phosphoric Aid 26 Phosphonic Acid 31 Hydrochloric Acid
16 Nitric Acid 15 Sulfuric Acid 22 Boric Acid 1 Sulfosuccinic Acid
13 Methanesulfonic Acid 17 Oxalic Acid 26 1-Hydroxyethylidene-1,1-
20 Diphosphonic Acid (HEDP) Dodecylbenzenesulfonic Acid (LAS) 5
Propionic Acid 5 Phthalic Anhydride No Dissolution Isobutyric Acid
6 Acetic Acid 7 Ethylenediamine Tetraacetic Acid No Dissolution
Sulfuric Acid + Oxalic Acid.sup.1) 33 Isobutyric Acid + Acetic
Acid.sup.1) 11 .sup.1)The mixing ratio of the two components was
50/50 (weight ratio) and the total amount was adjusted so as to
form a 0.2 wt % aqueous solution.
[0169] TABLE-US-00002 TABLE 2 Aluminum Etching Inhibitor Amount
(nm) Without Addition 8.0 Ammonium Phosphonate 6.0 Ammonium Nitrate
6.1 Ammonium Chloride 1.8 Ammonium Sulfate 3.0 Methyldiethanolamine
Sulfate 3.2 Tetramethylammonium Sulfate 3.5 Ammonium Tetraborate
5.9 Ammonium Phosphate 44.6 Ammonium Fluoride >500 Ammonium
Acetate 0 Ammonium Citrate 0 Ammonium Oxalate 2.7 Ammonium
Sulfosuccinate 1.0 Ammonium Methanesulfonate 1.2
Tetramethylammonium Formate 0.6 Tetramethylammonium Acetate 1.5
Sodium Polyoxyetylene Lauryl Ether Sulfate 7.5
I-2. Wafer for Evaluation
[0170] Under the following conditions, patterned wafers with
aluminum (Al) wirings respectively having a wiring width of 0.5
.mu.m (500 nm) and 0.18 .mu.m (180 nm), and a patterned wafer with
holes having a diameter of 0.5 .mu.m (500 nm) were cut into a 1-cm
square piece, and the pieces were used for the cleaning test.
(Structure of Aluminum Wirings)
[0171] TiN/Al--Si/TiN/Ti/SiO.sub.2/Substrate
I-3. Preparation of Remover Composition
[0172] Remover compositions having compositions (each numerical
value: % by weight), shown in Tables 3 and 4, were prepared using
the dissolution agents and inhibitors shown in Tables 1 and 2.
I-4. Evaluation of Removability
[0173] (1) Removing Method: A wafer for evaluation was immersed in
30 ml of a remover composition to perform removal at 40.degree. C.
for 15 minutes. [0174] (2) Rinsing Method: The wafer for evaluation
was immersed in 30 ml of ultrapure water at 25.degree. C. for 1
minute, and this step was repeated twice to complete rinsing.
[0175] (3) Evaluation Method: The wafer for evaluation after
rinsing was dried. Thereafter, the removability of deposition on
aluminum wirings and the removability of deposition originated from
interlayer films of the patterned wafer with holes, as well as the
anticorrosiveness were evaluated based on the following four
ratings, using an FE-SEM (scanning electron microscope) at a
magnification of 50,000 to 100,000.
[0176] Here, only Comparative Example 9 was evaluated by changing
the immersion conditions in the Removing Method to those at
25.degree. C. for 5 minutes.
(Removability of Deposition on Al wirings/Removability of
Deposition Originated From Interlayer Film)
[0177] .circleincircle.: Remaining deposition is not confirmed at
all.
[0178] .smallcircle.: A part of deposition remains.
[0179] .DELTA.: Substantial deposition remains.
[0180] .times.: Deposition cannot be removed.
(Anticorrosiveness for Al Wirings)
[0181] .circleincircle.: Corrosion of Al wirings is not confirmed
at all.
[0182] .smallcircle.: A part of insulating materials are
corroded.
[0183] .DELTA.: Substantial insulating materials are corroded.
[0184] .times.: Insulating materials are corroded.
[0185] Here, acceptable products are one rated as
".circleincircle." or ".smallcircle." for both of the removability
of deposition on aluminum wirings or removability of deposition
originated from interlayer films, and the anticorrosiveness for
aluminum wirings. TABLE-US-00003 TABLE 3 Remover Composition Other
Dissolution Agent Inhibitor Water Additives Dilution Ex. Nos. (% by
weight) (% by weight) % by weight (% by weight) pH Ratio.sup.1) I-1
Phosphonic Acid (0.2) Ammonium Methanesulfonate (5.0) 94.8 3.5 1
I-2 Sulfuric Acid (1.0) Ammonium Nitrate (25.0) 74.0 3.1 1 I-3
Sulfuric Acid (1.0) Ammonium Nitrate (25.0) 74.0 3.1 5 I-4 Oxalic
Acid (1.0) Ammonium Phosphonate (30.0) 69.0 2.3 1 I-5 Oxalic Acid
(1.0) Ammonium Phosphonate (30.0) 69.0 2.3 5 I-6 Sulfosuccinic Acid
(0.5) Ammonium Chloride (4.0) 92.5 DMSO (3.0) 3.2 1 I-7 HEDP (1.0)
Ammonium Sulfate (20.0) 79.0 2.1 1 I-8 HEDP (1.0) Ammonium Sulfate
(20.0) 79.0 2.8 5 I-9 HEDP (0.2) Ammonium Sulfate (4.0) 95.8 2.2 1
I-10 HEDP (1.0) Ammonium Sulfate (5.0) 94.0 2.2 1 I-11 HEDP (2.0)
Ammonium Sulfate (5.0) 93.0 1.9 1 I-12 HEDP (5.0) Ammonium Sulfate
(5.0) 90.0 1.6 1 I-13 Sulfuric Acid (0.1) Ammonium Sulfate (5.0)
94.8 2.3 1 Oxalic Acid (0.1) I-14 HEDP (0.2) Ammonium Sulfate (4.0)
95.8 8.0.sup.2) 1 I-15 HEDP (0.2) Ammonium Sulfate (4.0) 95.8
9.0.sup.3) 1 Evaluation Results Wiring Width of 500 nm Wiring Width
of 180 nm Deposition Deposition Anti- Ex. Nos. Removability
Anticorrosiveness Removability Corrosiveness I-1 .circleincircle.
.circleincircle. .circleincircle. .largecircle. I-2
.circleincircle. .circleincircle. .circleincircle. .largecircle.
I-3 .circleincircle. .circleincircle. .circleincircle.
.largecircle. I-4 .circleincircle. .circleincircle.
.circleincircle. .largecircle. I-5 .largecircle. .circleincircle.
.circleincircle. .circleincircle. I-6 .largecircle.
.circleincircle. .largecircle. .circleincircle. I-7
.circleincircle. .circleincircle. .largecircle. .circleincircle.
I-8 .circleincircle. .circleincircle. .circleincircle.
.circleincircle. I-9 .circleincircle. .circleincircle.
.circleincircle. .circleincircle. I-10 .circleincircle.
.circleincircle. .circleincircle. .circleincircle. I-11
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
I-12 .circleincircle. .largecircle. .circleincircle. .largecircle.
I-13 .circleincircle. .circleincircle. .circleincircle.
.circleincircle. I-14 .circleincircle..sup.4)
.circleincircle..sup.4) .circleincircle. .circleincircle. I-15
.circleincircle..sup.4) .largecircle..sup.4) .circleincircle.
.largecircle. .sup.1)The numerical values described for dilution
ratio are a value obtained through the use of water in the
dilution, and "1" indicates one-fold dilution (stock solution) and
"5" indicates 5-fold dilution. .sup.2)The pH was adjusted with an
aqueous ammonia. .sup.3)The pH was adjusted with an amine.
.sup.4)The evaluations for wirings having a wiring width of 500 nm
in Examples I-14 and I-15 are both an evaluation of removability of
deposition originated from interlayer film of a patterned wafer
with holes.
[0186] TABLE-US-00004 TABLE 4 Remover Composition Other Comp.
Dissolution Agent Inhibitor Water Additives Dilution Ex. Nos. (% by
weight) (% by weight) % by weight (% by weight) pH Ratio.sup.2) I-1
HEDP (0.2) -- 99.8 -- 1.8 1 I-2 Phosphonic Acid (0.2) -- 99.8 --
1.2 1 I-3 -- Ammonium Sulfate (4.0) 96.0 -- 5.3 1 I-4 -- Ammonium
Acetate (5.0) 95.0 -- 4.8 1 I-5 Boric Acid (0.5) Ammonium Nitrate
(5.0) 94.5 -- 5.6 1 I-6 LAS (0.5) Ammonium Nitrate (5.0) 94.5 --
5.6 1 I-7 Hydrochloric Acid (2.0) Ammonium Phosphate (25.0) 73.0 --
3.5 1 I-8 Hydrochloric Acid (2.0) Ammonium Phosphate (25.0) 73.0 --
3.5 5 I-9.sup.1) Propionic Acid (5.0) Tetramethylammonium Formate
41.9 NH.sub.4F (8) 2.6 1 (5.0) DMF (40) EP120A (0.1) I-10 Propionic
Acid (5.0) Tetramethylammonium Formate 41.9 NH.sub.4F (8) 2.6 1
(5.0) DMF (40) EP120A (0.1) I-11 Acetic Acid (10.0) Sodium
Polyoxyethylene Lauryl 80.0 -- 3.6 1 Ether Sulfate (10.0)
Evaluation Results Wiring Width of 500 nm Wiring Width of 180 nm
Deposition Deposition Anti- Ex. Nos. Removability Anticorrosiveness
Removability Corrosiveness I-1 .circleincircle. .DELTA.
.circleincircle. X I-2 .circleincircle. X .circleincircle. X I-3 X
.circleincircle. .DELTA. .circleincircle. I-4 X .circleincircle. X
.circleincircle. I-5 .DELTA. .circleincircle. .DELTA.
.circleincircle. I-6 X .circleincircle. .DELTA. .circleincircle.
I-7 .circleincircle. .DELTA. .circleincircle. X I-8
.circleincircle. X .circleincircle. X I-9.sup.1) .DELTA.
.largecircle. .DELTA. X I-10 .circleincircle. .DELTA.
.circleincircle. X I-11 .largecircle. .DELTA. .largecircle. X
.sup.1)Immersing at 25.degree. C. for 5 minutes .sup.2)The
numerical values described for dilution ratio are a value obtained
through the use of water in the dilution, and "1" indicates
one-fold dilution (stock solution) and "5" indicates 5-fold
dilution. Incidentally, in the Tables, HEDP represents
1-hydroxyethylidene-1,1-diphosphonic acid, LAS represents
dodecylbenzenesulfonic acid, DMSO represents dimethylsulfoxide, DMF
represents dimethylformamide, and EP120A represents a
polyoxyethylene phenyl ether (manufactured by Dai-Ichi Kogyo
Seiyaku Co., Ltd).
[0187] It can be seen from the results in Tables 3 and 4 that the
remover compositions obtained in Examples I-1 to I-15 are all
excellent in deposition removability and anticorrosiveness, and
causes drastically suppressed corrosion even in wirings having such
a narrow wiring width as 180 nm, as compared with those obtained in
Comparative Examples I-1 to I-11. Also, it can be seen that the
remover compositions obtained in Examples I-1 to I-15 have an
excellent deposition removability even when the immersion time is
as short as 15 minutes.
Examples II-1 II-2 and Comparative Examples II-1. II-2
II-1. Preparation of Remover Composition
[0188] Remover compositions having compositions (each numerical
value: % by weight), shown in Table 5, were prepared and used for
the evaluation. TABLE-US-00005 TABLE 5 Inorganic Acid Acid Salt
and/or Organic Acid Salt Water Solubility Solubility Amount (g/100
g of Amount (g/100 g of Amount (% by Kind water) (% by weight) Kind
water) (% by weight) weight) Ex. Sulfuric Acid 100 or 0.3 Ammonium
100 or 5.0 94.7 II-1 more Nitrate more Ex. Oxalic Acid 11.6 0.2
Ammonium 43.3 8.0 91.8 II-2 Sulfate Comp. Acetic Acid 100 or 0.5
Ammonium 5.0 2.5 97.0 Ex. II-1 more Oxalate Comp. Benzoic Acid 0.34
0.2 Ammonium 28.2 5.0 94.8 Ex. II-2 Chloride
II-2. Wafer for Evaluation
[0189] Under the following conditions, patterned wafers with
aluminum (Al) wirings respectively having a wiring width of 500 nm
and 180 nm were cut into a 1-cm square piece, and the pieces were
used for the cleaning test.
(Structure of Aluminum Wirings)
[0190] TiN/Al--Si/TiN/Ti/SiO.sub.2/Substrate
II-3. Evaluation of Removability
[0191] (1) Removing Method: A wafer for evaluation was immersed in
30 ml of a remover composition to perform removal at 40.degree. C.
for 15 minutes. [0192] (2) Rinsing Method: The wafer for evaluation
was immersed in 30 ml of ultrapure water at 25.degree. C. for 1
minute, and this step was repeated twice to complete rinsing.
[0193] (3) Evaluation Method: The wafer for evaluation after
rinsing was dried. Thereafter, the removability of deposition on
aluminum wirings, and the corrosiveness were evaluated based on the
following four ratings, using an FE-SEM (scanning electron
microscope) at a magnification of 50,000 to 100,000. (Removability
of Deposition on Aluminum wirings)
[0194] .circleincircle.: Remaining deposition is not confirmed at
all.
[0195] .smallcircle.: A part of deposition remains.
[0196] .DELTA.: Substantial deposition remains.
[0197] .times.: Deposition cannot be removed.
(Anticorrosiveness for Aluminum Wirings)
[0198] .circleincircle.: Corrosion of aluminum wirings is not
confirmed at all.
[0199] .smallcircle.: There is partial corrosion of insulating
materials.
[0200] .DELTA.: There is considerable corrosion of insulating
materials.
[0201] .times.: There is marked corrosion of insulating
materials.
[0202] Here, acceptable products are one rated as
".circleincircle." or ".smallcircle." for both of the removability
of deposition on aluminum wirings and the anticorrosiveness for
aluminum wirings.
II-4. Method of Evaluating Precipitates
[0203] One-hundred grams of a remover composition was placed in a
200-ml beaker, and left for 10 hours in an open system under
stirring with a stirrer in a thermostat at 40.degree. C. with the
top opened. Thereafter, the beaker was taken out, and the presence
or absence of precipitates was visually confirmed.
[0204] Incidentally, the aluminum oxide dissolution amount and the
aluminum etching amount for the resulting remover composition were
measured according to the above-mentioned standard tests (A-2) and
(B-2).
[0205] The results are shown in Table 6. TABLE-US-00006 TABLE 6
Aluminum Precipitates Oxide Aluminum Wiring Width of 500 nm Wiring
Width of 180 nm After Dissolution Etching Corrosiveness
Corrosiveness Circulation Amount Amount Deposition for Aluminum
Deposition for Aluminum at 40.degree. C. for pH (ppm) (nm)
Removability Wirings Removability Wirings 10 hours Ex. 2.1 21.3 2.6
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
Absent II-1 Ex. 2.8 18.6 3.8 .circleincircle. .circleincircle.
.circleincircle. .largecircle. Absent II-2 Comp. 3.1 8.7 5.8
.DELTA. .largecircle. .largecircle. .DELTA. Present.sup.1) Ex. II-1
Comp. 3.5 7.6 4.3 .DELTA. .largecircle. .DELTA. .largecircle.
Present.sup.1) Ex. II-2 .sup.1)White precipitates were formed on
the liquid surface of the remover composition along the wall of the
container.
[0206] It can be seen from the results in Tables 5 and 6 that the
remover compositions obtained in Examples II-1 and II-2 are
excellent in both of removability of deposition on aluminum wirings
and anticorrosiveness, and are free from precipitates after storage
for a long period of time, as compared with those obtained in
Comparative Examples II-1 and II-2.
[0207] Particularly, it can be seen that the remover compositions
of Examples II-1 and II-2 still exhibit an excellent deposition
removability and anticorrosiveness for aluminum wirings having such
a narrow wiring width as 180 nm.
Examples III-1 to III-3 and Comparative Examples III-1 to III-3
III-1. Remover Composition
[0208] Remover compositions having compositions, as shown in Table
7, were prepared and used for the evaluation. TABLE-US-00007 TABLE
7 Aluminum Oxide Aluminum Aluminum Oxide Aluminum Corrosion
Dissolution Etching Dissolution Agent Inhibitor Others Water Amount
Amount Kind Amount.sup.1) Kind Amount.sup.1) Kind Amount.sup.1)
Amount.sup.1) (ppm) (nm) Ex. HEDP 0.3 Ammonium 4.5 -- -- 95.2 19.8
3.4 III-1 Sulfate Ex. Oxalic 0.3 Ammonium 5.0 -- -- 94.7 20.2 5.6
III-2 Acid Nitrate Ex. Oxalic 0.5 Ammonium 8.0 BDG 3.0 88.5 21.8
3.8 III-3 Acid Chloride Comp. Phosphoric 0.5 -- -- -- -- 99.5 16.5
9.2 Ex. III-1 Acid Comp. HEDP 0.3 -- -- -- -- 99.7 18.2 8.0 Ex.
III-2 Comp. Oxalic 0.2 -- -- BDG 5.0 94.8 17.6 10.0 Ex. III-3 Acid
.sup.1)% by weight
[0209] In the Table, HEDP and BDG represent
1-hydroxyethylidene-1,1-diphosphonic acid and butyl diglycol,
respectively.
III-2. Standard Test (A-2) and Standard Test (B-2)
[0210] According to methods of the Standard Tests described above,
aluminum oxide dissolution amount and aluminum etching amount were
determined. The results are shown in Table 7.
III-3. Measurement of pH Change
[0211] The pH of the remover composition before raising the
temperature in the above 1) of standard test (A-2) was determined
at 25.degree. C., which was defined as "initial" pH. Thereafter,
the composition was centrifuged in 3) via the process of 2), and
then the pH of the supernatant was measured, which was defined as
pH "after standard test" (25.degree. C.). The absolute value of
these two values was defined as "amount of change" in pH, and the
results are shown in Table 7.
III-4. Wafer for Evaluation
[0212] Under the following conditions, patterned wafers with
aluminum (Al) wirings respectively having a wiring width of 0.5
.mu.m (500 nm) and 0.18 .mu.m (180 nm) were cut into a 1-cm square
piece, and the pieces were used for the cleaning test.
(Structure of Aluminum Wirings)
[0213] TiN/Al--Si/TiN/Ti/SiO.sub.2/Substrate
III-5. Evaluation of Removability
1) Initial Removability
[0214] (1) Removing Method: A wafer for evaluation was immersed in
30 ml of a remover composition to be subjected to a removal
treatment at 40.degree. C. for 15 minutes. [0215] (2) Rinsing
Method: The wafer for evaluation was immersed in 30 ml of ultrapure
water at 25.degree. C. for 1 minute, and this step was repeated
twice to complete rinsing. [0216] (3) Evaluation Method: The wafer
for evaluation after rinsing was dried. Thereafter, the
removability of deposition on aluminum wirings, and the
anticorrosiveness were evaluated based on the following four
ratings, using an FE-SEM (scanning electron microscope) at a
magnification of 50,000 to 100,000. 2) Removability after Standard
Tests [0217] (1) Removing Method: The wafer was immersed in 30 ml
of a remover composition after the Standard Tests to perform
removal at 40.degree. C. for 15 minutes. The procedures of (2) and
(3) were carried out in the same manner as in Initial Removability
to evaluate removability of deposition on aluminum wirings and
anticorrosiveness. (Removability of Deposition on Aluminum
Wirings)
[0218] .circleincircle.: Remaining deposition is not confirmed at
all.
[0219] .smallcircle.: A part of deposition remains.
[0220] .DELTA.: Substantial deposition remains.
[0221] .times.: Deposition cannot be removed.
(Anticorrosiveness for Aluminum Wirings)
[0222] .circleincircle.: Corrosion of Al wirings is not confirmed
at all.
[0223] .smallcircle.: There is partial corrosion of insulating
materials.
[0224] .DELTA.: There is considerable corrosion of insulating
materials.
[0225] .times.: There is marked corrosion of insulating
materials.
[0226] Here, acceptable products are one rated as
".circleincircle." or ".smallcircle." for both of the removability
of deposition on aluminum wirings and the anticorrosiveness for
aluminum wirings. The results are shown in Table 8. TABLE-US-00008
TABLE 8 Wiring Width of 500 nm pH Initial After Standard Test After
Amount Corrosiveness Corrosiveness Standard of Deposition for
Aluminum Deposition for Aluminum Initial Test Change Removability
Wirings Removability Wirings Ex. 2.2 2.1 0.1 .circleincircle.
.circleincircle. .circleincircle. .circleincircle. III-1 Ex. 1.9
1.7 0.2 .circleincircle. .circleincircle. .circleincircle.
.largecircle. III-2 Ex. 1.8 1.7 0.1 .circleincircle.
.circleincircle. .largecircle. .circleincircle. III-3 Comp. 2.1 1.1
1.0 .circleincircle. .largecircle. .circleincircle. .DELTA. Ex.
III-1 Comp. 2.2 1.4 0.8 .largecircle. .largecircle. .largecircle.
.DELTA. Ex. III-2 Comp. 1.8 1.1 0.9 .circleincircle. .DELTA.
.largecircle. .DELTA. Ex. III-3 Wiring Width of 180 nm Initial
After Standard Test Corrosiveness Corrosiveness Deposition for
Aluminum Deposition for Aluminum Removability Wirings Removability
Wirings Ex. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. III-1 Ex. .circleincircle. .largecircle.
.largecircle. .largecircle. III-2 Ex. .circleincircle.
.circleincircle. .largecircle. .largecircle. III-3 Comp.
.circleincircle. .DELTA. .circleincircle. X Ex. III-1 Comp.
.circleincircle. .DELTA. .circleincircle. X Ex. III-2 Comp.
.circleincircle. .DELTA. .circleincircle. X Ex. III-3
[0227] It can be seen from the results in Table 8 that, in the
cleaning methods using the remover compositions obtained in
Examples III-1 to III-3, sufficient deposition removability and
anticorrosiveness are retained after the standard tests which
involve aluminum oxide dissolution simulating a continuous
cleaning, and in particular, the corrosiveness is not lowered even
for wirings having such a narrow wiring width as 180 nm, as
compared with the methods using one obtained in Comparative
Examples III-1 to III-3.
INDUSTRIAL APPLICABILITY
[0228] In the present invention, the removal cleaning method of
Embodiment 1 described above provides excellent removability of
deposition on aluminum wirings produced during the formation of
semiconductor device and titanium-based deposition on the bottom of
via holes, and also excellent anticorrosiveness without causing
etching of the materials of metal wirings having a narrow wiring
width. Therefore, by using the removal cleaning method of
Embodiment 1 described above, there are exhibited effects that
higher-speed and higher integration in semiconductor devices can be
realized, and that high quality electronic parts such as LCDs,
memories and CPUs can be produced.
[0229] Also, when deposition on aluminum wirings produced during
formation of semiconductor device and titanium-based deposition on
the bottom of via holes are removed using the remover composition
of Embodiment 2 described above, there is exhibited an effect that
contaminations which largely affect the quality of semiconductor,
such as electric properties, can be prevented.
[0230] Also, by using the remover composition of Embodiment 3
described above in a step of removal cleaning semiconductor for
removing deposition on aluminum wirings produced during formation
of semiconductor device and titanium-based deposition on the bottom
of via holes, there can be prevented remaining deposition and
corrosion of wirings, which largely affect the quality of
semiconductor. Also, semiconductors can be continuously cleaned for
a long period of time, without adding or replacing with a fresh
remover, so that there is an effect that the productivity for
semiconductor is increased and high-performance electronic parts
such as LCDs, memories and CPUs can be economically produced.
[0231] Therefore, the removal cleaning method of the present
invention can be applied to the production of even higher-speed,
even more highly integrated and high quality electronic parts such
as LCDs, memories and CPUs.
[0232] Also, the remover composition of the present invention can
be suitably used for production of smaller-sized and
higher-performance electronic parts such as LCDs, memories and
CPUs, and particularly for cleaning a semiconductor substrate or a
semiconductor device having wiring materials containing aluminum
and/or titanium.
[0233] It is apparent that there are many equivalents to the
present invention described above. Such equivalents are not
regarded as departing from the spirit and scope of the invention,
and all the modifications obvious to a person skilled in the art
are within the technical scope of the appended claims.
* * * * *