U.S. patent application number 10/779920 was filed with the patent office on 2004-08-26 for method of cleaning a substrate.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Chung, Dae-Hyuk, Lee, Kwang-Wook, Yeo, In-Joon.
Application Number | 20040163668 10/779920 |
Document ID | / |
Family ID | 32866955 |
Filed Date | 2004-08-26 |
United States Patent
Application |
20040163668 |
Kind Code |
A1 |
Chung, Dae-Hyuk ; et
al. |
August 26, 2004 |
Method of cleaning a substrate
Abstract
To clean contaminants on a substrate including a metal wiring
formed thereon, a cleaning solution including diluted aqueous
sulfuric acid solution is applied onto the substrate. Mega-sonic
energy is applied to the cleaning solution on the substrate. The
contaminants are removed from the substrate in accordance with the
reaction between the diluted aqueous sulfuric acid solution and the
contaminant while the mega-sonic energy is applied to the
substrate. The corrosion of the metal wiring is prevented because
of the cleaning solution including the diluted aqueous sulfuric
acid solution. Additionally, the damage of the substrate is reduced
because the mega-sonic energy is appropriately applied to the
substrate.
Inventors: |
Chung, Dae-Hyuk;
(Sungnam-city, KR) ; Lee, Kwang-Wook;
(Sungnam-city, KR) ; Yeo, In-Joon; (Suwon-city,
KR) |
Correspondence
Address: |
Steven M. Mills
MILLS & ONELLO LLP
Suite 605
Eleven Beacon Street
Boston
MA
02108
US
|
Assignee: |
Samsung Electronics Co.,
Ltd.
|
Family ID: |
32866955 |
Appl. No.: |
10/779920 |
Filed: |
February 17, 2004 |
Current U.S.
Class: |
134/1 ; 134/26;
134/28; 134/3; 134/34; 134/41; 134/6; 257/E21.228 |
Current CPC
Class: |
C11D 11/0047 20130101;
H01L 21/67028 20130101; C11D 7/08 20130101; B08B 3/12 20130101;
H01L 21/02052 20130101; H01L 21/67057 20130101; C23G 1/02 20130101;
C11D 11/007 20130101; H01L 21/67051 20130101 |
Class at
Publication: |
134/001 ;
134/003; 134/006; 134/026; 134/028; 134/034; 134/041 |
International
Class: |
C23G 001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 25, 2003 |
KR |
03-11785 |
Claims
What is claimed is:
1. A method of cleaning a substrate comprising: applying an aqueous
sulfuric acid solution diluted by deionized water onto the
substrate; and cleaning contaminants on the substrate in accordance
with a reaction between the diluted aqueous sulfuric acid solution
with the contaminants by applying a mega-sonic energy to the
substrate including the diluted aqueous sulfuric acid solution.
2. The method of claim 1, wherein the substrate includes a metal
wiring or a metal thin film.
3. The method of claim 1, wherein the diluted aqueous sulfuric acid
solution comprises the deionized water and sulfuric acid by a
volume ratio of about 500:1 to about 8,000:1.
4. The method of claim 3, wherein the sulfuric acid has a
concentration of about 10 ppm to about 1,000 ppm.
5. The method of claim 1, wherein the mega-sonic energy is
generated using a power of about 5 Watts to about 15 Watts.
6. The method of claim 1, wherein cleaning the contaminants is
performed for about 30 seconds to about 120 seconds.
7. The method of claim 6, wherein cleaning the contaminants is
performed at a temperature of about 20 degrees C. to about 30
degrees C.
8. The method of claim 1, wherein cleaning the contaminants is
performed using a spin scrubber.
9. The method of claim 8, wherein the substrate is provided into
the spin scrubber in a batch type, the diluted aqueous sulfuric
solution is applied by a spray process, and the mega-sonic energy
is applied through a bar facing the substrate.
10. The method of claim 8, wherein the substrate rotates at a speed
of about 8 rpm to about 50 rpm.
11. The method of claim 1, further comprising rinsing the substrate
using deionized water, and drying the substrate.
12. A method of cleaning a substrate comprising: providing an
aqueous sulfuric acid solution diluted by deionized water in a
bath; immersing the substrate into the diluted aqueous sulfuric
acid solution; and cleaning contaminants on the substrate in
accordance with a reaction between the diluted aqueous sulfuric
acid solution and the contaminants by applying a mega-sonic energy
to the substrate including the diluted aqueous sulfuric acid
solution.
13. The method of claim 12, wherein the diluted aqueous sulfuric
acid solution comprises the deionized water and sulfuric acid by a
volume ratio of about 500:1 to about 8,000:1.
14. The method of claim 12, wherein the sulfuric acid has a
concentration of about 10 ppm to about 1,000 ppm.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 USC .sctn. 119 to
Korean patent Application 2003-11785, filed on Feb. 25, 2003, the
contents of which are herein incorporated by reference in their
entirety for all purposes.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method of cleaning a
substrate, and more particularly to a method of cleaning a
substrate that includes a metal thin film pattern formed
thereon.
[0004] 2. Description of the Related Art
[0005] Recently, as information processing systems have been widely
utilized, semiconductor devices have been rapidly developed. The
semiconductor devices are required to have improved performance
characteristics such as high response speed as well as large
storage capacity. To meet these requirements, semiconductor
manufacturing technology has been developed so that the
semiconductor devices have high response speed, enhanced
reliability, high integration density, etc.
[0006] As semiconductor manufacturing technology is rapidly
developed, contaminants such as particles or polymers are precisely
controlled in semiconductor manufacturing processes. Though the
contaminants are accurately controlled, various contaminants are
frequently attached on the surface of a semiconductor substrate
during the semiconductor manufacturing process. Hence, cleaning
processes are commonly performed on the semiconductor substrate to
remove the contaminants from the substrate. The cleaning processes
for the semiconductor substrate are generally divided into two
types, namely, a wet cleaning process using a cleaning solution and
a dry cleaning process using a gas.
[0007] As for the wet cleaning process, a semiconductor substrate
is immersed in a cleaning solution including deionized water and/or
a reactive solution after the cleaning solution is deposited in a
bath. Alternatively, the cleaning solution is sprayed onto the
semiconductor substrate to remove the contaminants from the
semiconductor substrate. The cleaning solution typically includes a
hydrochloric acid solution, an aqueous ammonia solution or hydrogen
peroxide solution in addition to the deionized water.
[0008] There is disclosed a method of cleaning a semiconductor
substrate using a cleaning solution including a hydrochloric acid
solution, an aqueous ammonia solution and hydrogen peroxide
solution in Japanese Laid-Open Patent Publication No. 1985-7233 and
Korean Laid-Open Patent Publication No. 2001-56346.
[0009] Additionally, in the wet cleaning process, a magnetic
agitator or mega-sonic energy may be employed to improve the
efficiency of the cleaning process.
[0010] When a semiconductor substrate is cleaned by a wet cleaning
process utilizing the mega-sonic energy, the semiconductor
substrate is cleaned in a bath coupled to a mega-sonic energy
generating member. When the mega-sonic energy is applied to the
semiconductor substrate immersed in a cleaning solution in the
bath, the efficiency of the cleaning process may be improved. The
mega-sonic energy bursts the gas bubbles included in the cleaning
solution to accelerate the cleaning process for the semiconductor
substrate. That is, the gas bubbles formed in the cleaning solution
are ruptured by the mega-sonic energy to generate burst pressure
and temperature variation of the cleaning solution, thereby
removing the contaminants attached to the semiconductor
substrate.
[0011] There are disclosed methods of cleaning a substrate also
utilizing the mega-sonic energy in Korean Patent No. 242,271 and
Japanese Patent Laid-Open Publication No. 1990-257632. When the
substrate is cleaned by such methods using a cleaning solution and
the mega-sonic energy, the contaminants on the substrate may be
effectively removed. However, the substrate may be impaired due to
the mega-sonic energy applied during cleaning the substrate. In
particular, when a metal pattern is formed on the substrate, the
metal pattern may be seriously corroded during cleaning the
substrate by employing those methods.
[0012] Additionally, in the method of cleaning a semiconductor
substrate utilizing the mega-sonic energy, failure of a metal
pattern may occur when the mega-sonic energy applied to the
semiconductor substrate is relatively high. That is, when high
mega-sonic energy is applied to the substrate that includes the
metal pattern, the metal pattern may be broken during cleaning of
the semiconductor substrate.
[0013] Therefore, there is required a method of cleaning a
substrate which reduces the corrosion of the metal patterns formed
on the substrate and minimizes the damage of the substrate or the
metal pattern.
SUMMARY OF THE INVENTION
[0014] In order to overcome above-mentioned problems, a feature of
the present invention is to provide a method of effectively
cleaning a substrate without causing damage to the substrate and
the metal wiring formed on the substrate.
[0015] In accordance with one aspect of the present invention, an
aqueous sulfuric acid solution diluted by deionized water is
applied onto a substrate. Contaminants on the substrate are cleaned
in accordance with the reaction between the diluted aqueous
sulfuric acid solution and the contaminants by applying a
mega-sonic energy to the substrate including the diluted aqueous
sulfuric acid solution.
[0016] The mega-sonic energy can be generated using a power of
about 5 Watts to about 15 Watts. The diluted aqueous sulfuric acid
solution includes the deionized water and sulfuric acid by a volume
ratio of about 500:1 to about 8,000:1, and the sulfuric acid has a
concentration of about 10 ppm to about 1,000 ppm. The substrate is
cleaned at a temperature of about 20 degrees C. to about 30 degrees
C. for about 30 seconds to about 120 seconds.
[0017] The substrate being cleaned may have structures such as a
metal wiring or a metal thin film formed thereon. The aqueous
sulfuric acid solution may be applied while the substrate is
rotated at a speed of about 8 rpm to about 50 rpm.
[0018] In one embodiment, cleaning the substrate is performed using
a spin scrubber. The substrate can be provided in the spin scrubber
in a batch type. The diluted aqueous sulfuric acid solution can be
applied by a spray process, and the mega-sonic energy can be
applied through a bar facing the substrate. In one embodiment, the
substrate is rinsed using deionized water and dried.
[0019] In accordance with another aspect of the present invention,
after an aqueous sulfuric acid solution diluted by deionized water
is provided in a bath, the substrate, which can have a metal wiring
or a metal thin film formed thereon, is immersed into the diluted
aqueous sulfuric acid solution. The contaminants on the substrate
are removed in accordance with the reaction between the diluted
aqueous sulfuric acid solution and the contaminants by applying
mega-sonic energy to the substrate including the diluted aqueous
sulfuric acid solution.
[0020] According to the present invention, the contaminants on a
substrate can be effectively removed and the metal wiring formed on
the substrate is not corroded when a cleaning solution includes a
diluted aqueous sulfuric acid solution and mega-sonic energy is
applied to the substrate during a cleaning process. Thus, a
reliability of a semiconductor device may be improved and the
throughput of a semiconductor manufacturing process may be
enhanced. Additionally, appropriate mega-sonic energy is applied to
the substrate in the cleaning process so that the failure of the
metal wiring such as a short may be prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The foregoing and other objects, features and advantages of
the invention will be apparent from the more particular description
of a preferred embodiment of the invention, as illustrated in the
accompanying drawings in which like reference characters refer to
the same parts throughout the different views. The drawings are not
necessarily to scale, emphasis instead being placed upon
illustrating the principles of the invention.
[0022] FIG. 1 is a schematic cross-sectional view illustrating a
spin scrubber employed for performing a method of cleaning a
substrate according to one embodiment of the invention.
[0023] FIG. 2 is a schematic cross-sectional view illustrating a
bath employed for performing a method of cleaning a substrate
according to another embodiment of the invention.
[0024] FIG. 3 is a flow chart illustrating the method of cleaning a
substrate according to one embodiment of the invention.
[0025] FIG. 4 is a flow chart illustrating the method of cleaning a
substrate according to another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] The cleaning solution that can be used in the present
invention includes an aqueous sulfuric acid solution diluted by
deionized water. When sulfuric acid diluted in the diluted aqueous
sulfuric acid solution has a concentration of below about 10 ppm,
the efficiency of a cleaning process that is performed on the
substrate using the diluted aqueous sulfuric acid solution may be
reduced. Also, the substrate, especially the metal wiring formed on
the substrate, may be damaged during the cleaning process using the
diluted aqueous sulfuric acid solution when the sulfuric acid
diluted in the diluted aqueous sulfuric acid solution has a
concentration of above about 1,000 ppm. Therefore, the sulfuric
acid diluted in the diluted aqueous sulfuric acid solution
preferably has a concentration of about 10 ppm to about 1,000
ppm.
[0027] When the volume ratio between the deionized water and the
sulfuric acid is below about 500:1, the substrate may be impaired
during the cleaning process. However, when the volume ratio between
the deionized water and the sulfuric acid is above about 8,000:1,
the efficiency of the cleaning process for the substrate may be
reduced. Accordingly, in the present invention, in the diluted
aqueous sulfuric acid solution, the volume ratio between the
deionized water and the sulfuric acid is preferably about 500:1 to
about 8,000:1.
[0028] When the diluted aqueous sulfuric acid solution is applied
as a cleaning solution to a substrate including a metal wiring or
metal thon film, the corrosion of the metal wiring may be
effectively prevented. Thus, the cleaning solution including
diluted aqueous sulfuric acid solution is advantageously employed
for the substrate having the metal wiring or the metal thin film
formed thereon.
[0029] The cleaning solution can be provided onto the substrate
using one of at least two processes such as a spray process and an
immersion process.
[0030] FIG. 1 is a schematic cross-sectional view illustrating a
spin scrubber employed for performing a method of cleaning a
substrate according to one embodiment of the present invention.
[0031] To clean a substrate 10 using the spray process, a cleaning
apparatus includes a spin scrubber as shown in FIG. 1. The spin
scrubber is a batch type including a chuck 12 and a nozzle 14.
[0032] The substrate 10 including the metal wiring is loaded on the
chuck 12, and the cleaning solution is provided onto the substrate
10 from the nozzle 14. That is, the cleaning solution is applied
onto the substrate 10 by a spray process using the nozzle 14.
[0033] When the cleaning process is performed on the substrate 10,
the cleaning solution is sprayed onto the substrate 10 through the
nozzle 14 while the substrate 10 is rotated in accordance with the
rotation of the chuck 12. When the rotation speed of the substrate
10 is below about 8 rpm, the cleaning solution may not be uniformly
sprayed onto the substrate 10 from the nozzle 14. That is, the
cleaning solution may not reach to the peripheral portion of the
substrate 10 because the centrifugal force caused by the rotation
of the substrate 10 is relatively weak. When the rotation speed of
the substrate 10 is above about 50 rpm, the cleaning solution may
be rapidly splashed from the surface of the substrate 10. That is,
since the centrifugal force caused by the rotation of the substrate
10 is too high, the cleaning solution may splash from the substrate
10. Thus, the rotation speed of the substrate 10 is preferably
about 8 rpm to about 50 rpm.
[0034] In addition, a mega-sonic energy generating construction is
provided in order to apply mega-sonic energy to the substrate 10
where the cleaning solution is sprayed during the cleaning process.
For this reason, the spin scrubber further includes a mega-sonic
energy transmitting member 16 that applies the mega-sonic energy to
the substrate 10 including the cleaning solution sprayed
thereon.
[0035] The mega-sonic energy transmitting member 16 includes a
power generating section 16b and a bar 16a extended toward the
substrate 10 from the power generating section 16b. The power
generating section 16b generates the mega-sonic energy and the bar
16a applies the mega-sonic energy to the cleaning solution sprayed
on the substrate 10. The bar 16a faces the surface of the substrate
10.
[0036] When the mega-sonic energy applied to cleaning solution
sprayed on the substrate 10 is weak, the efficiency of the cleaning
process may not be effective. However, when the mega-sonic energy
applied to the cleaning solution from the mega-sonic transmitting
member 16 is too high, the substrate 10 may be damaged during the
cleaning process. Hence, the mega-sonic energy transmitting member
16 applies appropriate mega-sonic energy to the substrate 10
including the cleaning solution sprayed thereon. The amount of the
mega-sonic energy is can be substantially determined in accordance
with the power generated from the power generating section 16b.
Preferably, the power generating section 16b generates a power of
about 5 Watts to about 15 Watts in order to apply the appropriate
mega-sonic energy to the substrate 10. The cleaning process is
preferably performed at a temperature of about 20 degrees C. to
about 30 degrees C. for about 30 seconds to about 120 seconds.
[0037] The cleaning mechanism using the cleaning solution and the
mega-sonic energy will be described.
[0038] When the cleaning solution is sprayed on the substrate 10,
the cleaning solution is applied as a thin film having a
predetermined thickness in accordance with the rotation of the
substrate 10. Then, the mega-sonic energy is applied to the
cleaning solution sprayed on the substrate 10. As the diluted
aqueous sulfuric acid solution of the cleaning solution is
chemically reacted with the contaminants formed on the substrate
10, the contaminants such as polymers or particles are removed from
the substrate 10 according to the chemical reaction between the
diluted aqueous sulfuric acid solution and the contaminants.
Additionally, the gas bubbles included in the cleaning solution are
burst by applying the mega-sonic energy to the cleaning solution.
The rupture of the gas bubbles in the cleaning solution provides
bursting pressure and changes the temperature of the cleaning
solution, thereby facilitating the physical reaction between the
cleaning solution and the contaminants. As a result, any
contaminants existing on the substrate 10 are more effectively
removed from the substrate 10.
[0039] After the contaminants on the substrate 10 are removed from
the substrate 10 by using the scrubber and the cleaning solution,
the substrate 10 is rinsed using deionized water. Then, the rinsed
substrate 10 is dried to remove the moisture or water drops on the
substrate 10. Here, the moisture or water drops on the substrate 10
are removed by a dry process using a nitrogen gas or by a wet
process using isopropyl alcohol.
[0040] As described above, the efficiency of the cleaning process
performed using the spin scrubber can be improved by spraying the
cleaning solution on the substrate and by applying the mega-sonic
energy to the cleaning solution. Particularly, since the cleaning
solution includes the diluted aqueous sulfuric acid solution, the
efficiency of the cleaning solution can be more improved. Further,
the damage of the substrate can be reduced during the cleaning
process because the appropriate mega-sonic energy is advantageously
applied to the substrate 10.
[0041] The immersion process for cleaning the substrate will be
described.
[0042] FIG. 2 is a schematic cross-sectional view illustrating a
bath employed for performing a method of cleaning a substrate
according to another embodiment of the invention
[0043] Referring to FIG. 2, a cleaning apparatus includes a bath 22
to perform the immersion process for cleaning a substrate 20
including a metal wiring or metal thin film formed thereon. A
cleaning solution is received in the bath 22, and the substrate 20
is immersed into the cleaning solution.
[0044] As described above, a mega-sonic energy transmitting member
26 is connected to the bath 22 to apply mega-sonic energy to the
substrate 20 immersed in the cleaning solution. The mega-sonic
energy transmitting member 26 includes a power generating section
26b and a bar 26a. The power generating section 26b generates the
mega-sonic energy, and the bar 26a applies the mega-sonic energy to
the substrate 20 immersed in the cleaning solution. Here, the bar
26a of the mega-sonic energy transmitting member 26 is positioned
at the lower portion of the bath 22 under the substrate 20 having
the metal wiring. The mega-sonic energy generated from the power
generating section 26b is applied to the substrate 20 through the
bar 26a. As described above, appropriate mega-sonic energy may be
applied to the substrate 20. Thus, the power generating section 26b
has a power of about 5 Watts to about 15 Watts to generate the
appropriate mega-sonic energy. Preferably, the cleaning process is
performed on the substrate 20 having the metal wiring at a
temperature of about 20 degrees C. to about 30 degrees C. for about
30 seconds to about 120 seconds.
[0045] After contaminants on the substrate 20 are removed from the
substrate 20 using the cleaning solution received in the bath 22,
the substrate 20 is rinsed and dried as described above.
[0046] FIG. 3 is a flow chart illustrating a method of cleaning a
substrate according to one embodiment of the invention.
[0047] Referring to FIGS. 1 and 3, in step S31, the substrate 10
including a metal wiring or a thin metal film is loaded on the
chuck 12. The substrate 10 is rotated by predetermined rotation
speed using the chuck 12 in step S33. In step S35, a cleaning
solution including a diluted aqueous sulfuric acid solution is
sprayed onto the rotating substrate 10 having the metal wiring.
Here, the cleaning solution is provided around the central portion
of the substrate 10. Because the substrate 10 rotates during
spraying of the cleaning solution, the cleaning solution is
uniformly dispersed from the central portion of the substrate 10 to
the peripheral portion of the substrate 10. Thus, the cleaning
solution is sprayed on the substrate 10 as a film. Contaminants,
for example, particles or polymers, existing on the substrate 10
are primarily removed by spraying the cleaning solution. That is,
the contaminants are removed from the substrate 10 in accordance
with the chemical reaction between the cleaning solution and the
contaminants.
[0048] Then, a mega-sonic energy transmitting member 16 applies
mega-sonic energy to the substrate 10 where the cleaning solution
is sprayed. The gas bubbles included in the cleaning solution are
burst by the mega-sonic energy to provide bursting pressure and the
variation of a temperature. Hence, the contaminants on the
substrate 10 are secondarily removed from the substrate 10 by the
bursting pressure and the variation of the temperature caused by
the rupture of the gas bubbles.
[0049] After the substrate 10 is rinsed in step S39, the rinsed
substrate 10 is dried in step S41.
[0050] FIG. 4 is a flow chart illustrating the method of cleaning a
substrate according to another embodiment of the present
invention.
[0051] Referring to FIGS. 2 and 4, a cleaning solution including a
diluted aqueous sulfuric acid solution is received in the bath 22
in step S51. In step S53, the substrate 20 having a metal wiring or
a metal thin film is immersed into the cleaning solution received
in the bath 22. In addition, mega-sonic energy is applied to the
substrate 20 from a mega-sonic energy generating member 26. Thus,
contaminants existing on the substrate 20 are removed by the
cleaning solution and the mega-sonic energy. In this case, the
contaminants on the substrate 20 are chemically removed by the
cleaning solution, and also physically removed by bursting pressure
and the temperature variation of the cleaning solution. The
bursting pressure and the temperature variation of the cleaning
solution are generated from the rupture of the gas bubbles included
in the cleaning solution.
[0052] The substrate 20 is rinsed in step S55, and then is dried in
step S57.
[0053] As described above, the efficiency of the cleaning process
can be improved because of the cleaning solution including the
diluted aqueous sulfuric acid solution and the mega-sonic energy.
Additionally, since the appropriate mega-sonic energy is applied to
the substrate, the substrate may not be damaged during cleaning the
substrate.
[0054] Hereinafter, an example and comparative examples of the
invention will be described.
EXAMPLE
[0055] A diluted aqueous sulfuric acid solution was prepared as a
cleaning solution for a substrate having a metal thin film formed
thereon. Here, the volume ratio between sulfuric acid and deionized
water in the diluted aqueous sulfuric acid solution was about
1:1,000. The substrate was cleaned with the diluted aqueous
sulfuric acid solution using a spin scrubber. The cleaning process
was performed on the substrate at a temperature of about 30 degrees
C. for about 30 seconds. The substrate was rotated by a rotation
speed of about 30 rpm during the cleaning process. Additionally,
mega-sonic energy generated using a power of about 14 Watts was
applied to the substrate on which the diluted aqueous sulfuric acid
solution was sprayed. As a result, the contaminants existing on the
substrate were removed by about 60 percent without corrosion of the
metal thin film formed on the substrate.
Comparative Example 1
[0056] A substrate was cleaned according to the above-described
process except for the type of cleaning solution. In this case, the
cleaning solution included deionized water only.
[0057] Though the metal thin film formed on the substrate was not
corroded, the contaminants on the substrate were minutely removed
by about 2 percent.
Comparative Example 2
[0058] A substrate was cleaned according to the above-described
process except a cleaning solution including hot deionized water
only.
[0059] The metal thin film formed on the substrate was seriously
corroded as well as the contaminants existing on the substrate were
slightly removed by about 10 percent.
Comparative Example 3
[0060] A substrate was cleaned according to the above-described
process except for the type of cleaning solution. The cleaning
solution included an aqueous ammonia solution and deionized water
by a volume ratio of about 1:1,000.
[0061] The metal thin film formed on the substrate was seriously
corroded although the contaminants existing on the substrate were
removed by about 68 percent.
[0062] As a result, when the substrate is cleaned using the
cleaning solution including the diluted aqueous sulfuric acid
solution, the contaminants on the substrate are effectively removed
from the substrate while the metal thin film on the substrate is
not corroded.
[0063] As described above, the contaminants on a substrate can be
effectively removed and the metal wiring formed on the substrate is
not corroded when a cleaning solution includes a diluted aqueous
sulfuric acid solution and mega-sonic energy is applied to the
substrate during a cleaning process. Thus, a reliability of a
semiconductor device may be improved and the throughput of a
semiconductor manufacturing process may be enhanced.
[0064] Additionally, appropriate mega-sonic energy is applied to
the substrate in the cleaning process so that the failure of the
metal wiring such as a short may be prevented. While this invention
has been particularly shown and described with reference to
preferred embodiments thereof, it will be understood by those
skilled in the art that various changes in form and details may be
made therein without departing from the spirit and scope of the
invention as defined by the appended claims.
* * * * *