JP3605248B2 - Substrate processing equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for cleaning various substrates such as a semiconductor wafer, a glass substrate for a liquid crystal display device, and a PDP (plasma display panel) substrate.
[0002]
[Prior art]
The manufacturing process of a semiconductor device includes a process of forming a fine pattern by repeatedly performing processes such as film formation and etching on the surface of a semiconductor wafer (hereinafter, simply referred to as “wafer”). Since the surface of the wafer itself and the surface of the thin film formed on the wafer surface need to be kept clean for microfabrication, the wafer is cleaned as necessary. For example, after a wafer or a thin film formed on the surface thereof is polished with an abrasive, the abrasive (slurry) remains on the wafer surface, and it is necessary to remove the abrasive.
[0003]
FIGS. 7 and 8 show a conceptual configuration of the related art for cleaning a wafer as described above. That is, the wafer W is supported by the end faces of the wafer W being sandwiched by the pair of end face support hands 210 and 211. A scrub cleaning member 214 composed of a disk-shaped base portion 212 and a cleaning brush 213 fixed to the lower surface of the wafer W is rotated on a contact surface 218 by a rotation drive mechanism (not shown). When the cleaning brush 213 contacts the wafer W, scrub cleaning is performed. Similarly, on the lower surface of the wafer W, a scrub cleaning member 217 composed of a disk-shaped base portion 215 and a cleaning brush 216 fixed on the upper surface thereof is rotated by a rotation driving mechanism (not shown) to form a contact surface. At 219, the scrub cleaning is performed by the cleaning brush 216 contacting the wafer W. Here, the above-mentioned cleaning brushes 213 and 216 are made of, for example, PVA (poly-vinyl alcohol).
[0004]
In this configuration, while holding the wafer W, the end surface support hands 210 and 211 move the wafer W in a circular motion so that the center OW of the wafer W follows a circular orbit as shown in FIG. As a result, since the contact surfaces 218 and 219 come into contact with almost the entire surface of the wafer W, scrub cleaning can be performed on almost the entire surface of the wafer W.
In the scrub cleaning member 214 for scrub cleaning the upper surface of the wafer W, the cleaning brush 213 is fixed in a circular shape over substantially the entire surface of the base portion 212, for example, as shown in FIG. A nozzle 220 is disposed substantially at the center of the cleaning brush 213, and the cleaning liquid is discharged from the nozzle 220. Further, since the contact surface 218 is a flat surface as shown in FIG. 8, the cleaning brush 213 makes surface contact with the upper surface of the wafer W. The scrub cleaning member 217 for scrubbing the lower surface of the wafer W has the same configuration.
[0005]
[Problems to be solved by the invention]
However, in the configuration of the related art, the wafer W is sandwiched by the pair of end face support hands 210 and 211, and the holding position of the end face support hands 210 and 211 with respect to the wafer W is always constant. Therefore, when cleaning the peripheral portion of the wafer W around the holding position, the cleaning brushes 213 and 216 cannot enter the peripheral portion of the wafer W, so that the entire peripheral portion of the wafer W can be cleaned. This makes it impossible and causes a problem that the slurry remains on the peripheral portion of the wafer W. In this case, since the slurry becomes particles, it leads to a decrease in yield in the manufacturing process of the semiconductor device, which has been a serious problem.
[0006]
Furthermore, when the peripheral edge of the wafer W is to be cleaned, the cleaning brushes 213 and 216 of the scrub cleaning members 214 and 217 interfere with the end face supporting hands 210 and 211, and the cleaning brushes 213 and 216 It is damaged and significantly reduces the life of the cleaning brushes 213 and 216.
Therefore, an object of the present invention is to solve the above-mentioned technical problems, to provide a substrate processing apparatus capable of satisfactorily removing foreign matters in the entire peripheral portion of the substrate, and to further improve the life of a cleaning brush for cleaning the substrate. That is.
[0007]
Means for Solving the Problems and Effects of the Invention
According to the first aspect of the present invention, there is provided a holding roller for holding a substrate in contact with at least three places on an end face of the substrate, and at least one of the holding rollers for the substrate. Holding means having a roller driving means for rotating around a substantially vertical axis, a cleaning liquid supply means for supplying a cleaning liquid to the substrate held by the substrate holding means, and a cleaning liquid supply connected to the cleaning liquid supply means A nozzle cleaning means for cleaning at least a peripheral portion of the substrate held by the substrate holding means, wherein the substrate cleaning means is substantially rotated with respect to the substrate held by the substrate holding means by rotation driving means. A scrub cleaning member having a base rotated around a vertical axis and a brush fixed to the base and in contact with the surface of the substrate. The cleaning liquid supply nozzle is disposed near the center of the brush portion of the scrub cleaning member, and the brush portion of the scrub cleaning member is provided with a first brush portion disposed substantially at the center of the base portion. And a second brush portion disposed around the first brush portion. The first brush portion spreads the cleaning liquid discharged from the cleaning liquid supply nozzle toward the peripheral edge of the substrate. A substrate processing apparatus, wherein a groove is formed along a direction from the cleaning liquid supply nozzle toward the second brush portion .
[0008]
According to the present invention, the holding roller for holding the end surface of the substrate is rotated by the roller driving means, whereby the substrate rotates with respect to the substrate holding means, and the contact portion where the substrate abuts on the holding roller is always Therefore, it is possible to provide a substrate processing apparatus capable of satisfactorily removing foreign substances on the peripheral portion of the substrate by the substrate cleaning means .
[0009]
Further, according to the present invention, the brush portion of the scrub cleaning member for cleaning the substrate can satisfactorily remove foreign matters from the peripheral portion of the substrate without interfering with the holding roller, thereby improving the life of the brush portion. Can be .
According to a second aspect of the invention, the rotary drive means, according to claim 1, wherein the the substrate is rotated is held by the substrate holding means is for rotating the base portion in the opposite direction It is a substrate processing apparatus .
According to a third aspect of the invention, the brush portion of the scrubbing member, according to claim 1, wherein a in which is disposed so as to cover the region leading to the periphery from the center of the substrate It is a substrate processing apparatus.
[0010]
According to the present invention, the brush portion of the scrub cleaning member is rotated while being in contact with the surface of the substrate in a region from the center portion to the peripheral portion of the substrate, and the contact portion of the substrate is constantly changed by the holding roller. It is rotated while doing. Therefore, it is possible to provide a substrate processing apparatus capable of satisfactorily removing foreign substances from the entire surface of the substrate including the peripheral portion of the substrate.
[0011]
Invention of claim 4, further comprising a pair of the scrubbing member, the pair of scrub cleaning member is disposed opposite so as to sandwich the substrate held by the substrate holding means from above and below, the upper surface of the substrate and a substrate processing apparatus according to any one of claims 1 to 3, wherein the lower surface of the one in which scrubbing.
According to the present invention, since the scrub cleaning members are disposed to face each other so as to scrub the upper and lower surfaces of the substrate, the substrate processing apparatus can satisfactorily remove foreign substances from the entire upper and lower surfaces of the substrate including the peripheral portion of the substrate. Can be provided.
According to a fifth aspect of the present invention, in the substrate processing apparatus according to any one of the first to fourth aspects, the brush portion of the scrub cleaning member is arranged in a cross shape on the base portion. is there.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a plan view showing a configuration of a wafer cleaning apparatus which is a substrate processing apparatus according to one embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1, with some parts omitted and some parts conceptually shown.
[0013]
This apparatus has a substantially rectangular processing chamber 5 in a plan view surrounded by side walls 1, 2, 3, and 4, holds the wafer W horizontally in the processing chamber 5, and rotates the wafer W in this state. And a double-side cleaning for scrubbing the upper and lower surfaces of the wafer W by supplying cleaning liquid from the cleaning liquid supply nozzles 7 and 8 to the upper and lower surfaces of the wafer W held by the wafer holding device 6. Device 9.
[0014]
The wafer holding device 6 includes a pair of holding hands 10 and 30 that are opposed to each other in a direction A (hereinafter, referred to as a “holding direction”) orthogonal to the side wall 2 or 4 of the processing chamber 5. The holding hands 10 and 30 are movable in the holding direction A, and are disposed above the bases 12 and 32 attached to the base attachments 11 and 31 and the bases 12 and 32, respectively. It has three holding rollers 13 and 33 for holding, respectively. These holding rollers 13 and 33 are arranged on a circumference corresponding to the shape of the end face of the wafer W. The wafer W is held in a state where the end surfaces thereof are in contact with the side surfaces of the holding rollers 13 and 33.
[0015]
One end of each of hand shafts 15 and 35 formed in base mounting portions 11 and 31 along the holding direction A and extending to the outside of side walls 2 and 4 via holes 14 and 34 formed in side walls 2 and 4. Are connected. Rods 18, 38 of cylinders 17, 37 fixed on mounting plates 16, 36 outside the side walls 2, 4 are attached to the other ends of the hand shafts 15, 35 via connecting plates 19, 39. . The rods 18 and 38 can be protruded or retracted along the holding direction A. With this configuration, by driving the cylinders 17 and 37, the holding hands 10 and 30 can be moved back and forth in the opposite directions along the holding direction A, and the wafer W is held between the holding rollers 13 and 33. Or release the pinch.
[0016]
Reference numerals 20 and 40 denote bellows that can expand and contract with the movement of the holding hands 10 and 30. The cleaning liquid supplied to the wafer W from the cleaning liquid supply nozzles 7 and 8 of the double-sided cleaning device 9 and the atmosphere thereof are hand This is to prevent the shafts 15 and 35 from being affected or to prevent leakage to the outside of the processing chamber 5. Further, it is for preventing particles generated from the rods 18 and 38 of the cylinders 17 and 37 and the hand shafts 15 and 35 from entering the inside of the processing chamber 5.
[0017]
The holding rollers 13 and 33 are rotatably provided on the base portions 12 and 32 so as to rotate the wafer W while holding the wafer W. That is, the holding rollers 13 and 33 are fixed to roller shafts 21 and 41 supported by the base portions 12 and 32 so as to be rotatable around a vertical axis.
The driving force required to rotate the wafer W is applied only to the holding roller 33. In other words, the driving force of the motor M attached to the motor attachment plate 42 provided outside the side wall 2 is transmitted to the central holding roller 33 b of the holding rollers 33 via the belt 43. ing. Further, the driving force transmitted to the central holding roller 33b is also transmitted to the other two holding rollers 33a and 33c via the belts 44 and 45.
[0018]
Further details will be described. As shown in FIG. 3, the roller shaft 41a of the holding roller 33a extends through a through hole 46a formed in the base 32 to a space 47 formed near the lower end of the base 32. It is rotatably supported by the base 32 via two bearings 47a and 48a arranged in the insertion hole 46a. Similarly, the roller shafts 41b and 41c of the other two holding rollers 33b and 33c are extended to the space 47 through the insertion holes 46b and 46c, and the two bearings 47b and 41c disposed in the insertion holes 46b and 46c. 48b: rotatably supported by the base portion 32 via 47c and 48c.
[0019]
Three pulleys 49b, 50b, 51b are attached to the central roller shaft 41b. The belt 43 is wound between the uppermost pulley 49b and the pulley 53 (see FIG. 2) attached to the drive shaft 52 of the motor M. The belts 44 and 45 are wound around the remaining two pulleys 50b and 51b and the pulleys 51a and 51c attached to the other two roller shafts 41a and 41c, respectively.
[0020]
With the above configuration, when the central holding roller 33b is driven by the motor M, the other two holding rollers 33a and 33c are driven accordingly. As a result, the wafer W held by the holding rollers 13 and 33 starts rotating. At this time, the holding roller 13 rotates with the rotation of the wafer W. In this way, the wafer W rotates along the rotation direction B while being held by the holding rollers 13 and 33. The rotation speed of wafer W in this case is, for example, about 10 to 20 (rotation / minute).
[0021]
Returning to FIG. 2, the double-sided cleaning device 9 includes an upper surface cleaning unit 60 and a lower surface cleaning unit 80 disposed above and below the wafer W held by the wafer holding device 6. The upper surface cleaning unit 60 and the lower surface cleaning unit 80 are arranged at positions that do not interfere with the holding hands 10 and 30 so as to cover the surface area of the wafer W from the center to the peripheral edge of the wafer W.
[0022]
The upper surface cleaning unit 60 and the lower surface cleaning unit 80 include base portions 62, 82 having mounting surfaces 61, 81 on the side facing the wafer W, and rotating shafts 63, 83 mounted on the base portions 62, 82. The rotation drive units 64 and 84 can rotate around a rotation axis O along the vertical axis in a rotation direction C (a rotation direction opposite to the rotation direction B of the wafer W) .
Further, the upper surface cleaning unit 60 and the lower surface cleaning unit 80 can be moved in the vertical direction by the elevation drive units 65 and 85, respectively. Thereby, the wafer W can be sandwiched between the upper surface cleaning unit 60 and the lower surface cleaning unit 80 during the wafer cleaning, and the upper surface cleaning unit 60 and the lower surface cleaning unit 80 can be separated from the wafer W after the wafer cleaning. I can do it.
[0023]
Cleaning brushes 66 and 86 are provided on the mounting surfaces 61 and 81 of the upper base 62 and the lower base 82. In the vicinity of the center of the cleaning brushes 66, 86, cleaning liquid supply nozzles 7, 8 for supplying a cleaning liquid to the wafer W are arranged, respectively. Cleaning pipes 67 and 87 are connected to the cleaning liquid supply nozzles 7 and 8. The cleaning pipes 67 and 87 are inserted into the rotating shafts 63 and 83 so as not to rotate, and the other ends are connected to the other ends through three-way valves 68 and 88, such as hydrofluoric acid, nitric acid, hydrochloric acid, phosphoric acid, acetic acid, Chemical solution supply paths 69 and 89 through which a chemical such as ammonia is guided from a chemical tank (not shown) and pure water supply paths 70 and 90 through which pure water is guided from a pure water tank (not shown) are connected. With this configuration, by controlling the switching of the three-way valves 68 and 88, the chemical solution and pure water can be selectively supplied to the cleaning pipes 67 and 87. Therefore, the chemical solution and pure water can be selectively supplied from the cleaning solution supply nozzles 7 and 8. Can be discharged.
[0024]
The cleaning brushes 66 and 86 have the same configuration. Therefore, hereinafter, the cleaning brush 66 will be described as an example. The cleaning brush 66 is made of, for example, PVA (poly-vinyl alcohol), and is arranged in a cross shape on the mounting surface 61 of the base 62 having a circular shape, as shown in FIG. More specifically, the cleaning brush 66 is disposed substantially at the center of the mounting surface 61 and has a substantially circular first brush portion 71 in plan view, and is formed to be long along the radial direction of the mounting surface 61, and It is configured to be separated into four second brush parts 72 which are arranged around the brush part 70 by being shifted by approximately 90 degrees along the circumferential direction of the mounting surface 61.
[0025]
At the center of the first brush 71, a substantially circular concave portion 73 is formed in a plan view. The cleaning liquid supply nozzle 7 for supplying the cleaning liquid to the wafer W is provided so as to pass through the bottom surface of the concave portion 73. Four V-grooves 74 are formed around the concave portion 73 for spreading the cleaning liquid discharged from the cleaning liquid supply nozzle 7 toward the peripheral portion of the wafer W. As shown in FIG. 4, the four V grooves 74 are formed along the direction from the cleaning liquid supply nozzle 7 to the four second brush portions 72.
[0026]
As shown in the cross section of FIG. 5, the second brush portion 72 has a mountain-shaped cross section with the vertex on the side that contacts the wafer W. That is, the second brush portion 72 includes a flat plate portion 72a and a triangular prism-shaped convex portion 72b integrally formed with the flat plate portion 72a and lying on the flat plate portion 72a. More specifically, the convex portion 72b has a pair of inclined surfaces 72c rising from the flat plate portion 72a and a ridge portion formed where the inclined surfaces 72c meet, and the ridge portion is formed on the surface of the wafer W. 72d. Therefore, the second brush portion 72 is substantially in line contact with the surface of the wafer W.
[0027]
FIG. 6 is a block diagram showing an electrical configuration of the wafer cleaning apparatus. The wafer cleaning apparatus includes a control unit 100 including a microcomputer functioning as a control center. The control unit 100 controls the cylinders 17 and 37, the motor M, the rotary drive units 64 and 84, the elevation drive units 65 and 85, and the three-way valves 68 and 88 according to a preset program.
[0028]
Next, an operation for scrub cleaning the wafer W will be described. Before cleaning, the holding hands 10 and 30 stand by at a standby position retracted from the holding position for holding the wafer W, and the upper surface cleaning unit 60 and the lower surface cleaning unit 80 also stand by at a distance from the wafer W. . When the wafer W is transferred by the transfer arm (not shown) after the previous process is completed, the control unit 100 causes the rods 18 and 38 of the cylinders 17 and 37 to retract. As a result, the holding hands 10, 30 approach each other. As a result, the wafer W is held by the holding rollers 13 and 33 on the end surface.
[0029]
Thereafter, the control unit 100 drives the rotation driving units 64 and 84 to rotate the upper surface cleaning unit 60 and the lower surface cleaning unit 80. At the same time, the control unit 100 controls the three-way valves 68 and 88 to connect the chemical supply paths 69 and 89 and the cleaning pipes 67 and 87. As a result, the chemical liquid is supplied from the cleaning liquid supply nozzles 7 and 8 to the upper and lower surfaces of the wafer W, respectively.
[0030]
After that, the control unit 100 drives the motor M. As a result, the holding roller 33 is driven to rotate. Along with this, the wafer W rotates at a low speed. Further, the control unit 100 controls the elevation drive units 65 and 85 to move the upper surface cleaning unit 60 and the lower surface cleaning unit 80 in directions approaching each other. As a result, the wafer W held by the holding rollers 13 and 33 is sandwiched by the cleaning brushes 66 and 86, and the upper and lower surfaces of the wafer W are rubbed by the cleaning brushes 66 and 86.
[0031]
As a result, the upper and lower surfaces of the wafer W are scrub-cleaned by the cleaning brushes 66 and 86 while the chemical solution is supplied. In this case, the upper surface cleaning unit 60 and the lower surface cleaning unit 80 are arranged so as to cover the surface area of the wafer W from the center to the peripheral edge of the wafer W, and the wafer W is also rotated at a low speed. The entire upper and lower surfaces of W are scrub-cleaned.
[0032]
By the way, at the time of this scrub cleaning, the contact portion 72d of the second brush portion 72 of the cleaning brush 66 is substantially in line contact with the upper surface of the wafer W. Therefore, the slurry removed from the upper surface of the wafer W as a result of the scrub cleaning is pushed by the side surface portion 72c of the convex portion 72b of the second brush portion 72 without being captured by the cleaning brush 66, and the cleaning brush 66 is removed. The wafer W is swept out of the wafer W by the centrifugal force generated by the rotational force.
[0033]
Since the contact portion of the second brush portion of the cleaning brush 86 is substantially in linear contact with the lower surface of the wafer W, the same can be said for the lower surface of the wafer W. When the scrub cleaning with the chemical solution is completed, the control unit 100 controls the elevation driving units 65 and 85 to move the upper surface cleaning unit 60 and the lower surface cleaning unit 80 away from the wafer W, and the cleaning brush 66 from the wafer W. , 86 away. Then, the three-way valves 68 and 88 are controlled so that the cleaning pipes 67 and 87 and the pure water supply paths 70 and 90 are connected. As a result, pure water is supplied from the cleaning liquid supply nozzles 7 and 8, and the chemical liquid remaining on the upper and lower surfaces of the wafer W is washed away.
[0034]
When pure water is supplied in the next step, it is not necessary to supply pure water from the cleaning liquid supply nozzles 7 and 8.
As described above, according to the present embodiment, the holding rollers 13, 33 for holding the end surfaces of the wafer W are rotated by the motor M, so that the wafer W rotates with respect to the wafer holding device 6, and the wafer W is moved. The contact portions that contact the holding rollers 13 and 33 always change. Further, the cleaning brushes 66 and 86 of the double-sided cleaning device 9 are rotated while being in contact with the surface of the wafer W in a region from the center to the peripheral edge of the wafer W. Further, the double-sided cleaning device 9 disposed opposite to the wafer W with scrubbing cleans the upper and lower surfaces of the wafer W. Therefore, from the above, foreign substances on the entire upper surface and lower surface of the wafer W including the peripheral portion of the wafer W can be favorably removed.
[0035]
Further, the cleaning brushes 66 and 86 of the double-sided cleaning device 9 for cleaning the wafer W can remove foreign matters from the peripheral portion of the wafer W without interference with the holding rollers 13 and 33. The service life of 66 and 86 can be improved. The description of one embodiment of the present invention is as described above, but the present invention is not limited to the above embodiment. For example, in the above embodiment, the case where the wafer W is cleaned is described. However, the present invention is applicable to cleaning various other substrates such as a glass substrate for a liquid crystal display device and a PDP (plasma display panel) substrate. It can be widely applied to
[0036]
In addition, various design changes can be made within the scope of the technical matters described in the claims.
[Brief description of the drawings]
FIG. 1 is a plan view illustrating a configuration of a wafer cleaning apparatus that is a substrate processing apparatus according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1, partially omitted and conceptually illustrated;
FIG. 3 is a diagram for explaining a driving mechanism of a holding roller.
FIG. 4 is a diagram showing a configuration of a cleaning brush.
FIG. 5 is a view showing a cross-sectional shape of a second brush portion of the cleaning brush.
FIG. 6 is a block diagram illustrating an electrical configuration of the wafer cleaning apparatus.
FIG. 7 is a conceptual diagram of the configuration of a conventional device as viewed from above.
FIG. 8 is a conceptual view of the configuration of a conventional device as viewed from the side.
FIG. 9 is a view showing a configuration of a conventional cleaning brush.
[Explanation of symbols]
6. Wafer holding device (substrate holding means)
7, 8 Cleaning liquid supply nozzle 9 Double-sided cleaning device (substrate cleaning means)
10, 30 Holding hands 13, 33 Holding rollers 43, 44, 45 Belt 60 Upper surface cleaning unit 80 Lower surface cleaning unit 61, 81 Mounting surface 62, 82 Base unit 64, 84 Rotation drive unit (rotation drive unit)
65,85 Lifting drive unit 66,86 Cleaning brush (brush unit)
67,87 Cleaning pipe (cleaning liquid supply means)
68, 88 Three-way valve 69, 89 Chemical solution supply path 70, 90 Pure water supply path 72 Second brush part 72b Convex part 72d Contact part 100 Control unit M Motor (roller driving means)
W wafer

Claims (5)

A substrate having a holding roller for holding a substrate in contact with at least three places on an end surface of the substrate, and a roller driving means for rotating at least one of the holding rollers about an axis substantially perpendicular to the substrate. Holding means;
Cleaning liquid supply means for supplying a cleaning liquid to the substrate held by the substrate holding means,
A cleaning liquid supply nozzle connected to the cleaning liquid supply means,
Substrate cleaning means for cleaning at least a peripheral portion of the substrate held by the substrate holding means,
The substrate cleaning means is, by a rotation driving means, a base portion which is rotated about an axis substantially perpendicular to the substrate held by the substrate holding means, and is fixed to the base portion, and is fixed to the surface of the substrate. Including a scrub cleaning member having a brush portion that comes into contact with
The cleaning liquid supply nozzle is disposed near the center of the brush portion of the scrub cleaning member,
The brush part of the scrub cleaning member is separated into a first brush part disposed substantially at the center of the base part and a second brush part disposed around the first brush part.
A groove for spreading the cleaning liquid discharged from the cleaning liquid supply nozzle toward the peripheral portion of the substrate is formed in the first brush section along a direction from the cleaning liquid supply nozzle toward the second brush section. A substrate processing apparatus. The rotary drive means, the substrate processing apparatus according to claim 1, wherein the the substrate is rotated is held by the substrate holding means is for rotating the base portion in the opposite direction. 3. The substrate processing apparatus according to claim 1, wherein the brush portion of the scrub cleaning member is disposed so as to cover a region from a center portion to a peripheral portion of the substrate. A pair of the scrubbing member, the pair of scrub cleaning member is disposed opposite so as to sandwich the substrate held by the substrate holding means from above and below, intended to scrub clean the upper and lower surfaces of the substrate the substrate processing apparatus according to any one of 3 claims 1, characterized in that. Brush portion of the scrubbing member is a substrate processing apparatus according to any one of claims 1 to 4, characterized in that it is arranged in a cross shape to the base portion.

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