JP2005072201A - Stencil mask, manufacturing method therefor, and method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stencil mask where a micropattern that is beyond the working limit of a mask can be formed, to provide its manufacturing method, and to provide a method of manufacturing a semiconductor device. <P>SOLUTION: The method of manufacturing the stencil mask 5 comprises processes of forming a first opening pattern 1a that hardly penetrates through the mask board 1 but is cut half or above as deep as the thickness of a mask board 1 on the one surface of a mask board 1, and of forming a second opening pattern 1b that overlaps partially with the first opening pattern 1a and is cut half or above as deep as the thickness of a mask board 1 on the other surface of the mask board 1. In the process of forming the second opening pattern 1b, a micro through-pattern 1c is formed through a part of the mask board, where the first opening pattern 1a and the second opening pattern 1b overlap with each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stencil mask, a manufacturing method thereof, and a manufacturing method of a semiconductor device. In particular, the present invention relates to a stencil mask capable of forming a fine pattern exceeding the processing limit of the mask, a manufacturing method thereof, and a manufacturing method of a semiconductor device. The present invention also relates to a stencil mask that can form a fine pattern on a mask relatively easily, a method for manufacturing the same, and a method for manufacturing a semiconductor device.

  In recent years, with the high integration of semiconductor integrated circuits, charged particle beams such as electron beams, ion beams, or X-rays are used instead of photolithography technology using light, which has been the mainstream means for forming fine patterns for many years. New exposure methods have been studied and put into practical use. Among them, the electron beam exposure that forms a pattern using an electron beam has a great feature in that a fine pattern of 0.1 μm or less can be produced because the electron beam itself can be narrowed down to several nm. ing.

10A to 10C are cross-sectional views illustrating a conventional method for manufacturing a stencil mask for electron beam exposure.
First, as shown in FIG. 10A, a mask substrate 101 made of silicon or the like is prepared, and a resist film is applied on the mask substrate 101. Next, the resist film is exposed and developed using an electron beam drawing apparatus or the like, whereby a resist pattern 102 is formed on the mask substrate 101. The opening portion of the resist pattern 102 shown in FIG. 10A is a portion of the resolution limit width 103 of the electron beam drawing apparatus. The resolution limit width corresponds to the minimum line width that can be formed with a pattern.

Next, as shown in FIG. 10B, by etching the mask substrate 101 using the resist pattern 102 as a mask, a pattern 101 a corresponding to the resist pattern 102 is opened in the mask substrate 101.
Thereafter, as shown in FIG. 10C, the resist pattern 102 is removed. In this way, the stencil mask 104 in which the opening pattern is formed on the mask substrate 101 is manufactured.

There is a method using an electron beam and a transfer mask in a pattern formation method in semiconductor manufacturing. However, when a stencil mask is used, there is an advantage that the structure of the hard surface can be simplified, but it is necessary to make the mask at the same magnification. There is a problem that the processing limit of the mask cannot be exceeded for miniaturization.
That is, in the above-described conventional stencil mask manufacturing method, the resolution limit width 103 when the resist film is exposed to the pattern becomes the processing limit width 103 of the pattern formed on the stencil mask 104, which leads to processing accuracy. Therefore, when a fine pattern is formed on a semiconductor substrate using the stencil mask, a fine pattern exceeding the processing limit as described above cannot be formed on the semiconductor substrate.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a stencil mask capable of forming a fine pattern exceeding the processing limit of the mask, a manufacturing method thereof, and a manufacturing method of a semiconductor device. It is in. Another object of the present invention is to provide a stencil mask capable of forming a fine pattern on the mask relatively easily, a method for manufacturing the same, and a method for manufacturing a semiconductor device.

In order to solve the above-described problem, a method for manufacturing a stencil mask according to the present invention includes a first hole pattern that has a depth that is more than half of the thickness of the mask substrate on one main surface of the mask substrate but does not allow penetration. Forming a step;
Forming, on the other main surface of the mask substrate, a second hole pattern having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first hole pattern;
A method for producing a stencil mask comprising:
In the step of forming the second hole pattern, a fine through pattern is formed by penetrating the portion of the mask substrate where the first hole pattern and the second hole pattern overlap.

  According to the stencil mask manufacturing method, since the fine through pattern is formed by penetrating the portion of the mask substrate where the first hole pattern and the second hole pattern overlap, the processing accuracy is improved and the fine pattern is formed. A stencil mask formed with a pattern can be manufactured. Thereby, a mask corresponding to a finer design rule can be produced. Further, a fine pattern can be formed on the mask relatively easily.

  In the stencil mask manufacturing method according to the present invention, at least one of the first and second aperture patterns may be a pattern having a processing limit width of the mask substrate. Thereby, the stencil mask which formed the fine pattern exceeding a process limit can be manufactured.

In the method for manufacturing a stencil mask according to the present invention, at least one of the first and second aperture patterns may be a line pattern or a pattern having a part of the line pattern.
In the method for manufacturing a stencil mask according to the present invention, at least one of the first and second aperture patterns may be an L-shaped pattern or a pattern having an L-shaped pattern in part.

A stencil mask according to the present invention is formed on one main surface of a mask substrate, and has a first hole pattern that has a depth of half or more of the thickness of the mask substrate but does not penetrate therethrough,
A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern;
A through pattern formed on the mask substrate and formed in a portion where the first hole pattern and the second hole pattern overlap;
It comprises.

According to the stencil mask, a mask corresponding to a finer design rule can be obtained. It is also possible to use a stencil mask with a fine pattern.
In the stencil mask according to the present invention, the through pattern may be a pattern having a width narrower than a processing limit width of the mask substrate.

A stencil mask according to the present invention is a first hole pattern formed on one main surface of a mask substrate, having a depth of half or more of the thickness of the mask substrate, but not penetrating, wherein a line pattern is formed. A first aperture pattern in at least a portion;
A second hole pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first hole pattern. A second aperture pattern having at least a portion of the pattern;
A penetrating pattern formed on the mask substrate and formed in a portion where the first hole pattern and the second hole pattern overlap, and having a line pattern at least in part,
It comprises.

A stencil mask according to the present invention is a first opening pattern formed on one main surface of a mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating, and having an L-shaped pattern. A first aperture pattern having at least a portion thereof,
A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern;
A through pattern formed on the mask substrate and formed in a portion where the first aperture pattern and the second aperture pattern overlap, and having an L-shaped pattern at least in part,
It comprises.

A method for manufacturing a semiconductor device according to the present invention includes: a first hole pattern formed on one main surface of a mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating; A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern; A stencil mask having a through pattern formed in a portion where the first aperture pattern and the second aperture pattern overlap with each other, and
Exposing the resist film with an electron beam using the stencil mask as a mask and developing the resist film to form the through pattern in the resist film; and
It comprises.

  According to the method for manufacturing a semiconductor device, it is possible to form a fine through pattern in a resist film by using a stencil mask in which a fine through pattern is formed.

A method for manufacturing a semiconductor device according to the present invention includes: a first hole pattern formed on one main surface of a mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating; A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern; A stencil mask having a through pattern formed in a portion where the first aperture pattern and the second aperture pattern overlap with each other, and
Forming a work film on a semiconductor substrate and applying a resist film on the work film;
Exposing the resist film with an electron beam using the stencil mask as a mask and developing the resist film to form a resist pattern having the penetrating pattern transferred onto the film to be processed;
Forming the penetration pattern in the processed film by etching the processed film using the resist pattern as a mask;
It comprises.

  According to the method for manufacturing a semiconductor device, it is possible to form a fine through pattern in a film to be processed on a semiconductor substrate by using a stencil mask in which a fine through pattern is formed.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
1 and 2 are a plan view and a cross-sectional view showing a method for manufacturing a stencil mask according to Embodiment 1 of the present invention.
1A is a plan view showing one of manufacturing steps of a stencil mask according to Embodiment 1, and FIG. 1B is a cross-sectional view taken along line 1B-1B shown in FIG. FIG. 1C is a cross-sectional view showing the next step of FIG. 2A is a plan view showing the next step of FIG. 1C, and FIG. 2B is a cross-sectional view taken along line 2B-2B shown in FIG. 2 (C) is a cross-sectional view showing the next step of FIG. 2 (B), and FIG. 2 (D) is a cross-sectional view showing the next step of FIG. 2 (C).

  First, as shown in FIGS. 1A and 1B, a mask substrate 1 such as silicon is prepared. The mask substrate 1 is, for example, a silicon wafer thinned to a thickness of several hundred μm. Next, a resist film is applied on the surface of the mask substrate 1, and the resist film is exposed and developed using an electron beam drawing apparatus or the like, whereby a resist pattern 2 is formed on the mask substrate 1. . The opening pattern of the resist pattern 2 is an opened line pattern 2a having a resolution limit width 3 of the electron beam drawing apparatus as shown in FIG. The resolution limit width corresponds to the minimum line width that can be formed with a pattern.

Next, as shown in FIG. 1C, the mask substrate 1 is etched using the resist pattern 2 as a mask. At this time, etching is performed to a depth of half or more of the thickness of the mask substrate 1, but the penetration is not performed. As a result, a pattern 1 a corresponding to the line pattern 2 a of the resist pattern 2 is opened in the mask substrate 1.
Next, after removing the resist pattern 2, the mask substrate 1 is inverted.

  Thereafter, as shown in FIGS. 2A and 2B, a resist film is applied on the back surface of the mask substrate 1. Next, the resist film is exposed and developed using an electron beam drawing apparatus or the like, whereby a resist pattern 4 is formed on the back surface of the mask substrate 1. The opening pattern of the resist pattern 4 is a line pattern 4a having a hole having a resolution limit width 3 of the electron beam drawing apparatus as shown in FIG. The line pattern 4a is arranged so as to partially overlap the line pattern 1a.

  Next, as shown in FIG. 2C, the mask substrate 1 is etched using the resist pattern 4 as a mask. At this time, etching is performed to a depth of half or more of the thickness of the mask substrate 1, but no penetration is made. As a result, a pattern 1b corresponding to the line pattern 4a of the resist pattern 4 is opened in the mask substrate 1, and a through pattern 1c is formed at a portion where the pattern 1b and the pattern 1a overlap.

  Thereafter, as shown in FIG. 2D, the resist pattern 4 is removed. In this way, the stencil mask 5 in which the through pattern 1c is formed on the mask substrate 1 is manufactured. In this way, only the overlapped portion of the fine pattern of the processing limit overlapped on the upper and lower sides of the mask substrate is penetrated. Therefore, the penetration pattern 1c is a pattern having a width narrower than the resolution limit width (processing limit width) 3, and a stencil mask 5 on which a fine pattern exceeding the processing limit is formed can be obtained.

  According to the first embodiment, it is possible to manufacture a stencil mask in which a fine pattern exceeding the processing limit is formed. Thus, by improving the processing accuracy of the stencil mask, a mask corresponding to a finer design rule can be produced. Moreover, if the manufacturing method of this Embodiment is used, a highly accurate patterning (etching process) will become unnecessary and a fine pattern can be formed on a mask comparatively easily. In addition, a stencil mask can be manufactured at a low cost.

(Embodiment 2)
3 to 5 are sectional views and plan views showing a method for manufacturing a semiconductor device according to the second embodiment of the present invention.
4A is a plan view showing the next step of FIG. 3, and FIG. 4B is a cross-sectional view taken along line 4B-4B shown in FIG. 4A. 5A is a cross-sectional view showing the next step of FIG. 4, and FIG. 5B is a cross-sectional view showing the next step of FIG. 5A.

  First, as shown in FIG. 3, a film 7 to be processed is formed on the silicon substrate 6. The film 7 to be processed is a film to be etched, and may be a conductive film, an insulating film, or a semiconductor film. Next, a resist film 8 is applied on the film 7 to be processed. Next, the stencil mask 5 shown in FIG. 2D manufactured in the first embodiment is prepared, and the resist film 8 is exposed with an electron beam using the stencil mask 5 as a mask. Thereby, the region 8 a is exposed in the resist film 8.

  Thereafter, as shown in FIGS. 4A and 4B, the resist film 8 is developed, whereby a resist pattern 8b is formed on the film 7 to be processed. The resist pattern 8b has a line pattern 8c in which the region 8a is opened. This line pattern 8c corresponds to the penetration pattern 1c of the stencil mask 5 shown in FIG. 3, and is a fine pattern exceeding the processing limit.

Next, as shown in FIG. 5A, the processed film 7 is etched using the resist pattern 8b as a mask, whereby the line pattern 8c is transferred to the processed film 7.
Next, as shown in FIG. 5B, the resist pattern 8b is removed. In this way, a fine pattern can be formed on the film 7 to be processed. That is, by using the stencil mask 5 on which the fine pattern of the first embodiment is formed, it is possible to form a fine pattern on the film 7 to be processed on the silicon substrate 6.

(Embodiment 3)
6 and 7 are a plan view and a sectional view showing a method for manufacturing a stencil mask according to the third embodiment of the present invention.
FIG. 6A is a plan view showing one of manufacturing steps of the stencil mask according to the third embodiment, and FIG. 6B is a cross-sectional view taken along line 6B-6B shown in FIG. FIG. 6C is a cross-sectional view showing the next step of FIG. FIG. 7A is a plan view showing the next step of FIG. 6C, and FIG. 7B is a cross-sectional view taken along line 7B-7B shown in FIG. 7C is a cross-sectional view showing the next step of FIG. 7B, and FIG. 7D is a cross-sectional view showing the next step of FIG. 7C.

  First, as shown in FIGS. 6A and 6B, a mask substrate 11 made of silicon or the like is prepared. This mask substrate 11 is, for example, a silicon wafer thinned to a thickness of several hundred μm, as in the first embodiment. Next, a resist film is applied on the surface of the mask substrate 11, the resist film is exposed and developed using an electron beam drawing apparatus or the like, and a resist pattern 12 is formed on the mask substrate 11. . The opening pattern of the resist pattern 12 is an opened L-shaped pattern (in other words, a key-shaped pattern) 12a having a resolution limit width 3 of the electron beam drawing apparatus as shown in FIG.

Next, as shown in FIG. 6C, the mask substrate 11 is etched using the resist pattern 12 as a mask. At this time, etching is performed to a depth of half or more of the thickness of the mask substrate 11, but the penetration is not performed. As a result, a pattern 11 a corresponding to the L-shaped pattern 12 a of the resist pattern 12 is opened in the mask substrate 11.
Next, after removing the resist pattern 12, the mask substrate 11 is inverted.

  Thereafter, as shown in FIGS. 7A and 7B, a resist film is applied on the back surface of the mask substrate 11. Next, the resist film is exposed and developed using an electron beam drawing apparatus or the like, whereby a resist pattern 14 is formed on the back surface of the mask substrate 11. The opening pattern of the resist pattern 14 is a rectangular pattern 14a having openings as shown in FIG. This square pattern 14a is arranged so as to partially overlap the L-shaped pattern 11a.

  Next, as shown in FIG. 7C, the mask substrate 11 is etched using the resist pattern 14 as a mask. At this time, etching is performed to a depth of half or more of the thickness of the mask substrate 11, but the penetration is not performed. As a result, a pattern 11b corresponding to the square pattern 14a of the resist pattern 14 is opened in the mask substrate 11, and a through pattern 11c is formed in a portion where the pattern 11b and the pattern 11a overlap.

  Thereafter, as shown in FIG. 7D, the resist pattern 14 is removed. In this way, the stencil mask 15 in which the through pattern 11c is formed on the mask substrate 11 is manufactured. In this way, only the overlapping portion of the fine pattern (L-shaped pattern) and the rectangular pattern on the upper and lower sides of the mask substrate is penetrated. Therefore, the penetration pattern 11c is a pattern having a width narrower than the resolution limit width (processing limit width) 3, and a stencil mask 15 on which a fine pattern exceeding the processing limit is formed can be obtained.

In the third embodiment, the same effect as in the first embodiment can be obtained.
In the present embodiment, a stencil mask in which an L-shaped through pattern different from that in the first embodiment is formed can be obtained.

(Modification 1)
FIG. 8 is a plan view showing Modification 1 in which the line pattern of Embodiment 1 and the L-shaped pattern of Embodiment 3 are combined.
A pattern 21a in which an L-shaped pattern and a line pattern are combined is formed on one main surface of the mask substrate 21 so as to have a depth of half or more of the thickness of the mask substrate 21 but not to penetrate. On the other main surface of the mask substrate 21, a pattern 21 b obtained by combining a square pattern and a line pattern is formed so as not to penetrate through the mask substrate 21 with a depth more than half of the thickness of the mask substrate 21. Then, only the portion where the pattern 21a and the pattern 21b overlap is penetrated to form the penetrating pattern 21c.

  The modification 1 is an example in which the line pattern of the first embodiment and the L-shaped pattern of the third embodiment are combined, but various patterns are formed by combining the line pattern and the L-shaped pattern by various methods. It becomes possible.

(Modification 2)
FIG. 9 is a plan view showing Modification 2 in which the L-shaped patterns of Embodiment 3 are combined.
A pattern 31a in which two L-shaped patterns are combined is formed on one main surface of the mask substrate 31 so as to have a depth of half or more of the thickness of the mask substrate 31 but not to penetrate. A rectangular pattern 3b is formed on the other main surface of the mask substrate 31 so as to have a depth more than half of the thickness of the mask substrate 31 but not to penetrate. Then, only the portion where the pattern 31a and the pattern 31b overlap is penetrated to form the penetrating pattern 31c.

Although the said modification 2 is an example which combined the L-shaped pattern of Embodiment 3, it becomes possible to form various patterns by combining a line pattern and an L-shaped pattern by various methods.
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, it is possible to use a combination of a line pattern and an L-shaped pattern different from those of the first and second modifications.

FIG. 6 is a plan view and a cross-sectional view showing the method for manufacturing the stencil mask according to the first embodiment. FIG. 6 is a plan view and a cross-sectional view showing the method for manufacturing the stencil mask according to the first embodiment. Sectional drawing which shows the manufacturing method of the semiconductor device by Embodiment 2. FIG. Sectional drawing which shows the manufacturing method of the semiconductor device by Embodiment 2. FIG. Sectional drawing which shows the manufacturing method of the semiconductor device by Embodiment 2. FIG. FIG. 6 is a plan view and a cross-sectional view showing a method for manufacturing a stencil mask according to a third embodiment. FIG. 6 is a plan view and a cross-sectional view showing a method for manufacturing a stencil mask according to a third embodiment. The top view which shows the modification 1 of embodiment. The top view which shows the modification 2 of embodiment. Sectional drawing which shows the manufacturing method of the stencil mask for the conventional electron beam exposure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mask substrate, 1a, 1b ... Pattern, 1c ... Through pattern, 2 ... Resist pattern, 2a ... Line pattern, 3 ... Resolution limit width (processing limit width), 4 ... Resist pattern, 4a ... Line pattern, 5 ... Stencil mask, 6 ... silicon substrate, 7 ... film to be processed, 8 ... resist film, 8a ... exposure region, 8b ... resist pattern, 8c ... line pattern, 11 ... mask substrate, 11a, 11b ... pattern, 11c ... penetrating pattern, DESCRIPTION OF SYMBOLS 12 ... Resist pattern, 12a ... Line pattern, 14 ... Resist pattern, 14a ... Line pattern, 15 ... Stencil mask, 21, 31 ... Mask substrate, 21a, 21b, 31a, 31b ... Pattern, 21c, 31c ... Through pattern, 101 ... Mask substrate, 101a ... Pattern, 102 ... Resist pattern, 103 ... Solution Limits the width (processing limit width), 104 ... stencil mask

Claims (10)

Forming a first hole pattern on one main surface of the mask substrate that has a depth of half or more of the thickness of the mask substrate but does not penetrate;
Forming, on the other main surface of the mask substrate, a second hole pattern having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first hole pattern;
A method for producing a stencil mask comprising:
In the step of forming the second hole pattern, a stencil mask for forming a fine through pattern by penetrating the mask substrate in a portion where the first hole pattern and the second hole pattern overlap with each other is formed. Production method. The method for manufacturing a stencil mask according to claim 1, wherein at least one of the first and second aperture patterns is a pattern having a processing limit width of the mask substrate. The method for manufacturing a stencil mask according to claim 1 or 2, wherein at least one of the first and second aperture patterns is a line pattern or a pattern having a part of the line pattern. The method for manufacturing a stencil mask according to any one of claims 1 to 3, wherein at least one of the first and second aperture patterns is an L-shaped pattern or a pattern having an L-shaped pattern in part. A first aperture pattern formed on one main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating;
A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern;
A through pattern formed on the mask substrate and formed in a portion where the first hole pattern and the second hole pattern overlap;
A stencil mask comprising: The stencil mask according to claim 5, wherein the penetration pattern is a pattern having a width narrower than a processing limit width of the mask substrate. A first opening pattern which is formed on one main surface of the mask substrate and has a depth not less than half of the thickness of the mask substrate but does not penetrate, and has a line pattern at least in part. With an opening pattern,
A second hole pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first hole pattern. A second aperture pattern having at least a portion of the pattern;
A penetrating pattern formed on the mask substrate and formed in a portion where the first hole pattern and the second hole pattern overlap, and having a line pattern at least in part,
A stencil mask comprising: A first opening pattern which is formed on one main surface of the mask substrate and has a depth which is more than half of the thickness of the mask substrate but does not penetrate, and which has an L-shaped pattern at least in part. With an opening pattern of
A second aperture pattern formed on the other main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate and partially overlapping with the first aperture pattern;
A through pattern formed on the mask substrate and formed in a portion where the first aperture pattern and the second aperture pattern overlap, and having an L-shaped pattern at least in part,
A stencil mask comprising: Formed on one main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating, and formed on the other main surface of the mask substrate; A second hole pattern having a depth of half or more of the thickness of the mask substrate and partially overlapping the first hole pattern; and the first hole pattern formed on the mask substrate. And a stencil mask having a through pattern formed in a portion where the second aperture pattern overlaps, and
Exposing the resist film with an electron beam using the stencil mask as a mask and developing the resist film to form the through pattern in the resist film; and
A method for manufacturing a semiconductor device comprising: Formed on one main surface of the mask substrate, having a depth of half or more of the thickness of the mask substrate but not penetrating, and formed on the other main surface of the mask substrate; A second hole pattern having a depth of half or more of the thickness of the mask substrate and partially overlapping the first hole pattern; and the first hole pattern formed on the mask substrate. And a stencil mask having a through pattern formed in a portion where the second aperture pattern overlaps, and
Forming a work film on a semiconductor substrate and applying a resist film on the work film;
Exposing the resist film with an electron beam using the stencil mask as a mask and developing the resist film to form a resist pattern having the penetrating pattern transferred onto the film to be processed;
Forming the penetration pattern in the processed film by etching the processed film using the resist pattern as a mask;
A method for manufacturing a semiconductor device comprising:

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