JP5115144B2 - Electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure suitable for achieving effective use of a mounting space on one-side surface of a board and simplification of an arrangement process of a reinforcing resin when a dam part for preventing projection of the reinforcing resin, in an electronic device composed by mounting a plurality of electronic components on one-side surface of a board and by applying reinforcement by a reinforcing resin to a part of the plurality of electronic components. <P>SOLUTION: On the one-side surface 11 of the board 10, a first electronic component arrangement region D1 being a continuing single region is formed where a plurality of first electronic components 20 and 22 with connection parts to the board 10 reinforced by the reinforcing resin 50 are arranged, and second electronic components 21 of which the connection parts to the board 10 are not reinforced by the reinforcing resin 50 are not arranged; and the dam part 60 for preventing the reinforcing resin 50 from projecting to the outside of the first electronic component arrangement region D1 on the one-side surface 11 of the board 10 is formed in the outer periphery of the first electronic component arrangement region D1. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an electronic device in which a plurality of electronic components are mounted on one surface of a substrate, and some electronic components are reinforced by underfill.

  2. Description of the Related Art Conventionally, an electronic device in which a plurality of electronic components are mounted on one surface of a substrate and the substrate and the plurality of electronic components are connected is widely known. In such a case, the plurality of electronic components have a connection portion between the substrate and a portion where the connection portion with the substrate is reinforced by a reinforcing resin called an underfill (hereinafter referred to as a first electronic component). In general, it is composed of one that is not reinforced by a reinforcing resin (hereinafter referred to as a second electronic component).

  On the other hand, conventionally, in a configuration in which a semiconductor element is soldered on a substrate and a reinforcing resin is filled between the element and the substrate in order to improve the reliability of the connection portion, a dam is provided around the semiconductor element, There has been proposed one in which the protrusion of the reinforcing resin is stopped (see, for example, Patent Document 1).

Here, among electronic components, FC (flip chip) that mounts solder bumps on the substrate and CSP (chip size package) that has bumps on the entire surface are filled with reinforcing resin to improve reliability. However, for electronic components such as diodes and transistors, mini-molded products, surface mount type inductors, and aluminum electrolytic capacitors, similar reinforcement is possible depending on the large thermal expansion difference between the substrate and the component, and depending on the component electrode type. Reinforcement with resin for use may be necessary.
JP 2006-351559 A

  Here, based on the prior art, the present inventor has experimentally studied an electronic device in which a plurality of electronic components are mounted on one surface of a substrate and the substrate and the plurality of electronic components are connected. FIG. 8 is a diagram showing a schematic plan configuration of an electronic device as a prototype. In FIG. 8, the surface of the reinforcing resin 50 is point-hatched for convenience of identification.

  In the electronic device shown in FIG. 8, the plurality of electronic components 20, 21, and 22 mounted on the one surface 11 of the substrate 10 have a first portion in which a connection portion with the substrate 10 is reinforced by a reinforcing resin 50. The connection parts between the electronic components 20 and 22 and the substrate 10 are constituted by the second electronic component 21 that is not reinforced by the reinforcing resin 50.

  The first electronic component is a semiconductor element 20 such as FC or CSP, or a molded element 22 such as a molded diode, which is connected to the substrate 10 by solder (not shown) and reinforces the solder connection portion. The resin 50 is reinforced.

  On the other hand, as the second electronic component, a bare chip semiconductor element 21 is mounted, which is connected to the electrode 12 on the one surface 11 of the substrate 10 through a metal wire 40. In addition, here, on one surface 11 of the substrate 10, there are an inspection electrode 14 and an external connection electrode 13 connected to the outside by wire bonding or welding.

  As shown in this prototype, conventionally, from the viewpoint of design, in order to form a circuit, various electronic components and electrodes are usually randomly arranged on one surface of a substrate. In this case, the reinforcing resin 50 is disposed by being applied and cured on the one surface 11 of the substrate 10, but in the application step, the reinforcing resin 50 is changed due to the amount of the resin or the displacement of the arrangement position. There is a possibility that the electronic component 21 and the electrodes 12 to 14 and the like that are not provided with the reinforcing resin 50 may adhere to cause problems.

  Here, in view of the above-mentioned Patent Document 1, there is also a plan to provide a dam so as to surround each component for each of the first electronic components that require the reinforcing resin, but the mounting area increases accordingly, In addition, the number of man-hours for the coating process increases, which is not desirable.

  The present invention has been made in view of the above problems, and in an electronic device in which some electronic components among a plurality of electronic components mounted on one surface of a substrate are reinforced with a reinforcing resin. The purpose is to provide a configuration suitable for realizing effective use of the mounting space on one side of the board and simplification of the placement process of the reinforcing resin when providing a dam for preventing the resin from sticking out. To do.

In order to achieve the above object, according to the present invention, a plurality of first electrons in which a connection portion with a substrate (10) is reinforced by a reinforcing resin (50) on one surface (11) of the substrate (10). The component (20, 22) is arranged, and the second electronic component (21) in which the connection portion with the substrate (10) is not reinforced by the reinforcing resin (50) is a single continuous region where the component (20, 22) is not arranged. A plurality of first electronic component placement areas (D1) are provided, and the first electrons on one surface (11) of the substrate (10) are arranged on the outer periphery of each first electronic component placement area (D1). A dam portion (60) that prevents the reinforcing resin (50) from protruding outside the component placement region (D1) is provided . In each of the plurality of first electronic component placement regions (D1), individual first 1 in the electronic component placement region (D1) The thickness of the uniform, than between different first electronic component placement area (D1), characterized in that the thickness of the reinforcement resin (50) are different from each other (see FIG. 4 described later).

  According to this, a plurality of first electronic components (20, 22) that need to be reinforced by the reinforcing resin (50) are arranged together, and the outside is surrounded by the dam portion (60), thereby reinforcing resin (50 ) Is prevented from protruding on the one surface (11) of the substrate (10) as compared with the case where the dam portion (60) is provided for each of the first electronic components (20, 22). The component mounting area can be reduced, and the reinforcing resin (50) can be collectively disposed with respect to the plurality of first electronic components (20, 21) in the dam portion (60).

  Therefore, in providing the dam portion (60), a configuration suitable for realizing effective use of the mounting space on the one surface (11) of the substrate (10) and simplification of the arrangement process of the reinforcing resin (50). Can be provided.

According to the first aspect of the present invention, when a plurality of first electronic component placement areas (D1) are provided, the thickness of the reinforcing resin (50) is within each first electronic component placement area (D1). Are uniform, and the thickness of the reinforcing resin (50) is different between the different first electronic component placement regions (D1). If it does in this way, since it can put together for every 1st electronic component (22) with the same thickness of the reinforcing resin (50), arrangement | positioning of the reinforcing resin (50) can be performed efficiently.

  Further, if the stress relaxation member (70) having a larger elastic modulus than the reinforcing resin (50) is arranged inside the reinforcing resin (50) inside the dam part (60), one continuous reinforcement is provided. Even if the arrangement area of the resin for resin (50) is increased, the stress relaxation member (70) can reduce the stress inside the resin and prevent the reinforcing resin (50) from cracking (described later). 6 and FIG. 7).

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
FIG. 1 is a schematic plan view showing the electronic device S1 according to the first embodiment of the present invention, and shows a planar configuration on the one surface 11 side of the substrate 10. As shown in FIG. In FIG. 1, the surface of the reinforcing resin 50 is point-hatched for convenience for identification. FIG. 2 is a schematic cross-sectional view of the electronic device S1 taken along the dashed line AA in FIG.

  A plurality of electronic components 20, 21, and 22 are mounted on one surface 11 of the substrate 10, and the substrate 10 and the electronic components 20 to 22 are electrically connected via the solder 30 and bonding wires 40.

  The substrate 10 can employ a ceramic substrate, a printed substrate, a lead frame, or the like, and is not particularly limited. On one surface 11 of the substrate 10, a wire electrode 12 connected to the bonding wire 40, an external connection electrode 13 for connecting to the outside, and an inspection electrode 14 used for inspection are provided. These electrodes 12-14 are comprised from the thick film and plating which used materials, such as Cu, Au, and Ag.

  In the electronic components 20 to 22, the first electronic components 20 and 22 in which the connection portion with the substrate 10 is reinforced by the reinforcing resin 50 and the connection portion between the substrate 10 and the first electronic components 20 and 22 are not reinforced by the reinforcing resin 50. 2 electronic components 21.

  Specifically, the first electronic components 20 and 22 include a first semiconductor element 20 such as FC or CSP, and a molded element 22 such as a molded diode or a molded transistor.

  As shown in FIG. 2, the first semiconductor element 20 is connected to the substrate 10 via a solder 30. Further, although not shown, the mold element 22 is connected to the substrate 10 via solder. As these solders 30, a solder material generally used for this type of electronic device is used. Specifically, eutectic solder or lead-free solder is used.

  In the first electronic components 20 and 22, the reinforcing resin 50 is filled between the first electronic components 20 and 22 and the one surface 11 of the substrate 10. Accordingly, the reinforcing resin 50 is disposed so as to seal the solder 30 between the component and the substrate, and the connection portion by the solder 30 is reinforced.

  Such a reinforcing resin 50 is generally used in the field of semiconductor devices and is made of, for example, an epoxy resin. Here, the reinforcing resin 50 may include a filler made of an inorganic material such as silica as in the normal case, or may not be included at all.

  Here, the second electronic component 21 is a second semiconductor element 21 made of a bare chip or the like, and the second semiconductor element 21 is placed on a surface 11 of the substrate 10 via a die mount material (not shown). Are fixed.

  The second semiconductor element 21 and the wire electrode 12 are connected by a bonding wire 40 and are electrically connected. The bonding wire 40 is made of general Au or Al.

  Here, in the electronic device S1 of the present embodiment, the first surface 11 of the substrate 10 is provided with a first electronic component placement region D1, which is a continuous region, and this first electronic component placement. In the region D1, a plurality of first electronic components 20 and 22 are arranged in close proximity to each other.

  In the present embodiment, one first electronic component placement region D1 is provided, in which only all the first electronic components 20 and 22 in the electronic device S1 are placed. Further, the second electronic component 21 and the electrodes 12 to 14 are not arranged in the first electronic component arrangement region D1.

  The second electronic component 21 and each of the electrodes 12 to 14 are members that cause problems when the reinforcing resin 50 adheres, and are members that do not want the reinforcing resin 50 to adhere. The members 12 to 14 and 21 to which the reinforcing resin 50 including the second electronic component 21 is not desired are disposed in a portion other than the first electronic component disposition region D1 on the one surface 11 of the substrate 10. Yes.

  And the dam part 60 is provided in the outer periphery of the 1st electronic component arrangement | positioning area | region D1. Here, the dam portion 60 has an annular shape and is provided so as to surround the region D1. The substantially entire upper surface of the reinforcing resin 50 is lower than the top of the dam portion 60, and the reinforcing resin 50 is accommodated in the inner periphery of the dam portion 60.

  In this manner, the dam portion 60 divides the first electronic component placement region D1 and the members 12 to 14 and 21 to which the reinforcing resin 50 located outside thereof is not to be attached. The dam portion 60 prevents the reinforcing resin 50 from protruding outside the first electronic component placement region D1 on the one surface 11 of the substrate 10.

  The dam portion 60 is produced by firing a thick film conductor or glass when the substrate 10 is produced, or is produced with a resin such as silicone resin, epoxy resin, polyimide, or solder when mounting a component, or a combination of both. It is formed by doing.

  In the electronic device S1, the electronic components 20 to 22 and the electrodes 12 to 14 are electrically connected by a wiring (not shown) formed on the surface or inside of the substrate 10, and The circuit is configured.

  An example of a method for manufacturing such an electronic device S1 will be described. In the substrate 10 on which the electrodes 12 to 14 are formed on the one surface 11, a dam portion 60 is formed on the one surface 11, and the first electronic components 20 and 22 are connected to the inner periphery of the dam portion 60 via the solder 30. Connecting.

  At this time, it is desirable to consider the distance and arrangement between the first electronic components 20 and 22 to be as uniform as possible. Further, a space for forming the dam part 60 is left in the peripheral part of the first electronic component placement region D1. On the other hand, the second electronic component 21 is mounted on one surface 11 of the substrate 10 and wire bonding is performed.

  Thereafter, the reinforcing resin 50 is applied to the first electronic component placement region D1 in the dam portion 60 to fill the gap between the first electronic components 20 and 22 and the substrate 10 with the reinforcing resin 50. And cure it. When the reinforcing resin 50 is applied, since the dam portion 60 is present, the reinforcing resin 50 is prevented from protruding outside the first electronic component placement region D1. Thus, the electronic device S1 of the present embodiment is completed.

  By the way, according to the present embodiment, the plurality of first electronic components 20 and 22 are arranged on the one surface 11 of the substrate 10 and the second electronic component as a member for which the reinforcing resin 50 is not desired to be attached. 21 and the respective electrodes 12 to 14 are provided with a first electronic component placement region D1 which is one continuous region where no placement is provided, and on the outer periphery of the region D1 on the outer surface of the region D1 on the one surface 11 of the substrate 10. A dam portion 60 is provided to prevent the reinforcing resin 50 from protruding.

  According to this, since the plurality of first electronic components 20 and 22 that need to be reinforced with the reinforcing resin 50 are arranged together and the outside is surrounded by the dam portion 60, the protruding of the reinforcing resin 50 can be prevented. Compared with the case where the dam portion 60 is provided for each of the first electronic components 20 and 22, the component mounting area on the one surface 11 of the substrate 10 can be reduced.

  In addition, since the reinforcing resin 50 can be collectively disposed with respect to the plurality of first electronic components 20 and 21 in the dam portion 60, each of the first electronic components 20 and 22 is one by one. Compared with the case where the reinforcing resin 50 is provided for the individual, the resin can be arranged efficiently.

  As described above, according to the present embodiment, when the dam portion 60 is provided for the purpose of preventing the protrusion of the reinforcing resin 50, the mounting space on the first surface 11 of the substrate 10 is effectively used and the arrangement process of the reinforcing resin 50 is simplified. It is possible to provide a configuration suitable for realizing the above.

(Second Embodiment)
FIG. 3 is a schematic plan view showing the main part of the method for manufacturing an electronic device according to the second embodiment of the present invention, and shows the state of the multiple substrate.

  In some cases, the substrate 10 is configured as a substrate obtained by dividing a multiple substrate and the first electronic component placement region D1 is formed at the corner of the one surface 11 of the substrate 10. In this case, the mounting of the electronic components 20 to 22, the formation of the dam portion 60, and the placement of the reinforcing resin 50 are performed on the substrate 10 in the multiple state, and then the multiple substrate 10 is moved along the dividing line L. May be divided. Thereby, man-hours can be reduced.

  In this case, since the first electronic component placement region D1 is located at the corner of the one surface 11 of the substrate 10, it is not surrounded by the dam portion 60 as in the first embodiment. The dam portion 60 does not exist at the end of the substrate 10. However, this does not affect the protrusion of the reinforcing resin 50.

(Third embodiment)
4A and 4B are diagrams showing the main part of the electronic device S2 according to the third embodiment of the present invention, in which FIG. 4A is a schematic plan view of one surface 11 side of the substrate 10, and FIG. It is a schematic sectional drawing in alignment with BB dashed-dotted line. In FIG. 4, the second electronic component, the electrode, and the like are omitted.

  As shown in FIG. 4, in the electronic device S2 of the present embodiment, two first electronic component placement areas D1 are provided on one surface 11 of the substrate 10, and each first electronic component placement area D1 is provided. A dam part 60 is provided.

  Here, in the first electronic component placement region D1 on the left side in FIG. 4, a plurality of relatively large mold elements 22 are arranged in a group, and in the first electronic component placement region D1 on the right side, A plurality of relatively small mold elements 22 are arranged and arranged. In both of the areas D1, the reinforcing resin 50 is accommodated on the inner periphery of the dam portion 60, so that the area D1 is prevented from protruding to the outside.

  Here, the large mold element 22 on the left side and the small mold element 22 on the right side in FIG. 4 have different gaps between the component and the substrate, and the large one is larger. Therefore, in the two first electronic component arrangement regions D1, the thickness of the reinforcing resin 50 is also different from each other, and the reinforcing resin 50 is thicker in the large left side.

  That is, here, in the two first electronic component placement regions D1, the thickness of the reinforcing resin 50 is uniform in one first electronic component placement region D1, and the first electronic components are mutually connected. The thickness of the reinforcing resin 50 is different between the arrangement regions D1.

  Therefore, in the present embodiment, when there are first electronic components having different thicknesses of the necessary reinforcing resin 50, the first electronic components 22 having the same thickness of the reinforcing resin 50 are grouped together. Therefore, the reinforcing resin 50 can be arranged efficiently.

  In the above example, the case where the thickness of two different types of reinforcing resin 50 exists is shown. However, when the thickness of three or more types of different reinforcing resin 50 exists, the first electronic component You may provide three or more arrangement | positioning area | region D1 according to the said kind instead of two. Also in this case, in the plurality of first electronic component arrangement regions D1 of three or more, the thickness of the reinforcing resin 50 is uniform in each region D1, and the reinforcing resin 50 is different between the different regions D1. The thickness may be different from each other.

  Furthermore, even if the thicknesses of the reinforcing resins 50 of the first electronic components are all the same, a plurality of first electronic component arrangement regions D1 may be provided. In this case, it is also possible to distinguish and arrange each region D1 according to the type and shape of the first electronic component.

(Fourth embodiment)
FIG. 5 is a schematic cross-sectional view showing a main part of an electronic device according to the fourth embodiment of the present invention. Here, only the dam portion 60 of the present embodiment provided on the one surface 11 of the substrate 10 is shown, and other members are omitted.

  In the present embodiment, a plurality of first electronic component placement areas D1 are provided as in the third embodiment, but the height of the dam portion 60 is different between different first electronic component placement areas D1. Are different.

  In this case, the formation method of the dam part 60 from which height differs is as follows. First, when the substrate 10 is fired, a dam portion 60 having a constant thickness is formed as a thick film conductor. This completes the lower dam 60 on the left side of FIG. Next, with respect to the high dam portion 60 on the right side of FIG. 5, an additional portion 60a is further formed on the dam portion 60 with the constant thickness by solder, and the high dam portion 60 including the additional portion 60a To do.

  Here, as the thick film conductor, a conductor paste such as Cu or Ag is used, and the dam portion 60 is formed by applying and curing the paste. In forming the high dam portion 60, in the above example, different materials are used in the upper and lower sides, such as the thick film conductor on the lower side and the solder on the upper addition portion 60a. The part 60a may be made of the same material such as a silicone resin.

  In this case, for example, when the silicone resin is disposed by dispensing, it is possible to change the height of the dam portion 60 by changing the needle diameter or by applying twice or three times.

  Different heights of the dam portions 60 between different first electronic component placement areas D1 as in the present embodiment are different between different first electronic component placement areas D1 as in the third embodiment. This is effective when the reinforcing resins 50 have different thicknesses. That is, the dam portion 60 may be raised in the region D1 where the reinforcing resin 50 is thick, and the dam portion 60 may be lowered in the region D1 where the reinforcing resin 50 is thin.

(Fifth embodiment)
6A and 6B are diagrams showing the main part of an electronic device S3 according to a fifth embodiment of the present invention, where FIG. 6A is a schematic plan view of one side 11 of the substrate 10, and FIG. 6B is stress relaxation described later. It is a partial schematic sectional drawing of the member 70 and its vicinity part.

  When the area of the reinforcing resin 50 in the dam portion 60, that is, the first electronic component placement region D1 is increased, there is a concern that stress increases and cracks are generated in the reinforcing resin 50. Therefore, in the present embodiment, the stress relaxation member 70 having a larger elastic modulus than the reinforcing resin 50 is disposed inside the reinforcing resin 50 inside the dam portion 60.

  Here, the stress relaxation member 70 has a rod shape, and is provided on the one surface 11 of the substrate 10 so as to protrude in the same manner as the dam portion 60. Further, the stress relaxation member 70 is provided in a position that does not overlap the first electronic components 20 and 22 in the first electronic component placement region D1, that is, a position different from the first electronic components 20 and 22. is required.

  In the case where the reinforcing resin 50 is an epoxy resin, examples of the material of the stress relaxation member 70 include a silicone resin. However, even if the same epoxy resin is used, the amount of the filler can be changed from the reinforcing resin 50. As long as the elastic modulus is large.

  The stress relaxation member 70 is formed by applying and curing the silicone resin or the like on the one surface 11 of the substrate 10. The formation timing may be performed, for example, when the dam portion 60 is formed, or after the dam portion 60 is formed and the electronic components 20 to 22 are mounted. In short, it may be before application of the reinforcing resin 50.

  According to this embodiment, even if the arrangement area of one continuous reinforcing resin 50 is increased by widening the first electronic component arrangement region D1, the stress relaxation member 70 causes the stress inside the resin to increase. Therefore, generation of cracks in the reinforcing resin 50 can be prevented.

  FIG. 7 is a diagram showing a schematic plan configuration of a main part of an electronic device as another example of the fifth embodiment, and is a schematic plan view on the one surface 11 side of the substrate 10. In the example shown in FIG. 6, the stress relaxation member 70 has a rod shape, but the shape of the stress relaxation member 70 may be spherical as shown in FIG. 7. In this case, there is an advantage that it can be easily arranged where necessary in comparison with the rod-shaped one. In addition to these shapes, the shape of the stress relaxation member 70 can be changed as appropriate.

(Other embodiments)
In addition, you may combine each above-mentioned embodiment suitably in the possible range. For example, a plurality of first electronic component placement regions D1 may be provided on the one surface 11 of the substrate 10, and the stress relaxation member 70 may be disposed inside the reinforcing resin 50 for each region D1.

1 is a schematic plan view showing an electronic device according to a first embodiment of the present invention. It is a schematic sectional drawing in alignment with the AA dashed-dotted line in FIG. It is a schematic plan view which shows the principal part of the manufacturing method of the electronic device which concerns on 2nd Embodiment of this invention. It is a figure which shows the electronic device which concerns on 3rd Embodiment of this invention, (a) is a schematic plan view, (b) is a schematic sectional drawing along the BB dashed-dotted line in (a). It is a schematic sectional drawing which shows the principal part of the electronic device which concerns on 4th Embodiment of this invention. It is a figure which shows the principal part of the electronic device which concerns on 5th Embodiment of this invention, (a) is a schematic plan view, (b) is a partial schematic sectional drawing of the vicinity part of a stress relaxation member. It is a schematic plan view of the principal part of the electronic apparatus as another example of the said 5th Embodiment. It is a schematic plan view of the electronic device as a prototype of the present inventor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Board | substrate, 11 ... One surface of a board | substrate, 20 ... 1st semiconductor element as 1st electronic component,
21 ... Second semiconductor element as second electronic component,
22 ... Mold element as first electronic component, 50 ... Reinforcing resin, 60 ... Dam part,
70: Stress relaxation member, D1: First electronic component placement region.

Claims (2)

A plurality of electronic components (20, 21, 22) are mounted on one surface (11) of the substrate (10), and the substrate (10) and the plurality of electronic components (20-22) are connected,
The plurality of electronic components are connected to the substrate (10) and the first electronic component (20, 22) in which the connection to the substrate (10) is reinforced by a reinforcing resin (50). In the electronic device constituted by the second electronic component (21) which is not reinforced by the reinforcing resin (50),
On one surface (11) of the substrate (10), a plurality of the first electronic components (20, 22) are arranged and one continuous region where the second electronic components (21) are not arranged. A plurality of first electronic component placement regions (D1) are provided,
On the outer periphery of each of the first electronic component placement regions (D1), the reinforcing resin (50) is disposed outside the first electronic component placement region (D1) on one surface (11) of the substrate (10). A dam (60) is provided to prevent overhanging ,
In the plurality of first electronic component arrangement regions (D1), the thickness of the reinforcing resin (50) is uniform in each of the first electronic component arrangement regions (D1), and the first electronic component arrangement regions (D1) are different. The electronic device is characterized in that the reinforcing resin (50) has a different thickness between the electronic component placement regions (D1) . A stress relaxation member (70) having a higher elastic modulus than the reinforcing resin (50) is disposed inside the reinforcing resin (50) inside the dam portion (60). The electronic device according to claim 1 .

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