JP2018039204A - Wound body and sheet for substrate, and wiring board and mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wound body capable of reducing falling off of inorganic insulating particles from an inorganic insulating layer and a sheet for substrate, and to provide a wiring board and a mounting structure.SOLUTION: A wound body has such a wound structure that a long laminated sheet 1 is wound in a length direction, where the laminated sheet 1 contains a long support sheet 5, an inorganic insulating layer 9 arranged on the support sheet 5 and a first resin layer 11 arranged on the inorganic resin layer 9, a side face of the inorganic insulating layer 9 in the width direction of the support sheet 5 is exposed, the inorganic resin layer 9 has a plurality of inorganic insulating particles 15 of which parts are connected to each other, the plurality of inorganic insulating particles 15 contain first inorganic insulating particles 15a having a particle size of 5-80 nm and second inorganic insulating particles 15b having a particle size of 0.1-5 μm, and at least N and C exist as elements on the surface of the first inorganic insulating particles 15a.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wound body, a board sheet, a wiring board, and a mounting structure.

  2. Description of the Related Art Conventionally, a mounting structure in an electronic device is known in which an electronic component is mounted on a wiring board. A laminated sheet for forming such a wiring board is configured by forming a resin layer on a copper foil (support sheet), for example. The laminated sheet is cut at the ears so that the widths of the support sheet and the resin layer are uniform, and wound to form a drum-shaped wound body, which is sold in this state. Alternatively, the laminated sheet is sold as a substrate sheet cut to a predetermined length.

  When producing a wiring board using a wound body, a laminated sheet is pulled out from the wound body by a predetermined length, cut into a predetermined length, and a plurality of the cut sheets for the substrate are in a vacuum state. Is heated and pressurized to be laminated. A part of the copper foil is etched to form a wiring.

  As a laminated sheet for producing such a wiring board, an inorganic insulating layer containing first inorganic insulating particles and second inorganic insulating particles having different particle sizes is formed on a support sheet, and the inorganic insulating layer is formed on the inorganic insulating layer. A resin layer is known (see Patent Document 1). This Patent Document 1 describes that the first inorganic insulating particles are bonded to each other, and the second inorganic insulating particles are bonded to each other through the first inorganic insulating particles to have a three-dimensional network structure skeleton. .

International Publication No. 2011/037260

  When the wound body or the substrate sheet is produced using the laminated sheet of Patent Document 1, the inorganic insulating particles may fall off from the side surface of the inorganic insulating layer. In addition, when forming a via hole in the inorganic insulating layer, the inorganic insulating particles may fall off from the via hole wall surface.

  An object of the present invention is to provide a wound body, a board sheet, a wiring board, and a mounting structure that can reduce the dropout of inorganic insulating particles from the inorganic insulating layer.

  The wound body of the present invention has a winding structure in which a long laminated sheet is wound in the length direction, and the laminated sheet includes a long supporting sheet and the supporting sheet. An inorganic insulating layer that is disposed, and a first resin layer disposed on the inorganic insulating layer, wherein the side surface of the inorganic insulating layer in the width direction of the support sheet is exposed, and the inorganic insulating layer is , Having a plurality of inorganic insulating particles connected to each other, the plurality of inorganic insulating particles being a first inorganic insulating particle having a particle size of 5 to 80 nm and a second inorganic particle having a particle size of 0.1 to 5 μm. Inorganic insulating particles are included, and at least N and C are present as elements on the surface of the first inorganic insulating particles.

The substrate sheet of the present invention has a rectangular shape having a pair of first sides and a pair of second sides opposed to each other on the main surface, a support sheet, an inorganic insulating layer disposed on the support sheet, and the inorganic sheet A first resin layer disposed on the insulating layer, wherein the side surface of the inorganic insulating layer in the width direction of the support sheet is exposed, and the inorganic insulating layer includes a plurality of mutually connected portions. The plurality of inorganic insulating particles include inorganic insulating particles, the first inorganic insulating particles having a particle size of 5 to 80 nm, and the second inorganic insulating particles having a particle size of 0.1 to 5 μm. At least N and C are present as elements on the surface of the inorganic insulating particles.

  The wiring board of the present invention is a wiring board comprising a first resin layer, an inorganic insulating layer disposed on the first resin layer, and a wiring disposed on the inorganic insulating layer, The inorganic insulating layer has a plurality of inorganic insulating particles connected to each other, and a first resin portion disposed between the plurality of inorganic insulating particles, and the plurality of inorganic insulating particles include grains. It includes first inorganic insulating particles having a diameter of 5 to 80 nm and second inorganic insulating particles having a particle diameter of 0.1 to 5 μm, and at least N and C are present as elements on the surface of the first inorganic insulating particles. It is characterized by.

  A mounting structure according to the present invention includes the above wiring board and an electronic component mounted on the wiring board and electrically connected to the wiring.

  In the present invention, dropping of inorganic insulating particles from the inorganic insulating layer can be reduced.

(A) is explanatory drawing which showed the outline of the wound body, (b) is sectional drawing which showed 1st Embodiment of the lamination sheet, (c) is a cross-sectional schematic diagram of an inorganic insulating layer. (A) is the top view which looked at the lamination sheet from the upper part, (b) is sectional drawing along the 2b-2b line of (a). (A) is sectional drawing which showed 2nd Embodiment of the lamination sheet, (b) is sectional drawing which showed 3rd Embodiment of the lamination sheet. The cut position of the ear | edge part of a lamination sheet is shown, (a) is a top view, (b) is sectional drawing along the 3b-3b line of (a). (A) is a top view which shows the cut position for obtaining the board | substrate sheet | seat from the lamination sheet of Fig.2 (a), (b) is the cross section (of the board | substrate sheet | seat) along the 4b-4b line of (a). FIG. 4C is a cross-sectional view (of the substrate sheet) taken along line 4c-4c in FIG. (A) is a cross-sectional schematic diagram which shows an inorganic insulating layer and its vicinity, (b) is explanatory drawing which shows the coupling | bonding state of an inorganic insulating particle. (A) is sectional drawing which shows a wiring board, (b) is sectional drawing which showed 1 process of the manufacturing method of a wiring board. (A) (b) is sectional drawing which showed 1 process of the manufacturing method of a wiring board.

  Hereinafter, the wound body will be described with reference to FIGS. Note that the wound body of the present disclosure is not limited to the following embodiment, and various changes and improvements can be made without departing from the gist of the present disclosure.

  Fig.1 (a) has shown the wound body from which the one part lamination sheet 1 was pulled out. The wound body is configured by winding a long laminated sheet 1 around a cylindrical core member 3 a plurality of times in the length direction. In addition, although Fig.1 (a) described what was wound once, it is comprised by winding in multiple times in fact.

  The long laminated sheet 1 has a long strip shape. The wound body is formed by winding the laminated sheet 1 around the core material 3 in a spiral shape, and is configured by winding the laminated sheet 1 around the core material 3 so as to surround the core material 3 multiple times. Yes.

This laminated sheet 1 is a support sheet 5 as shown in FIG. 1 (b) which is a cross section obtained by cutting the laminated sheet 1 of FIG. 1 (a) in the vertical direction (the thickness direction (Z-axis direction) of the laminated sheet 1). And an inorganic insulating layer 9 on the support sheet 5 and a first resin layer 11 on the inorganic insulating layer 9.

  As will be described later, the inorganic insulating layer 9 is configured by connecting or contacting a plurality of inorganic insulating particles 15 (hereinafter also referred to as connection), and there are voids between the inorganic insulating particles 15. . FIG. 2 shows a part of the laminated sheet 1, and the side surface in the width direction (Y-axis direction) of the support sheet 5 is composed of the side surfaces of the support sheet 5, the inorganic insulating layer 9, and the first resin layer 11. .

  As shown in FIG. 1C, the inorganic insulating layer 9 has a plurality of inorganic insulating particles 15 that are partially connected to each other, and the plurality of inorganic insulating particles 15 have a particle size of 5 to 80 nm. 1 inorganic insulating particles 15a and second inorganic insulating particles 15b having a particle size of 0.1 to 5 μm, and at least N and C are present as elements on the surface of the first inorganic insulating particles 15a. C may be present as an element on the surface of the second inorganic insulating particle 15b.

  The plurality of first inorganic insulating particles 15a are partially connected to each other, and the second inorganic insulating particles 15b are connected to each other via the connected first inorganic insulating particles 15a, or the second inorganic insulating particles 15a are connected. Some of the particles 15b are connected or in contact with each other.

  N and C as elements on the surface of the first inorganic insulating particle 15a can be present by subjecting the first inorganic insulating particle 15a to a surface treatment with a silane coupling agent containing N, as will be described later. As the silane coupling agent containing N, it is desirable to use a silane coupling agent having amine or amide as a functional group.

  Similarly, C on the surface of the second inorganic insulating particles 15b can be made to exist by surface-treating the second inorganic insulating particles 15b with a silane coupling agent. In particular, it is desirable to use a silane coupling agent having acrylic or methacryl as a functional group.

  Although elements other than N and C may exist as elements on the surface of the first inorganic insulating particles 15a, the amount is smaller than the total amount of N and C. Examples of elements other than N and C on the surface of the first inorganic insulating particle 15a include elements on the surface of the second inorganic insulating particle 15b.

  Although N may be present on the surface of the second inorganic insulating particle 15b, it is less than the amount of N on the surface of the first inorganic insulating particle 15a.

  As shown in FIG. 2B, the side surface in the Y-axis direction of the laminated sheet 1 is the same surface as the side surface 5a of the support sheet 5, the side surface 9a of the inorganic insulating layer 9, and the side surface 11a of the first resin layer 11. It is formed by that. The same surface means that the side surface 5a, the side surface 9a, and the side surface 11a constitute the same plane. Therefore, the side surface 9 a of the inorganic insulating layer 9 in the Y-axis direction of the support sheet 5 is exposed on the side surface of the laminated sheet 1. In this embodiment, the entire inorganic insulating layer 9 is the void-containing layer 91. The void-containing layer 91 contains a plurality of connected inorganic insulating particles 15 and voids formed by connecting these inorganic insulating particles 15, and the voids continue to the side surface 9 a of the inorganic insulating layer 9. ing.

  As shown in FIG. 2B, the first resin layer 11 has exposed side surfaces (hereinafter simply referred to as side surfaces) 11 a on both sides in the width direction (Y-axis direction) of the support sheet 5. The resin of the first resin layer 11 is an uncured or semi-cured resin. The first resin layer 11 may contain a plurality of inorganic fillers.

In this embodiment, since at least N and C are present as elements on the surface of the first inorganic insulating particles 15a having a particle size of 5 to 80 nm, that is, a surface treatment agent containing the elements is present, the first inorganic insulating particles 15a is strongly connected to each other through the surface treatment agent, and the second inorganic insulating particles 15b of 0.1 to 5 μm are strongly connected to each other through the joined first inorganic insulating particles 15a. The falling off of the inorganic insulating particles 15 from the side surface 9a can be reduced, and the side surface 9a of the inorganic insulating layer 9 can be prevented from collapsing. An example of the surface treatment agent is a silane coupling agent.

  Further, since C exists on the surface of the second inorganic insulating particles 15b, that is, there is a surface treatment agent containing the element, the first inorganic insulating particles 15a and the second inorganic insulating particles 15b are further subjected to both surface treatments. The second inorganic insulating particles 15b are strongly connected through the agent, or the inorganic insulating particles 15 can be further prevented from dropping off from the side surface 9a of the inorganic insulating layer 9.

  Furthermore, in the present embodiment, when the inorganic insulating layer 9 and the first resin layer 11 are laminated and integrated, even if air is caught between the inorganic insulating layer 9 and the first resin layer 11, the biting is performed. The entrained air can be discharged from the void-containing layer 91, and delamination and bubble formation at the interface between the inorganic insulating layer 9 and the first resin layer 11 can be reduced.

  Fig.3 (a) shows 2nd Embodiment of the lamination sheet 1 used for a wound body, and is a figure corresponding to FIG.2 (b). The laminated sheet 1 includes a support sheet 5, an inorganic insulating layer 9 on the support sheet 5, and a first resin layer 11 on the inorganic insulating layer 9, and a resin that constitutes the first resin layer 11. Part of the inorganic insulating layer 9 is disposed between the inorganic insulating particles 15 on the first resin layer 11 side, and the void-containing layer 91 is formed of the inorganic insulating layer 9 in which the resin of the first resin layer 11 is disposed. It is located closer to the support sheet 5 than the first portion 93. When the first resin layer 11 is laminated and integrated with the inorganic insulating layer 9, the first portion 93 is formed by connecting the resin of the first resin layer 11 to the plurality of inorganic insulating particles 15 of the inorganic insulating layer 9. It is configured to penetrate into the gap.

  In other words, the side surface in the Y-axis direction of the first portion 93 where the void-containing layer 91 of the inorganic insulating layer 9 and the resin of the inorganic insulating layer 9 are disposed is exposed, and the side surface 5a of the support sheet 5 in the Y-axis direction A side surface 9a in the Y-axis direction of the inorganic insulating layer 9 (a side surface in the Y-axis direction of the void-containing layer 91, a side surface in the Y-axis direction of the first portion 93), and a side surface 11a in the Y-axis direction of the first resin layer 11 Form the same plane.

  And also in this 2nd Embodiment, similarly to 1st Embodiment, it has the some inorganic insulation particle | grains 15 which one part mutually connected, This several inorganic insulation particle | grains 15 are 5-80 nm in particle size. The first inorganic insulating particles 15a and the second inorganic insulating particles 15b having a particle size of 0.1 to 5 μm are included, and at least N and C are present as elements on the surface of the first inorganic insulating particles 15a. C may be present on the surface of the second inorganic insulating particles 15b.

  In the second embodiment shown in FIG. 3A, the same effect as that of the first embodiment shown in FIG. 2B can be obtained. In particular, dropping of the inorganic insulating particles 15 from the side surface in the Y-axis direction of the void-containing layer 91 can be reduced. Further, the first portion 93 can improve the adhesive strength between the first resin layer 11 and the inorganic insulating layer 9.

  FIG. 3B shows a third embodiment of the laminated sheet 1 and corresponds to FIG. The part different from the configuration of FIG. 3A is that the second resin layer 13 is disposed between the support sheet 5 and the inorganic insulating layer 9, and a part of the resin constituting the second resin layer 13 is The second portion 95 is formed between the inorganic insulating particles 15 on the second resin layer 13 side of the inorganic insulating layer 9. The second portion 95 is configured such that the resin of the second resin layer 13 enters a gap formed by connecting a plurality of inorganic insulating particles 15 of the inorganic insulating layer 9. The second resin layer 13 may contain an inorganic filler.

That is, the side surfaces 11 a, 9 a, and 13 a of the first resin layer 11, the inorganic insulating layer 9, and the second resin layer 13 in the Y-axis direction of the support sheet 5 are exposed, and the void-containing layer 91 is formed of the inorganic insulating layer 9. The second resin layer 13 is located closer to the first resin layer 11 than the second portion 95 where the resin is disposed, and is located closer to the support sheet 5 than the first portion 93.

  In other words, the void-containing layer 91 of the inorganic insulating layer 9, the side surface in the Y-axis direction of the first portion 93 where the resin of the inorganic insulating layer 9 is disposed, and the second portion 95 where the resin of the second resin layer 13 is disposed. The side surface in the Y-axis direction of the support sheet 5 is exposed, the side surface 5a in the Y-axis direction of the support sheet 5, the side surface 9a in the Y-axis direction of the inorganic insulating layer 9 (the side surface in the Y-axis direction of the void-containing layer 91, the first part) 93, the side surface in the Y-axis direction of the second portion 95) and the side surface 11a in the Y-axis direction of the first resin layer 11 form the same surface.

  And also in this 3rd Embodiment, similarly to 2nd Embodiment, it has the some inorganic insulation particle | grains 15 which one part mutually connected, and this some inorganic insulation particle | grains 15 are 5-80 nm in particle size. The first inorganic insulating particles 15a and the second inorganic insulating particles 15b having a particle size of 0.1 to 5 μm are included, and at least N and C are present as elements on the surface of the first inorganic insulating particles 15a. C may be present on the surface of the second inorganic insulating particles 15b.

  Also in the third embodiment of FIG. 3B, the same effect as that of the second embodiment of FIG. 3A can be obtained. Furthermore, the adhesive strength between the first resin layer 11 and the inorganic insulating layer 9 and the adhesive strength between the second resin layer 13 and the inorganic insulating layer 9 and the support sheet 5 can be improved.

  The wound body illustrated in FIGS. 1 to 3 may include a protective film on the first resin layer 11. As the protective film, a resin film such as a PET film can be used.

  The manufacturing method of a wound body is demonstrated based on FIG. 4 using the lamination sheet of FIG.3 (b).

  (1) First, the second resin layer 13 is formed on the support sheet 5. In particular, it is desirable to use a copper foil for the support sheet 5 in that it can be used as a wiring conductor when producing a wiring board. On the other hand, examples of the support sheet other than the copper foil include various metal foils such as an aluminum foil and resin films such as a PET film.

  Specifically, a mixture of a solvent, an inorganic filler, and an uncured resin is applied to the main surface of the support sheet 5 to form a coating film for the second resin layer 13. At this time, the coating film of the second resin layer 13 is applied such that the side surface 13 a in the Y-axis direction of the second resin layer 13 is positioned on the inner side than the side surface 5 a in the Y-axis direction of the support sheet 5. The second resin layer 13 is formed by drying the coating film and evaporating the solvent. Application of the mixture can be performed using an existing molding method such as a doctor blade method, a dispenser method, a bar coater method, a die coater method, or a gravure printing method.

  (2) Next, a plurality of inorganic insulating particles 15, water or an organic solvent, and an appropriate dispersant are prepared, weighed and mixed to prepare a slurry containing the inorganic insulating particles 15.

  The first inorganic insulating particles 15a are surface-treated with a silane coupling agent containing N. Examples of the silane coupling agent containing N include a silane coupling agent having amine or amide as a functional group. By this surface treatment, N and C can be present as elements on the surface of the first inorganic insulating particles 15a.

The second inorganic insulating particles 15b are surface-treated with a silane coupling agent. As the silane coupling agent, a silane coupling agent having acrylic or methacryl as a functional group is desirable in that the effect of removing the inorganic insulating particles 15 from the inorganic insulating layer 9 is high. By this surface treatment, C can be present as an element on the surface of the second inorganic insulating particle 15b.

  The slurry contains, for example, 10% by volume or more and 60% by volume or less of inorganic insulating particles 15, and 40% by volume or more and 90% by volume or less of water or an organic solvent and a dispersing agent. The organic solvent is selected from, for example, methanol, isopropanol, n-butanol, ethylene glycol, ethylene glycol monopropyl ether, methyl ethyl ketone, methyl isobutyl ketone, xylene, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dimethylacetamide or the like. Alternatively, an organic solvent containing a mixture of two or more kinds can be used.

  Examples of the dispersant include known dispersants such as cationic, anionic and nonionic.

  (3) Next, the slurry is formed (coated) into a sheet shape on the surface of the second resin layer 13 on the support sheet 5. The slurry is applied so that the side surface 9a in the Y-axis direction of the inorganic insulating layer 9 is positioned inside the side surface 13a in the Y-axis direction of the second resin layer 13, for example. As the molding method, an existing molding method, for example, a doctor blade method, a dispenser method, a bar coater method, a die coater method, or a gravure printing method is used, and water or a solvent is removed by drying. A skeleton of the inorganic insulating layer 9 can be formed in which the two are connected in a three-dimensional network.

  (4) The first resin layer 11 is formed on the skeleton of the inorganic insulating layer 9. Specifically, first, a mixture of a solvent, an inorganic filler, and an uncured resin is applied to the main surface of the skeleton of the inorganic insulating layer 9. For example, the mixture is applied so as to cover the side surfaces 13 a and 9 a in the Y-axis direction of the second resin layer 13 and the inorganic insulating layer 9. Next, the first resin layer 11 is formed by drying the mixture and evaporating the solvent from the mixture. Application of the mixture can be performed using an existing molding method such as a doctor blade method, a dispenser method, a bar coater method, a die coater method, or a gravure printing method.

  Subsequently, a part of the first resin layer 11 (a part of the second resin part 18) enters the void of the skeleton of the inorganic insulating layer 9 to form the first resin part 16. Specifically, the support sheet 5, the skeleton of the inorganic insulating layer 9, and the first resin layer 11 are heated and pressed in the vertical direction, whereby a part of the first resin layer 11 is formed in at least a part of the voids of the inorganic insulating layer 9. (Second resin portion 18) is inserted. At this time, part of the resin of the second resin layer 13 is also allowed to enter the gap of the inorganic insulating layer 9.

  At this time, it is desirable to use a roll laminator as a heating and pressurizing device and to carry out continuously. The heating temperature of the support sheet 5 or the like is set to, for example, 60 ° C. or more and 160 ° C. or less. The pressurizing pressure of the support sheet 5 or the like is set to, for example, 0.1 MPa or more and 2 MPa or less. The heating and pressing time for the support sheet 5 or the like is set to, for example, 0.5 to 10 minutes, and when using a roll laminator, it is desirable to set the feed rate to 1 to 50 m / second. . The melt viscosity of the resin material of the first resin layer 11 during the heating time is set to 10,000 Pa · s or less, for example.

  Alternatively, on the carrier film, a first resin layer 11 is prepared by molding a mixture of the above-described solvent, filler and uncured resin into a sheet shape by the same existing molding method as described above, and this first resin layer 11 Can be placed on the inorganic insulating layer 9 of the support sheet 5 and heated and pressurized in the same manner as described above (roll lamination), so that a part of the first resin layer 11 enters the gap of the inorganic insulating layer 9. A part of the resin of the second resin layer 13 can also enter the gap of the inorganic insulating layer 9. The carrier film may function as a protective film.

  As described above, the laminated sheet 1 including the support sheet 5, the second resin layer 13, the inorganic insulating layer 9, and the first resin layer 11 is produced.

  In the laminated sheet 1 produced as described above, for example, as shown in FIG. 4, the side surface 13 a in the Y-axis direction of the second resin layer 13 is inside the side surface 5 a in the Y-axis direction of the support sheet 5. The Y-axis direction side surface 9a of the inorganic insulating layer 9 is positioned inside the Y-axis direction side surface 13a of the second resin layer 13, and the second resin layer 13 and the inorganic insulating layer 9 in the Y-axis direction. The side surfaces 13 a and 9 a are covered with the first resin layer 11.

  In such a laminated sheet, the side surfaces 13a, 9a, 11a of the second resin layer 13, the inorganic insulating layer 9, and the first resin layer 11 in the Y-axis direction on the support sheet 5 are sag by a known sheet forming method. It is inclined. Thereafter, the laminated sheet 1 is cut at a portion indicated by a one-dot chain line in FIGS. 4A and 4B, and the ear portion 10 is removed. As a result, the side surface 5a of the support sheet 5, the side surface 11a of the first resin layer 11, the side surface 13a of the second resin layer 13, and the side surface 9a of the inorganic insulating layer 9 form the same surface, as shown in FIG. The laminated sheet 1 shown can be produced. In FIG. 4B, the oblique lines indicating the cross section are omitted. The same applies to FIGS. 5B and 5C.

  Such a laminated sheet 1 is wound around the core material 3 to obtain a wound body as shown in FIG.

  The process of producing the board | substrate sheet | seat using the laminated sheet of FIG.3 (b) is demonstrated using FIG. First, a wound body of the laminated sheet 1 from which the ear portion 10 has been removed as shown in FIG. 4B is prepared, and the laminated sheet 1 is drawn out from this wound body, and a portion indicated by a one-dot chain line in FIG. To cut. That is, the board | substrate sheet | seat can be obtained by cutting the lamination sheet 1 by predetermined length.

  The substrate sheet includes a rectangular support sheet 5 having a pair of first sides and a pair of second sides opposite to each other, a second resin layer 13 disposed on the support sheet 5, and the first sheet. FIG. 5B shows a cut surface in the direction between the first sides, including the inorganic insulating layer 9 disposed on the two resin layers 13 and the first resin layer 11 disposed on the inorganic insulating layer 9; As shown in FIG. 5C, which shows a cut surface in the direction between the second sides, the four side surfaces 5 a of the support sheet 5, the four side surfaces 13 a of the second resin layer 13, and the four side surfaces 9 a of the inorganic insulating layer 9. The four side surfaces 11a of the first resin layer 11 are exposed and form the same surface. The first side is a side constituting the side surface of the support sheet 5 in the Y-axis direction, and the second side is a side orthogonal to the first side (the side in the X-axis direction (indicated by a one-dot chain line in FIG. 5A). Side)).

  Hereinafter, each member which comprises the lamination sheet 1 is demonstrated. The support sheet 5 supports the inorganic insulating layer 9, and is peeled off from the inorganic insulating layer 9 or processed into wiring when the wiring board is manufactured. The support sheet 5 is made of, for example, a flat copper foil. Since the support sheet 5 consists of copper foil, the heat resistance of the support sheet 5 can be improved.

  An inorganic insulating layer 9 is formed on the flat support sheet 5 as shown in FIG. In order to improve the adhesive force between the inorganic insulating layer 9 and the support sheet 5, a second resin layer (primer layer) 13 is formed on the main surface of the support sheet 5, and the inorganic insulating layer 9 is formed on the second resin layer 13. Is formed. The second resin layer (primer layer) 13 is not necessarily formed, but the formation of the inorganic insulating layer 9 on the support sheet 5 is facilitated by forming the second resin layer 13.

The thickness of the support sheet 5 is set to 3 μm or more and 100 μm or less, for example. The Young's modulus of the support sheet 5 is set to, for example, 70 GPa or more and 130 GPa or less. The thermal expansion coefficient of the support sheet 5 is set to, for example, 13 ppm / ° C. or more and 20 ppm / ° C. or less. The Young's modulus of the support sheet 5 is measured by a measuring method according to JISZ2280-1993 using a commercially available DMA device or the like. Moreover, the thermal expansion coefficient of the support sheet 5 is measured by a measuring method according to JISK7197-1991 using a commercially available TMA apparatus. A resin film can also be used as the support sheet 5.

  The inorganic insulating layer 9 ensures insulation between the wirings of the produced wiring board. The thickness of the inorganic insulating layer 9 is set to, for example, 1 μm or more and 15 μm or less.

  As shown in FIG. 6, the inorganic insulating layer 9 is formed of a plurality of inorganic insulating particles 15 a and 15 b (hereinafter sometimes simply referred to as 15). A plurality of inorganic insulating particles 15 are connected at a part of each other while maintaining the particle shape (concept including contact), thereby forming a three-dimensional network structure and forming a skeleton that is the main part of the inorganic insulating layer 9 Has been. Since the plurality of inorganic insulating particles 15 are connected to each other while maintaining the particle shape, there are voids between the plurality of inorganic insulating particles 15, and the first resin layer 11 of the inorganic insulating layer 9. In the gap on the side, the resin (first resin portion 16) constituting the first resin layer 11 is arranged to form the first portion 93. In FIG. 6A, the first portion 93 is described, and the void-containing layer 91 is not visible.

  Moreover, since the inorganic insulating layer 9 has a plurality of inorganic insulating particles 15 connected to each other, the rigidity of the inorganic insulating layer 9 is improved as compared with the case where a plurality of inorganic insulating particles are simply dispersed in the resin. Can be made. As a result, deformation of the inorganic insulating layer 9 can be reduced.

  The inorganic insulating particles 15 include first inorganic insulating particles 15a and second inorganic insulating particles 15b. The particle diameter of the first inorganic insulating particles 15a is set to 5 nm or more and 80 nm or less, and the particles of the second inorganic insulating particles 15b. The diameter is set to 0.1 μm or more and 5 μm or less. The particle diameters of the first inorganic insulating particles 15a and the second inorganic insulating particles 15b are, for example, that first, the cross section of the inorganic insulating layer 9 is observed with a transmission electron microscope (TEM), and particles having a particle size of 20 particles or more and 50 particles or less are obtained. It is calculated by photographing a cross section enlarged so as to include and measuring the maximum diameter of each particle in the enlarged cross section.

  For example, the first inorganic insulating particles 15 a are contained in the plurality of inorganic insulating particles 15 by 10 volume% or more and 40 volume% or less, and the second inorganic insulating particles 15 b are, for example, 55 volumes in the plurality of inorganic insulating particles 15. % Or more and 85% by volume or less. As described above, if the particle size distribution of the plurality of inorganic insulating particles 15 is set, the gap between the inorganic insulating layers 9 is prevented from becoming too small, and the resin of the first resin layer 11 and the second resin layer 13 to be described later is used. It can be made easy to enter the gap of the inorganic insulating layer 9. More desirably, the particle diameter of the first inorganic insulating particles 15a is set to 8 nm or more and 70 nm or less, and the plurality of inorganic insulating particles 15 are contained in an amount of 10% by volume to 30% by volume. The particle diameter of 15b is set to 0.15 μm or more and 2 μm or less, and the inorganic insulating particles 15 may contain 65% by volume or more and 85% by volume or less. The inorganic insulating layer 9 may contain inorganic particles other than the first inorganic insulating particles 15a and the second inorganic insulating particles 15b, and both the first inorganic insulating particles and the second inorganic insulating particles have an average particle diameter. A plurality of different particles may be used.

The inorganic insulating particles 15 form the main part (skeleton) of the inorganic insulating layer 9. The shape of the inorganic insulating particles 15 is, for example, spherical. The inorganic insulating particles 15 are made of an inorganic insulating material such as silicon oxide, aluminum oxide, titanium oxide, magnesium oxide, or zirconium oxide. The inorganic insulating particles 15 may be made of a single material or a plurality of types of materials. The inorganic insulating particles 15 are made of a material having a thermal expansion coefficient of, for example, 0.2 ppm / ° C. or more and 13 ppm / ° C. or less. The inorganic insulating particles 15 are made of a material having a Young's modulus of, for example, 10 GPa or more and 300 GPa or less. Further, the inorganic insulating layer 9 of the plurality of inorganic insulating particles 15.
The content ratio with respect to is set to, for example, 70% by volume or more, and desirably 75% by volume or more. The content of the inorganic insulating particles 15 can be determined from the area ratio in the micrograph of the cross section of the inorganic insulating layer 9.

  The 1st resin layer 11 adheres the inorganic insulating layer 9 and wiring, or the inorganic insulating layer 9 and the other inorganic insulating layer 9 laminated | stacked on this inorganic insulating layer 9 at the time of manufacture of a wiring board. For example, as shown in FIG. 6A, the first resin layer 11 includes a first resin portion 18 and an inorganic filler 20 disposed in the resin of the first resin portion 18.

  The resin of the first resin portion 18 is made of, for example, a thermosetting resin such as an epoxy resin, a bismaleimide triazine resin, a cyanate resin, a polyphenylene ether resin, a wholly aromatic polyamide resin, or a polyimide resin, and the first resin portion 18. This resin is made of a material having a thermal expansion coefficient of, for example, 30 ppm / ° C. or more and 60 ppm / ° C. or less. The first resin portion 18 is made of a material having a Young's modulus of, for example, 2 GPa or more and 10 GPa or less. As the resin (first resin portion 16) of the first portion 93, the same resin as the resin of the first resin portion 18 can be used. The resin of the first resin portion 18 and the resin of the first portion 93 are uncured or semi-cured in the laminated sheet 1.

  The thickness of the first resin layer 11 may be smaller than the thickness of the inorganic insulating layer 9. Thereby, the influence of the thermal expansion of the 1st resin layer 11 becomes small, and the inorganic insulating layer 9 can reduce the amount of thermal expansion of the 1st resin layer 11 effectively. In addition, the thickness of the 1st resin layer 11 is set to 1 to 40 micrometers, for example.

  The inorganic filler 20 made of an inorganic material improves the rigidity of the first resin layer 11 or decreases the thermal expansion coefficient. The inorganic filler 20 has a spherical shape, for example. The particle diameter of the inorganic filler 20 may be greater than or equal to the particle diameter of the second inorganic insulating particles 15b. The particle diameter of the inorganic filler 20 is set to 0.1 μm or more and 5 μm or less, for example. The content of the inorganic filler 20 with respect to the first resin layer 11 may be smaller than the content of the inorganic insulating particles 15 with respect to the inorganic insulating layer 9. The content rate with respect to the 1st resin layer 11 of the inorganic filler 20 is set to 60 volume% or less, for example.

  Next, the wiring board 24 shown in FIG. 7A manufactured using the above-described laminated sheet 1 will be described. FIG. 7A schematically shows a cross section of the wiring board 24 cut in the vertical direction.

  The wiring board 24 is used for electronic devices such as various audiovisual devices, home appliances, communication devices, computer devices or peripheral devices thereof. The wiring substrate 24 is, for example, a build-up multilayer wiring substrate, and includes a core substrate 25 and a pair of wiring layers 26 formed above and below the core substrate 25 as shown in FIG.

  The core board 25 is intended to enhance the rigidity of the wiring board 26 and to conduct between the pair of wiring layers 26. The core substrate 25 includes a resin base 27, a cylindrical through-hole conductor 28 formed through the resin base 27 in the vertical direction, and a columnar insulator disposed in a region surrounded by the through-hole conductor 28. 29.

  The resin base 27 increases the rigidity of the core substrate 25. The resin substrate 27 includes, for example, a resin, a base material coated with the resin, and an inorganic insulating filler.

The resin contained in the resin substrate 27 forms the main part of the resin substrate 27. Examples of this resin include epoxy resins, bismaleimide triazine resins, cyanate resins, polyparaphenylene benzbisoxazole resins, wholly aromatic polyamide resins, polyimide resins, aromatic liquid crystal polyester resins, polyether ether ketone resins or polyether ketone resins. Made of resin material.

  The base material contained in the resin base 27 is to make the resin base 27 highly rigid and low in thermal expansion. This base material consists of what arranged the woven fabric or nonwoven fabric comprised by the fiber, or the fiber in one direction. Moreover, this fiber consists of glass fiber or resin fiber, for example.

  The inorganic insulating filler contained in the resin base 27 makes the resin base 27 highly rigid and low in thermal expansion. The inorganic insulating filler is composed of a plurality of particles made of an inorganic insulating material such as silicon oxide, aluminum oxide, aluminum nitride, aluminum hydroxide, or calcium carbonate.

  The through-hole conductor 28 is for electrically connecting the upper and lower wiring layers 26 of the core substrate 25. The through-hole conductor 28 is made of a conductive material such as copper, silver, gold, aluminum, nickel, or chromium.

  The insulator 29 forms a support surface of a via conductor 30 described later. The insulator 29 is made of a resin material such as polyimide resin, acrylic resin, epoxy resin, cyanate resin, fluororesin, silicon resin, polyphenylene ether resin, or bismaleimide triazine resin.

  On the other hand, a pair of wiring layers 26 are formed above and below the core substrate 25 as described above. The wiring layer 26 is formed in the via hole and the inorganic insulating layer 9 in which the via hole along the thickness direction is formed, the wiring 31 partially formed on the resin substrate 27 or on the inorganic insulating layer 9, and the via hole. Via conductor 30 is included.

  The wiring layer 26 includes a first resin layer 11 positioned on the core substrate 25 side, an inorganic insulating layer 9 stacked on the first resin layer 11, and a second stacked on the inorganic insulating layer 9. And a resin layer 13. In addition, the inorganic insulating layer 9, the 1st resin layer 11, and the 2nd resin layer 13 are what the laminated sheet 1 mentioned above was equipped with. Further, in the wound body and the substrate sheet, the first resin portion 16 of the inorganic insulating layer 9 and the second resin portion 18 of the first and second resin layers 11 and 13 were uncured or semi-cured. In the substrate 24, the first resin portion 16 and the second resin portion 18 are cured.

  The first resin layer 11 adheres the resin base 27 and the inorganic insulating layer 9 or adheres the laminated inorganic insulating layers 9 to each other while adhering to the side surface and upper surface of the wiring 31 on the surface of the core substrate 25. . The inorganic insulating layer 9 constitutes a main part of the inorganic insulating layer 9 and functions as an insulating member between the wirings 31 arranged apart along the thickness direction. Since the inorganic insulating layer 9 has a low coefficient of thermal expansion and high rigidity compared to the resin material, the coefficient of thermal expansion in the planar direction of the inorganic insulating layer 9 can be reduced. Therefore, the difference in thermal expansion coefficient in the planar direction between the wiring board 24 and an electronic component (not shown) mounted on the wiring board 24 can be reduced, and thus the warping of the wiring board 24 can be reduced.

  The wirings 31 are arranged away from each other along the planar direction or the thickness direction, and function as grounding wirings, power supply wirings, or signal wirings. The wiring 31 is made of a conductive material such as copper, silver, gold, aluminum, nickel, or chromium. The thickness of the wiring 31 is set to 3 μm or more and 20 μm or less, for example. The coefficient of thermal expansion of the wiring 31 is set to, for example, 14 ppm / ° C. or more and 19 ppm / ° C. or less. The L / S (line / space) of the wiring 31 is set to, for example, 3/3 μm or more and 40/40 μm or less.

The via conductor 30 electrically connects the wirings 31 that are spaced apart from each other in the thickness direction, and is formed in a columnar shape that becomes narrower toward the core substrate 25. The via conductor 30 is made of, for example, a conductive material such as copper, silver, gold, aluminum, nickel, or chromium. The via conductor 30 has a coefficient of thermal expansion set to, for example, 14 ppm / ° C. or more and 19 ppm / ° C. or less.

  Accordingly, the wiring substrate 24 of the present disclosure includes the first resin layer 11, the inorganic insulating layer 9 disposed on the first resin layer 11, and the wiring 31 disposed on the inorganic insulating layer 9. The inorganic insulating layer 9 includes a plurality of inorganic insulating particles 15 that are partially connected to each other, and a first resin portion 16 that is disposed between the plurality of inorganic insulating particles 15. In addition, the plurality of inorganic insulating particles 15 include first inorganic insulating particles 15a having a particle diameter of 5 to 80 nm and second inorganic insulating particles 15b having a particle diameter of 0.1 to 5 μm, and the first inorganic insulating particles 15a. At least N and C are present as elements on the surface.

  A method for manufacturing the wiring board 24 using the wound body of the present disclosure will be described with reference to FIGS. FIG. 7B to FIG. 8 are cross-sectional views illustrating one process of a method for manufacturing a wiring board manufactured using the wound body of the present disclosure.

  (1) First, the laminated sheet 1 having a predetermined length is drawn out from the wound body configured as described above, cut to a predetermined length, and a substrate sheet 35 having a predetermined length is prepared.

  (2) The core substrate 25 (substrate) is produced. For production of the core substrate 25, first, for example, a resin substrate 27 in which a plurality of resin layers are laminated on a metal foil is formed. Next, after a through hole is formed in the resin base 27 by, for example, drilling or laser processing, a cylindrical shape is formed on the inner wall of the through hole by, for example, electroless plating, electroplating, vapor deposition, CVD, or sputtering. A through-hole conductor 28 is formed. Next, an insulator 29 is formed by filling a region surrounded by the through-hole conductor 28 with a resin material. After the conductive material is deposited on the exposed portion of the insulator 29, a conventionally known photolithography technique or etching is used. The wiring 31 is formed by patterning with the above. The core substrate 25 is prepared as described above.

  (3) As shown in FIGS. 7B and 8A, the produced substrate sheet 35 is laminated on the core substrate 25. Specifically, the lamination of the substrate sheet 35 is performed so that the first resin layer 11 of the substrate sheet 35 is in contact with the core substrate 25.

  Thereafter, in order to integrate the substrate sheet 35 and the core substrate 25, heat and pressure are applied in the vertical direction in a vacuum state, and a part of the resin of the first resin layer 11 is formed in the voids of the void-containing layer 92 of the inorganic insulating layer 9. Get in. At this time, a part of the resin of the second resin layer 13 may also enter the void of the void-containing layer 92 of the inorganic insulating layer 9. At this time, it is desirable to adjust the heating and pressing conditions so that the resin enters almost all the voids of the inorganic insulating layer 9 in order to ensure the insulation reliability.

  At this time, the air in the inorganic insulating layer 9 can be easily extracted from the side surface 9a of the void-containing layer 91 through the voids in the void-containing layer 91, so that the voids in the inorganic insulating layer 9 can be almost eliminated. It is possible to eliminate problems such as peeling in the wiring board manufacturing process.

  The heating temperature is set to, for example, 60 ° C. or more and 160 ° C. or less, and the pressurizing pressure is set, for example, to 0.1 MPa or more and 4 MPa or less. The heating and pressing time for the support sheet 5 or the like is set to, for example, not less than 0.5 minutes and not more than 180 minutes.

(4) By heating the substrate sheet 35 and the core substrate 25 at a temperature equal to or higher than the thermosetting start temperature of the resin of the first resin layer 11 and the resin of the second resin layer 13, the uncured state in the substrate sheet 35 is obtained. The resin is thermally cured to form the substrate sheet 35 as the wiring layer 26. The heating temperature of the substrate sheet 35 or the like is set to, for example, 80 ° C. or more and 250 ° C. or less.

  In addition, the thermosetting of the resin may be performed simultaneously with the heating and pressurization in the above-described step (3).

  (5) As shown in FIG.8 (b), the through-hole which penetrates the inorganic insulating layer 9, the 1st resin layer 11, and the 2nd resin layer 13 from the surface of the support sheet 5 in the thickness direction is formed. The through hole is formed by irradiating the upper surface of the support sheet 5 with laser light using, for example, a YAG laser device or a carbon dioxide gas laser device.

  (6) Next, in order to remove the resin residue (smear) generated by laser processing at the bottom of the above-described through hole, a strong alkali treatment (desmear treatment) is performed. As the strong alkaline aqueous solution, for example, an aqueous solution of potassium permanganate or sodium permanganate is suitable.

  In this embodiment, the first inorganic insulating particles 15a are strongly connected to each other by N and C on the surface of the first inorganic insulating particles 15a, and the desmear liquid in the desmear treatment enters between the first inorganic insulating particles 15a. It can suppress and can melt | dissolve the 1st inorganic insulating particle 15a. Thereby, at the time of the desmear process at the time of forming a through-hole, the connection cancellation | release of 1st inorganic insulating particles 15a can be suppressed, and the inner wall surface collapse of a through-hole can be suppressed.

  (7) The via conductor 30 is formed in the through hole. The via conductor 30 is formed by filling a conductive material in the through hole using, for example, electroless plating, vapor deposition, CVD, or sputtering.

  (8) The wiring is formed by patterning the support sheet 5 made of copper foil using, for example, a photolithography technique or the like.

  In addition, when not using copper foil for the support sheet 5, the support sheet 5 is peeled by the process of the above-mentioned (7), and when forming a via conductor at the process of (7), the insulating layer surface After a conductive material is deposited on the entire surface, wiring is formed by performing the above-described patterning. As described above, the wiring substrate 24 as shown in FIG. 7A is manufactured.

  An electronic component is arranged on the upper surface of the wiring board 24 formed in this way, and the electronic component is mounted on the wiring 31 via a bonding member such as a bump or solder, thereby producing a mounting structure.

  The present disclosure is not limited to the above-described embodiments, and various changes, improvements, combinations, and the like can be made without departing from the scope of the present disclosure.

  In the embodiment of the wiring substrate 24 described above, the configuration in which one inorganic insulating layer 9 is stacked has been described as an example, but any number of inorganic insulating layers 9 may be stacked.

  Average particle surface-treated with a silane coupling agent containing 15% by volume of silica (first inorganic insulating particles 15a) having an average particle diameter of 20 nm and surface-treated with a silane coupling agent containing amine as a functional group and acrylic as a functional group A volume of 1.0 μm of silica (second inorganic insulating particles 15b) was prepared in an amount of 85% by volume, and this was mixed with MEK (methyl ethyl ketone) and a dispersant as a solvent to prepare a slurry.

This slurry was shaped and dried on the surface of a support sheet made of a copper foil having a thickness of 18 μm so as to have a thickness of 5 μm by using a doctor blade method, thereby preparing a skeleton of the inorganic insulating layer.

  On the other hand, on the PET film, a coating film to be a first resin layer containing a thermosetting epoxy resin as a main component is formed, placed on the inorganic insulating layer, and laminated and integrated with a roll laminator. Then, a laminated sheet on which the inorganic insulating layer and the first resin layer were formed was formed, the ear portion was cut, and a laminated sheet of the present invention as shown in FIG.

  On the other hand, the present invention is used except that the first inorganic insulating particles 15a surface-treated with a silane coupling agent containing acrylic as a functional group and the second inorganic insulating particles 15b surface-treated with a silane coupling agent containing acrylic as a functional group are used. The laminated sheet of the comparative example was produced in the same manner as the laminated sheet.

  As a result of analyzing the element on the particle surface in the laminated sheet of the present invention using an energy dispersive X-ray analyzer (EDS) attached to a transmission electron microscope (TEM), N and C are formed on the surface of the first inorganic insulating particle 15a. C is present on the surface of the second inorganic insulating particles 15b. In the laminated sheet of the comparative example, C is present on the surface of the first inorganic insulating particles 15a, and C is also present on the surface of the second inorganic insulating particles 15b. Existed.

  As a result of observing the falling state of the inorganic insulating particles on the side surface of the inorganic insulating layer of the laminated sheet using 20 scanning electron microscopes (SEM), the laminated sheet of the present invention has voids due to the dropping of the second inorganic insulating particles, The maximum length of the gap was 5% or less with respect to the thickness of the inorganic insulating layer, whereas the laminated sheet of the comparative example exceeded 20%.

  Furthermore, in the step of producing a wiring board using the laminated sheet, a through-hole penetrating the inorganic insulating layer 9 and the first resin layer 11 in the thickness direction from the surface of the support sheet 5 is formed with a carbon dioxide laser device, In order to remove the resin residue (smear) generated by laser processing at the bottom of the through hole, a strong alkali treatment (desmear treatment) using a sodium permanganate solution is performed at 70 ° C. for 5 minutes, and 20 penetrations The state of the inner wall surface of the hole was observed using SEM.

  In the product of the present invention, the step between the inorganic insulating layer and the resin layer formed by the collapse of the inner wall surface of the through hole during the desmear treatment (the portion where the inner wall surface of the inorganic insulating layer is retracted from the inner wall surface of the resin layer) is not observed. On the other hand, in the comparative product, the step was observed for 80% or more of the through holes.

DESCRIPTION OF SYMBOLS 1 Laminated sheet 5 Support sheet 9 Inorganic insulating layer 91 Space | gap content layer 93 1st part 95 2nd part 11 1st resin layer 13 2nd resin layer 15 Inorganic insulating particle 24 Wiring board

Claims (10)

  A long laminated sheet has a winding structure wound in the length direction, the laminated sheet comprising a long supporting sheet, an inorganic insulating layer disposed on the supporting sheet, A first resin layer disposed on the inorganic insulating layer, the side surfaces of the inorganic insulating layer in the width direction of the support sheet are exposed, and the inorganic insulating layers are partially connected to each other. A plurality of inorganic insulating particles, the plurality of inorganic insulating particles including first inorganic insulating particles having a particle size of 5 to 80 nm and second inorganic insulating particles having a particle size of 0.1 to 5 μm, A wound body comprising at least N and C as elements on the surface of the first inorganic insulating particles.   The wound body according to claim 1, wherein C is present as an element on a surface of the second inorganic insulating particle.   The winding according to claim 1 or 2, wherein the inorganic insulating layer has a void-containing layer in which voids are formed between inorganic insulating particles, and a side surface of the void-containing layer in the width direction of the support sheet is exposed. Round body.   The wound body according to any one of claims 1 to 3, wherein an amine or an amide is included as a functional group on a surface of the first inorganic insulating particle.   The wound body according to any one of claims 1 to 4, wherein at least acrylic or methacryl is present as a functional group on the surface of the second inorganic insulating particle.   The main surface has a rectangular shape having a pair of first sides and a pair of second sides facing each other, a support sheet, an inorganic insulating layer disposed on the support sheet, and a second disposed on the inorganic insulating layer. 1 resin layer, and the side surface of the inorganic insulating layer in the width direction of the support sheet is exposed, the inorganic insulating layer has a plurality of inorganic insulating particles connected to each other, The plurality of inorganic insulating particles include first inorganic insulating particles having a particle size of 5 to 80 nm and second inorganic insulating particles having a particle size of 0.1 to 5 μm, and the surface of the first inorganic insulating particles is an element. A substrate sheet, wherein at least N and C are present.   The substrate sheet according to claim 6, wherein at least C is present as an element on a surface of the second inorganic insulating particle.   A wiring board comprising a first resin layer, an inorganic insulating layer disposed on the first resin layer, and a wiring disposed on the inorganic insulating layer, wherein the inorganic insulating layers are mutually The plurality of inorganic insulating particles partially connected to each other and the first resin portion disposed between the plurality of inorganic insulating particles, and the plurality of inorganic insulating particles have a particle size of 5 to 80 nm. A wiring board comprising: 1 inorganic insulating particle; and second inorganic insulating particle having a particle size of 0.1 to 5 μm, wherein at least N and C are present as elements on the surface of the first inorganic insulating particle.   The wiring board according to claim 8, further comprising a via conductor that penetrates the first resin layer, the inorganic insulating layer, and the wiring in a thickness direction.   A mounting structure comprising: the wiring board according to claim 8; and an electronic component mounted on the wiring board and electrically connected to the wiring.

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