JP2010016301A - Interlayer connecting member for multilayer printed wiring board, method for manufacturing the interlayer connecting member, the multilayer printed wiring board and method for manufacturing the multilayer printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an interlayer connecting member of a multilayer printed wiring board which is high in the positioning accuracy of a metal ball, without producing a residue and the like due to drilling and laser processing which is not influenced by heat in processing, ad to provide its manufacturing method, a multilayer printed wiring board and its manufacturing method. <P>SOLUTION: This interlayer connecting member 10 of a multilayer printed wiring board 30 includes a plurality of layers of circuit patterns and electrodes 28, 38. The interlayer connecting member is further provided with: an insulating resin sheet 12 of a thermosetting resin; hole parts 24 formed at predetermined positions of the resin sheet 12; and identical balls 14, stored in the hole parts 24 and each having a diameter larger than the thickness of the resin sheet 12. The hole part 24 is formed, by heating the resin sheet 12 into a semi-cured state and sticking a projecting member 22 into a predetermined position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an interlayer connection member of a multilayer printed wiring board in which a metal ball is interposed between the layers as an interlayer connection member for conducting between the conductor pattern layers of the printed wiring board having a plurality of conductor pattern layers. The present invention relates to a multilayer printed wiring board and a manufacturing method thereof.

  In recent years, as disclosed in, for example, Patent Documents 1 and 2, as a connection structure for achieving conduction between a plurality of conductor pattern layers of a multilayer printed wiring board including a double-sided wiring board, metal balls are interposed between the layers. There is a printed wiring board that aims at conduction.

  An interlayer connection member of a multilayer printed wiring board disclosed in Patent Document 1 is a method of embedding metal spheres in a resin sheet by arranging a flat mask having a through hole at a predetermined position on the resin sheet, The positioning is performed by casting a metal ball into the hole and positioning it, and then pushing the metal ball into the resin sheet.

The interlayer connection structure disclosed in Patent Document 2 is obtained by inserting a conductor made of a metal sphere having a size equal to or larger than the thickness of the insulating adhesive layer into the via hole. The metal spheres are arranged in the via hole by sucking the insulating adhesive layer in which the via hole is formed by drilling or laser processing through the porous ceramic material, and further sucking the metal sphere through the insulating adhesive layer. A metal ball is sucked in.
JP 2006-332324 A JP 2001-77497 A

  However, in the case of the connection structure between the conductor pattern layers disclosed in Patent Document 1, the through hole of the mask requires a slight clearance for passing through the metal sphere, and further, the position in the direction of the substrate surface when the metal sphere is pushed in. Deviation occurs, the positioning accuracy of the metal sphere is limited, and it cannot be applied to a multilayer printed wiring board in which wiring patterns are formed at high density.

  In the case of the connection structure disclosed in Patent Document 2, residues and burrs are likely to occur in the via hole due to drilling or laser processing. When the insulating adhesive layer is a thermosetting resin, the peripheral insulating adhesion is caused by heat during processing. There was a possibility that the layer was partially cured, resulting in a decrease in adhesion and distortion in the front and back conductors.

  The present invention has been made in view of the above-described background art, and has high accuracy in positioning metal balls, does not generate residues due to drilling or laser processing, and is not affected by heat during processing. It is an object of the present invention to provide a connecting member and a manufacturing method thereof, a multilayer printed wiring board and a manufacturing method thereof.

  The present invention is an interlayer connection member for conducting electrical conduction between the respective conductive pattern layers of a multilayer printed wiring board having a conductive pattern layer such as a plurality of circuit patterns and electrodes, and an insulating adhesive layer made of an insulating resin; It is an interlayer connection member provided with a hole formed at a predetermined position of the insulating adhesive layer and a metal sphere accommodated in the hole and having a diameter larger than the thickness of the insulating adhesive layer.

  The present invention also relates to a method for manufacturing an interlayer connection member for conducting electrical conduction between each conductive pattern layer of a multilayer printed wiring board provided with a conductive pattern layer such as a plurality of circuit patterns and electrodes, and comprising an insulating adhesive made of an insulating resin A method of manufacturing an interlayer connection member comprising: forming a hole at a predetermined position of a layer; and disposing a metal sphere having a diameter larger than the thickness of the insulating adhesive layer in the hole and fixing the ball together with the conductor pattern It is.

  The insulating adhesive layer is a thermosetting resin such as an epoxy resin, and the hole is formed by heating the insulating adhesive layer in a semi-cured state and piercing a convex member at a predetermined position of the insulating adhesive layer. . The temperature of the insulating adhesive layer and the temperature of the convex member during the heating are lower than the curing start temperature of the thermosetting resin. Further, in a state where the convex member is stabbed into the insulating adhesive layer, there is a slight gap between the convex member and the lower layer member of the insulating adhesive layer, and the resin of the insulating adhesive layer remains on the bottom of the hole. Forming the hole.

  Further, according to the present invention, an insulating adhesive layer made of an insulating resin is laminated on an electrode of the conductive pattern layer of one wiring board on which a plurality of layers of circuit patterns and conductive pattern layers such as electrodes are formed, and the insulating adhesive layer A multi-layer print in which a metal sphere is disposed in a hole formed at a predetermined position, and an electrode in contact with the metal sphere is formed in an annular shape and a part of the ring is cut to form a slit. It is a wiring board.

  The present invention also includes a step of laminating an insulating adhesive layer made of an insulating resin on the conductor pattern layer of one wiring board on which a plurality of layers of circuit patterns and conductive pattern layers such as electrodes are formed, and the insulating adhesive layer. A step of forming a hole at a predetermined position, a step of arranging a metal sphere in the hole, and the electrode of the other wiring board provided with an electrode in contact with the metal sphere, facing the metal sphere, A method of manufacturing a multilayer printed wiring board comprising the step of laminating and fixing the other wiring board on the insulating adhesive layer.

  According to the multilayer printed wiring board interlayer connection member and the manufacturing method thereof of the present invention and the multilayer printed wiring board and the manufacturing method thereof, the positioning accuracy of the metal spheres for connecting between the conductive pattern layers is high, and the insulating adhesive layer is also processed. Residue due to heat does not occur, and there is no influence of heat during processing.

  In addition, it is possible to provide a highly reliable multilayer printed wiring board with reliable bonding between the electrode of the conductor pattern layer and the metal sphere. Furthermore, the electrode shape can also be reduced, the connection pitch can be narrowed and it can be easily made into a fine pattern, high-density wiring can be easily made, and the electronic apparatus can be reduced in size.

  In particular, in the case of a multilayer printed wiring board in which slits are formed in the electrodes, the resin remaining in the electrodes can be surely pushed out, and the connection between the metal sphere and the electrodes becomes more reliable, and electrical reliability is improved. A high multilayer printed wiring board can be formed.

  Hereinafter, an embodiment of an interlayer connection member of a multilayer printed wiring board according to the present invention will be described with reference to FIG. The interlayer connection member 10 of the multilayer printed wiring board of this embodiment is formed of a thermosetting resin such as an epoxy resin or a phenol resin, as shown in FIG. A copper ball 14, which is a metal sphere, is embedded in the resin sheet 12. The diameter of the copper ball 14 is set to 120 μm, for example, which is larger than the thickness of the resin sheet 12, and a part of the copper ball 14 is exposed on both surfaces of the resin sheet 12. The surface of the copper ball 14 is provided with a solder plating 16 such as Sn-Ag. The position of the copper ball 14 corresponds to the electrode position of the multilayer printed wiring board to be laminated.

  The resin sheet 12 is provided so that release films 18 and 19 having good peelability are attached to both surfaces so that dust or the like does not adhere to the resin sheet 12.

  Next, the manufacturing method of the interlayer connection member 10 of the multilayer printed wiring board of this embodiment is demonstrated based on FIG. The method for manufacturing the interlayer connection member 10 is first in a semi-cured state via a release film 18 on a hot plate 20 such as a metal plate heated to 100 ° C., for example, as shown in FIG. A resin sheet 12 of a thermosetting resin in a B stage state is placed. Next, as shown in FIG. 1 (b), a convex member 22 is arranged and inserted into a predetermined position of the resin sheet 12 which is an insulating adhesive layer, and the softened resin sheet 12 as shown in FIG. 1 (c). The hole 24 by the convex member 22 is formed at a predetermined position. The position of the convex member 22 corresponds to the electrode position of a multilayer printed wiring board to be formed later. In addition, in a state where the convex member 22 is pierced into the resin sheet 12, a slight gap is provided between the lower layer of the resin sheet 12 and the resin of the resin sheet 12 slightly on the bottom surface of the hole 24. The hole 24 is formed so as to remain. Thereby, the dent etc. of the convex member 22 do not remain in the lower layer member of the resin sheet 12.

  Thereafter, as shown in FIG. 1 (d), the copper ball 14 is disposed in the hole 24. Thereby, the copper ball 14 easily enters the hole 24 and is positioned reliably. The copper ball 14 is arranged in advance by sucking the copper ball 14 into a metal plate or the like having a suction port arranged in the same manner as the hole 24 and placing the copper ball 24 above the hole 24 in the sucked state. When the suction is released, the copper ball 14 may fall into the hole 24 and be positioned. Alternatively, the copper ball 14 may be dropped into the hole 24 from a mask having holes with the same arrangement as the hole 24.

Next, as shown in FIG. 1 (e), a release film 19 is placed on the copper ball 14 on the surface of the resin sheet 12, and a pressure of 1 kg / cm ² , a temperature of 100, for example, is applied from the release film 19 to the hot plate 21. Hot press at 30 ° C. for 30 seconds. Thereby, the copper ball 14 is pushed and embedded in the resin of the resin sheet 12, and the interlayer connection member 10 is formed as shown in FIG. 1 (f).

  Next, a usage example of the interlayer connection member 10 of this embodiment will be described with reference to FIG. First, one release film 18 is peeled off, and as shown in FIG. 2 (a), the copper ball 14 is placed on one single-sided wiring board 26 of a double-sided printed wiring board that conducts between the conductive pattern layers of the circuit pattern. . On the single-sided wiring board 26, electrodes 28 connected to the copper balls 14 are formed at predetermined positions on the surface of the insulating substrate 25.

As shown in FIG. 2B, the single-sided wiring board 26 is placed on a hot plate 32 heated to 100 ° C., for example, and heats the resin sheet 12. Thereafter, as shown in FIG. 2 (c), the release sheet 19 is peeled off, and the other single-area layer substrate 36 is overlaid as shown in FIG. 2 (d). At this time, the electrode 38 of the single area layer substrate 36 contacts the copper ball 14. Thereafter, as shown in FIG. 2 (e), for example, a vacuum press is performed at 170 ° C. and a pressure of 15 kg / cm ² for 5 minutes. In this state, the copper ball 14 is connected to the electrodes 28 and 38 at a predetermined position between the insulating substrates 25 and 35 constituting the single area layer substrates 26 and 36. Thus, a substrate having a double-sided wiring structure as shown in FIG. Then, the double-sided printed wiring board 30 is taken out from the press machine, and further after-curing is performed at 170 ° C. for 60 minutes to cure the resin reliably.

  At this time, as shown in FIG. 2 (e), the copper ball 14 is crushed into an elliptical cross section. The crushing ratio is preferably about 5% to 70% of the diameter of the copper ball 14. If the compression ratio is 5% or less, the contact area of the upper and lower wirings is small, the connection is insufficient, and if the compression ratio is 70% or more, the crushed copper balls 14 spread on both sides of the pattern. This is because there is a risk of short circuit with the piping to be performed. As described above, a double-sided printed wiring board 30 as shown in FIG.

  According to the interlayer connection member of the multilayer printed wiring board of this embodiment, the manufacturing method thereof, and the manufacturing method of the multilayer printed wiring board, the positioning accuracy of the copper ball 14 that is a metal ball is accurately performed by the hole 24. Further, no residue or the like due to the processing of the hole 24 is generated, and there is no influence of heat during processing.

  In addition, the electrode area of each layer can be reduced, and space can be saved in the electronic device, which contributes to downsizing of electronic devices such as mobile phones. In particular, since the connection pitch can be 0.4 mm or less, a high-density wiring material can be connected. Further, since the connection with the electrode is a connection by plastic flow of the metal with the copper ball 14, the conduction resistance can be lowered and a large current can flow. Furthermore, the connection with each conductor pattern layer can be reliably connected with one conductor of the copper ball 14 between the electrodes of the circuit pattern, and compared with the case of using an anisotropic conductor adhesive, The risk of migration is small and it can be used for high-density wiring boards.

  Next, another embodiment of the multilayer printed wiring board of the present invention will be described with reference to FIG. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the multilayer printed wiring board 40 of this embodiment, as shown in FIG. 3 (h), the resin sheet 12 is laminated between a pair of single-sided wiring boards 42 and 44, and circuit patterns and electrodes are placed on the single-sided wiring boards 42 and 44. Conductive pattern layers 43 and 45 are formed, and the electrodes 46 and 48 of the conductive pattern layers 43 and 45 are electrically connected by the copper balls 14.

  Here, the electrode 46 formed on the single-sided wiring board 42 is formed in a C shape as shown in the right view of FIG. 3B, and a slit 46a is formed on the side. This is because, as will be described later, when the resin sheets 12 are laminated, the C-shaped inner resin is easily pushed out to the side by the copper balls 14 so that the connection between the copper balls 14 and the electrodes 46 is ensured. To do.

  Next, the manufacturing method of the multilayer printed wiring board 40 of this embodiment is demonstrated. First, the copper foil 41 of the single-sided wiring board 42 shown in FIG. 3A is etched to form a predetermined circuit pattern and a conductor pattern layer 43 of the electrode 46 as shown in FIG. At this time, the electrode 46 of the conductor pattern layer 43 is formed in a C shape as shown in the right figure of FIG. 3B, and a part of the ring is removed to form a slit 46a.

  Thereafter, as shown in FIG. 3C, a resin sheet 12 of a thermosetting resin such as a semi-cured B stage epoxy resin is disposed on the conductor pattern layer 43 of the single-sided wiring board 42, and a release sheet. 49 and laminated together. The temperature of the resin sheet 12 at this time is laminated at a roll temperature of 100 ° C., for example. Thereafter, as shown in FIG. 3 (d), the release sheet 49 is peeled off, and the convex member 22 is disposed at a predetermined position of the resin sheet 12 that is an insulating adhesive layer, and as shown in FIG. 3 (e), The convex member 22 is pierced at a predetermined position of the softened resin sheet 12 to form a hole 24 as shown in FIG. At this time, in a state where the convex member 22 is pierced into the resin sheet 12, a slight gap is provided between the lower surface of the resin sheet 12 and the single-sided wiring substrate 42, and the resin of the resin sheet 12 is placed on the bottom surface of the hole 24. The hole 24 is formed so as to remain slightly.

  Next, as shown in FIG. 3G, the copper ball 14 is placed in the hole 24. Thereby, the copper ball 14 easily enters the hole 24 and is positioned reliably. As described above, the copper ball 14 is placed in advance by sucking the copper ball 24 into a metal plate or the like having a suction port arranged in the same manner as the hole 24 and sucking the copper ball above the hole 24 in the sucked state. It is preferable that the copper ball 14 is positioned in the hole portion 24 when the suction is released by positioning the position 24. Alternatively, the copper ball 14 may be dropped into the hole 24 from a mask having holes with the same arrangement as the hole 24.

Next, the other single area layer substrate 44 is overlaid on the copper ball 14 of the resin sheet 12. Also at this time, the copper ball 14 is in contact with the electrode 48 at a predetermined position of the single area layer substrate 44. In this state, after aligning the upper and lower substrates from above the one-area layer substrate 44, vacuum pressing is performed, for example, at 170 ° C. and a pressure of 15 kg / cm ² for 5 minutes using a hot press machine. In this state, the copper ball 14 contacts the electrodes 46 and 48 at a predetermined position between the single area layer substrates 42 and 44. Thereby, a substrate having a double-sided wiring configuration as shown in FIG. And the double-sided printed wiring board 40 which is a multilayer printed wiring board was taken out from the press machine, for example, after-curing for 60 minutes at 170 degreeC, and resin was hardened | cured reliably.

  At this time, in the electrode 46, when the resin sheet 12 is laminated, the C-shaped inner resin is easily pushed out from the slit 46a to the side by the copper ball 14, and the connection between the copper ball 14 and the electrode 46 is ensured. Done. Further, the copper ball 14 is crushed into an elliptical cross section, and the crushed ratio is preferably about 5% to 70% of the diameter of the copper ball 14.

  According to the multilayer printed wiring board and the manufacturing method thereof of this embodiment, the same effect as that of the above embodiment can be obtained. Further, in the connection between the copper ball 14 and the electrode 46, the resin of the resin sheet 12 is the electrode 46. Thus, the metal connection between the copper ball 14 and the electrode 46 is not hindered and the electrical connection is ensured. Further, in a state where the convex member 22 is stabbed into the resin sheet 12, there is a slight gap between the resin sheet 12 and the single-sided wiring board 42 under the resin sheet 12, and the resin of the resin sheet 12 is slightly on the bottom surface of the hole 24. Therefore, the lower single-sided wiring board 42 is not damaged or distorted. In the electrode 46, the resin remaining inside the C-shape when the hole 24 is formed is easily pushed out from the slit 46a to the side by the copper ball 14, and the electrical connection is reliably achieved.

  The interlayer connection member of the multilayer printed wiring board of the present invention and the manufacturing method thereof and the multilayer printed wiring board and the manufacturing method thereof are not limited to the above embodiment, and may be a multilayer board other than the double-sided printed wiring board, A multilayer printed wiring board provided with three or more conductor pattern layers may be used. The metal sphere may also be a metal particle other than a copper ball or a solder ball, and the material can be selected as appropriate, and the surface may be subjected to solder plating other than Sn-Ag.

  Further, the thickness of the insulating adhesive layer is thinner than the diameter of the metal sphere, and may be 50% or more of the metal sphere, and can be set as appropriate. As for the shape of the electrode, two or more slits may be formed in addition to the C-shape.

It is a schematic longitudinal cross-sectional view which shows the manufacturing process of the correlation connection member of the multilayer printed wiring board of one Embodiment of this invention. It is a schematic longitudinal cross-sectional view which shows the manufacturing process of the multilayer printed wiring board of one Embodiment of this invention. It is a schematic longitudinal cross-sectional view which shows the manufacturing process of the multilayer printed wiring board of other embodiment of this invention.

Explanation of symbols

10 Interlayer connecting member 12 Resin sheet 14 Copper ball 16 Solder plating 18, 19, 49 Peeling film 22 Convex member 24 Hole 24
26, 36, 42, 44 Single-sided wiring board 30, 40 Double-sided printed wiring board 43, 45 Conductor pattern layer

Claims (7)

  In an interlayer connection member for conducting electrical conduction between the conductor pattern layers of a multilayer printed wiring board having a plurality of conductor pattern layers, an insulating adhesive layer made of an insulating resin, and a hole formed at a predetermined position of the insulating adhesive layer And an interlayer connection member comprising a metal sphere accommodated in the hole and having a diameter larger than the thickness of the insulating adhesive layer.   Forming a hole at a predetermined position of an insulating adhesive layer made of an insulating resin in a method of manufacturing an interlayer connection member that conducts conduction between each conductive pattern layer of a multilayer printed wiring board having a plurality of conductive pattern layers; and A method of manufacturing an interlayer connection member, comprising: placing a metal ball having a diameter larger than the thickness of the insulating adhesive layer in the hole and fixing the ball together with the conductor pattern.   The insulating adhesive layer is a thermosetting resin, and the hole is formed by heating the insulating adhesive layer in a semi-cured state and piercing a convex member at a predetermined position of the insulating adhesive layer. The method for manufacturing an interlayer connection member according to claim 2.   4. The method for producing an interlayer connection member according to claim 3, wherein the temperature of the insulating adhesive layer and the temperature of the convex member at the time of heating are lower than the curing start temperature of the thermosetting resin. .   In a state where the convex member is pierced into the insulating adhesive layer, the insulating adhesive layer is slightly spaced from the member below the insulating adhesive layer, and the resin of the insulating adhesive layer remains on the bottom of the hole. The method for manufacturing an interlayer connection member according to claim 3, wherein a hole is formed.   An insulating adhesive layer made of an insulating resin is laminated on the electrode of the conductor pattern layer of one wiring board on which a plurality of conductor pattern layers are formed, and a hole formed at a predetermined position of the insulating adhesive layer A multilayer printed wiring board characterized in that a metal sphere is disposed, an electrode with which the metal sphere contacts is formed in an annular shape, and a part of the ring is cut to form a slit. A step of laminating an insulating adhesive layer made of an insulating resin on the conductor pattern layer of one wiring board on which a plurality of conductor pattern layers are formed; and a step of forming a hole at a predetermined position of the insulating adhesive layer; A step of disposing a metal sphere in the hole, and the electrode of the other wiring board provided with an electrode in contact with the metal sphere is made to face the metal sphere so that the other wiring board is placed on the insulating adhesive layer. A method for producing a multilayer printed wiring board, comprising: laminating and fixing.

Images