JP2006049457A - Wiring board with built-in parts and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure reliability at higher levels in a wiring board with built-in parts and to provide its manufacturing method. <P>SOLUTION: The wiring board with built-in parts comprises: conductive embedded layers formed in a board thickness direction without revealing in the upper and lower sides of the board; electric/electronic parts with terminals embedded in the board so that the terminals might counter the embedded conductive layer; a connection material for connecting the terminals and conductive layers electrically and mechanically having an upper and lower directional size incorporated in an upper and lower directional dimension of the conductive layer, in the gap provided between the terminals of embedded electric/electronic parts and the conductive layers; and two upper and lower insulating layers provided so that they might cover the surface except the part connected to the connection material among the surfaces outside the embedded electric/electronic parts and might stick to the board thickness direction of the upper and lower sides of electric/electronic parts. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a component built-in wiring board and a manufacturing method thereof, and more particularly, to a component built-in wiring board suitable for ensuring higher reliability and a manufacturing method thereof.

An example of the component built-in wiring board is disclosed in Patent Document 1 below, for example. In this disclosure, the built-in component is connected to a land provided corresponding to each terminal of the component, as in the case of being mounted on the substrate. The component built in the wiring board preferably has a structure in which its periphery is completely covered with an insulating resin and closely adhered. In this respect, in the following document, there is a very narrow gap between the component and the board on which the component is mounted, and it is very difficult to fill the gap with resin. Depending on the application, such a gap tends to cause delamination due to poor insulation or expansion of the air in the gap due to heat during solder reflow, and there is a concern about reliability.
Japanese Utility Model Publication No. 5-53269

  The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a component built-in wiring board capable of ensuring a higher level of reliability and a method for manufacturing the same in a component built-in wiring board and a method for manufacturing the same. And

  In order to solve the above problems, a component built-in wiring board according to the present invention has a conductive layer formed in the thickness direction of the board and embedded without being exposed on the upper and lower surfaces of the board, and a terminal. An electrical / electronic component embedded in a plate so that the terminal faces the conductive layer, and a gap between the terminal of the embedded electrical / electronic component and the conductive layer, and the vertical direction of the conductive layer A connecting member having a vertical position and size contained in the dimensions, and electrically and mechanically connecting the terminal and the conductive layer; and an outer surface of the embedded electric / electronic component Of these, the upper and lower insulating layers are provided so as to cover portions other than the portion connected to the connecting member and to be in close contact with the electric / electronic component in the plate thickness direction.

  That is, in this component built-in wiring board, the connection (mounting) of the built-in component to the wiring board is connected to the conductive layer that is formed in the thickness direction of the board and is not exposed on the upper and lower surfaces of the board. This is done via a member. That is, this conductive layer is a longitudinal conductive layer. The parts to be incorporated are covered and adhered to the upper and lower insulating layers except for the part connected to the connecting member on the outer surface. Therefore, there is no gap around the part. Furthermore, the vertical position and size of the connecting member are included in the vertical size of the embedded conductive layer. Thereby, the conductor piece of a connection member does not enter into the above-mentioned two upper and lower insulating layers in the vertical direction, and the insulating function as the insulating layer can be kept sound. Therefore, the occurrence of short-circuit failure in the direction penetrating the upper and lower two insulating layers is greatly improved. Therefore, a higher level of reliability can be ensured.

  In addition, the method of manufacturing a component built-in wiring board according to the present invention has a wiring pattern on at least the upper and lower surfaces, an opening as a space for an electric / electronic component to be embedded, and an inner wall of the opening. A first step of manufacturing a core wiring board in which a conductive layer in the thickness direction of the plate is formed for connection to the electric / electronic component, and the electric / electronics to be built in the space of the core wiring board Position the component and place two flat plates to contact the upper and lower surfaces of the core wiring board, and connect the terminal of the electrical / electronic component and the conductive layer in the plate thickness direction with a conductive member An insulating layer is formed so as to overlap the upper and lower surfaces of the core wiring board to which the electrical / electronic component is connected by the conductive member and to fill the periphery of the electrical / electronic component. A third step. The features. This manufacturing method is one example of manufacturing the component built-in wiring board.

  In addition, another method of manufacturing a component built-in wiring board according to the present invention includes a wiring pattern on at least upper and lower surfaces, an opening as a space for electric / electronic components to be embedded, and an inner wall of the opening. A first step of manufacturing a core wiring board in which a conductive layer in the thickness direction of the board is formed for connection to the electric / electronic component at a part thereof, and a support having a first surface and a second surface A second step of disposing the electrical / electronic component on the first surface of the substrate; and the electrical / electronic component on the first surface of the support substrate on which the electrical / electronic component is disposed. A third step of stacking and arranging the core wiring boards such that the core wiring board is positioned at the opening of the core wiring board, and the second surface of the supporting base material and the supporting base material of the core wiring board are positioned. The two electric plates are arranged in contact with the surface opposite to the side to be A fourth step of connecting the terminal of the product and the conductive layer in the plate thickness direction with a conductive member, and overlapping the upper and lower surfaces of the core wiring board to which the electrical / electronic component is connected by the conductive member, and And a fifth step of forming an insulating layer so as to fill around the electric / electronic component. This manufacturing method is another example of manufacturing the above-described component built-in wiring board.

  According to the present invention, a higher level of reliability can be ensured in the component built-in wiring board and the manufacturing method thereof.

  As an embodiment of the present invention, the connection member may be solder. The connecting member may be a conductive adhesive. Both are suitable as connection members for electrical and mechanical connection.

  Further, as an embodiment, four wiring layers provided near the upper and lower surfaces of each of the upper and lower two insulating layers, and the surfaces of the conductor patterns formed by the wiring layers penetrating the upper and lower two insulating layers, respectively. And a first interlayer connection body sandwiched between the first and second interlayer connection bodies. Such an interlayer connection body can be arranged so as to be hidden under the conductor pattern by the wiring layer (board side), and the mounting space for the surface-mounted component is increased, and the component arrangement efficiency is improved.

  Here, each of the first and second interlayer connection bodies is made of a conductive composition and has a shape that has an axis that coincides with the layer direction and the diameter changes in the direction of the axis. It can be. Further, each of the first and second interlayer connection bodies is made of a conductive composition, and has a shape that has an axis that coincides with the layer direction and the diameter does not change in the direction of the axis. You can also The former is, for example, a case where an interlayer connection is formed by screen printing of a conductive composition and this is penetrated into an insulating layer to form an interlayer connection, and the latter is, for example, a via hole formed through the insulating layer. This is a case where an electrically conductive composition is filled into an interlayer connection body.

  Furthermore, each of the first and second interlayer connectors may be made of metal and have a shape that has an axis that coincides with the layer direction and has a diameter that changes in the direction of the axis. it can. Still further, each of the first and second interlayer connection bodies is made of metal and has a shape that has an axis that coincides with the layer direction and has a diameter that does not change in the direction of the axis. You can also. The former is, for example, a case where a metal plate is etched to form a bump (so-called etching bump) and this is inserted into an insulating layer to form an interlayer connection body. The latter is, for example, a bump formed by plating on a metal foil. This is a case where (so-called plating bumps) are formed and inserted into an insulating layer to form an interlayer connection body.

  As an embodiment of the manufacturing method, the second step may include a step of arranging the electric / electronic component in advance on one surface of the two flat plates. It is relatively easy to arrange the electric / electronic components on the flat plate side instead of the core wiring board because of its flatness.

  As another embodiment of the manufacturing method, the support base material can be made of the same type of insulating material as the core wiring board. Furthermore, the support substrate may have a metal plate portion and a surface that is peelable from the conductive member. The former uses an insulating material of the same type as the core wiring board because it has peelability from the conductive member. The latter uses a surface metal plate having peelability from the conductive member.

  Based on the above, embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view (FIG. 1A) and a partial plan view (FIG. 1B) schematically showing the structure of a component built-in wiring board according to an embodiment of the present invention.

  As shown in FIG. 1A, this embodiment is a six-layer wiring board having insulating layers 11 to 15 and having wiring layers 21 to 26 in the vicinity of the boundary and on the upper and lower surfaces, respectively. Electrical connections (interlayer connections) between adjacent wiring layers are made by conductive bumps 41 to 45, and these conductive bumps 41 to 45 can be arranged in a superimposed manner. Such conductive bumps 41 to 45 improve the utilization efficiency of the main surface of the wiring board and are suitable for high-density mounting. Reference numerals 31 and 32 on the upper and lower surfaces are solder resists.

  In addition, an electric / electronic component 33 (for example, a chip resistor here) is incorporated so as to be included in the horizontal level of the inner wiring layers 22, 23, 24, 25. Both terminals of the component 33 face the conductive layers 34 and 35 formed in the plate thickness direction and are electrically and mechanically connected via solders 36 and 37 as connecting members. As shown in the drawing, the conductive layers 34 and 35 have a longitudinal extension from the inner wiring layer 22 to the wiring layer 25 and are directly connected to the inner wiring layers 22, 23, 24, and 25. Is possible. The solders 36 and 37 are included in the vertical dimension of the conductive layers 34 and 35 in the vertical position and size.

  The component 33 is arranged as shown in FIG. That is, a through space is formed in the inner insulating layers 12, 13, 14 in order to incorporate the component 33, and this through space is formed by the solder 36, 37 for connecting the component 33 and the insulating layers 11, 15 on both the upper and lower sides. It is occupied by the protruding part to the inside. The component 33 is usually smaller in the thickness shown in FIG. 1 (a) than the width shown in FIG. 1 (b). However, since the thickness direction of the wiring board is shown in FIG. For 33, the thickness is displayed larger.

  Specifically, when a chip resistor of 0603 is used as the component 33, these insulating layers 12, 13 are set so that the total thickness of the insulating layers 12, 13, 14 is, for example, about 0.2 mm to 0.3 mm. 14 each have a thickness of about 0.06 mm to 0.1 mm.

  The material of each part is, for example, epoxy resin, polyimide resin, bismaleimide triazine resin, etc. for the insulating layers 11-15, copper, etc. for the wiring layers 21-26 and the conductive layers 34, 35, and the conductive bumps 41-45, For example, a conductive composition in which fine metal particles (silver, copper, gold, solder, etc.) are dispersed in a resin can be used. For the solders 36 and 37, a conductive adhesive can be used instead.

  The wiring board having the structure of this embodiment is extremely preferable for improving the reliability because the insulating layers 11 and 15 are in close contact with each other so as to cover the built-in component 33 and prevent the generation of voids. In addition, since the placement positions of the solders 36 and 37 are included in the longitudinal dimensions of the conductive layers 34 and 35 in the vertical direction, it is ensured that the vertical insulating function that the insulating layers 11 and 15 should be impaired may be impaired. Is excluded. Thereby, the reliability as a wiring board is improved.

  In the above description, the chip resistor has been described as an example of the electric / electronic component 33, but the same application is possible when the terminal arrangement structure such as a chip capacitor, a chip inductor, and a chip diode is substantially the same as the chip resistor. Even in the case of chip-type discrete transistors and semiconductor devices housed in packages, for example, if the lead pins are projected horizontally from the middle of the thickness direction of the mold resin that is the package, the number of the lead pins in the board thickness direction It is possible to cope with this by separately forming the conductive layer. In the case of a bare semiconductor chip, by forming a protruding electrode on a pad as close as possible to the periphery, this protruding electrode can be used for electrical and mechanical connection with a conductive layer on the wiring board side. .

  To manufacture the component built-in wiring board shown in FIG. As a first stage, a core wiring board (wiring board material including a layer in which components are to be incorporated) of the wiring boards is manufactured. First, a copper foil (thickness is, for example, 18 μm) at the previous stage of the wiring layer 22 is prepared. A substantially conical conductive bump of about 2 mm (the previous stage of the conductive bump 42) is formed. This can be done, for example, by printing a conductive paste on the copper foil using screen printing.

  As the conductive paste, for example, a paste in which metal particles (silver, gold, copper, solder, etc.) are dispersed in a paste-like resin such as an epoxy resin, and a volatile solvent is mixed can be used. After printing, the conductive paste is cured by drying in an oven, for example.

  Next, using a dedicated machine, the front bump of the conductive bump 42 is made to face the FR-4 prepreg (thickness is, for example, 60 μm) to be the insulating layer 12 on the copper foil. To penetrate. The FR-4 prepreg is obtained by, for example, impregnating a reinforcing material such as glass fiber with a curable resin such as an epoxy resin. Moreover, it is in a semi-cured state before being cured, and has fluidity and heat curability due to heat. A wiring board material having the same configuration as this stage is referred to as an A material for convenience.

  Next, a copper foil (thickness is, for example, 18 μm) at the previous stage of the wiring layer 23 is laminated and integrated on the prepreg, and the prepreg is cured at the same time. For this purpose, a vacuum laminating hot press is used to set it to a predetermined temperature and pressure profile. By lamination and integration, the conductive bumps 42 are sandwiched between the copper foils in a shape as shown in FIG.

  Next, the wiring layer 23 is formed by circuit patterning of the copper foil on one side. For this purpose, for example, first, the surface of the copper foil is chemically polished to improve the adhesion with the resist dry film, and then the resist dry film is laminated on the copper foil. Then, the dry film is exposed with an alignment exposure machine having, for example, an ultrahigh pressure mercury lamp through a photomask, and further spray-developed with sodium carbonate. By leaving the dry film of this development pattern on the copper foil, a patterned resist is formed on the copper foil.

  When the resist is formed on the copper foil, the copper foil located at the position where the resist has been removed (position removed as a resist pattern) is spray-etched using a chemical solution based on ferric chloride as an etchant using the resist as a mask. Thereby, the wiring layer 23 is formed from copper foil. The formed wiring layer 23 is subjected to a blackening reduction process in order to improve adhesion with an insulating layer to be laminated thereafter. A wiring board material having the same configuration as this stage is referred to as a B material for convenience.

  Next, a substantially conical conductive bump (the previous stage of the conductive bump 43) is formed at a necessary position on the patterned wiring layer 23 (a position according to a specific wiring board layout). The formation of the conductive bump 43 can be performed in the same manner as in the bump formation in the previous stage of the conductive bump 42. The conductive paste formed by screen printing is dried and cured in an oven. It should be noted that the previous bump of the conductive bump 43 can be positioned so as to overlap the conductive bump 42 and the wiring layer 23.

  Next, using a dedicated machine, the prepreg (thickness is nominally 60 μm, for example) to be the insulating layer 13 is made to face the insulating layer 12, and the bump in the previous stage of the conductive bump 43 is made into this semi-cured prepreg. To penetrate. As this prepreg, the same prepreg as in the case of the insulating layer 12 can be used. A wiring board material having the same configuration as this stage is called a C material for convenience.

  Next, the prepreg side to be the insulating layer 13 of the C material and the side having the patterned copper foil of the B material are opposed and laminated, and the prepreg to be the insulating layer 13 is cured. Here, the B material corresponds to the insulating layer 14, the copper foil to be the wiring layer 25, the conductive bumps 44, and the wiring layer 24 in FIG. 1.

  For the lamination / integration, for example, alignment is performed by a lay-up device, the C material and the B material are arranged in an overlapping manner, and this is set to a predetermined temperature and pressure profile using a vacuum lamination heat press. By this lamination and integration, the conductive bumps 43 are sandwiched between the wiring layers 23 and 24 in the shape shown in FIG. Also, the wiring layer 24 sinks to the insulating layer 13 side due to the fluidity of the prepreg to be the insulating layer 13 due to heat.

  As described above, a core wiring board having both sides made of copper foil is formed. In this embodiment, the core wiring board having four wiring layers (or copper foils) is formed as described above, but the number of wiring layers is not limited to four. For example, an even number of wiring layers such as 2, 6, 8,... Or an odd number of wiring layers such as 3, 5, 7,. In the case of the number of these wiring layers, it can be formed by applying the above-described process. Further, in this embodiment, the interlayer connection of the core wiring board is made by the conductive bumps 42, 43, 44. However, the present invention is not limited to this, but the high-density mounting property is inferior as the wiring board, but for example, a well-known through hole It may be due to.

  Continuing the description of the process, after the core wiring board of double-sided copper foil is formed, next, a through hole for the component 33 is formed at a required position of the core wiring board. The through-hole is used to form a conductive layer in the plate thickness direction used for connection with the built-in component, and is a part of a space where the built-in component is located.

  Next, for example, a copper plating layer is formed with a thickness of, for example, 20 μm so as to include the inner wall surface of the through hole. For the formation of the plating layer, for example, a continuous surface seed layer is first formed by electroless plating such as chemical copper plating, and then electroplating is performed using, for example, a copper sulfate plating bath using the formed seed layer as a seed. It can be done by processing. A plating layer can be efficiently formed by such two-stage plating. In addition, the plating layer formed in the through hole can be electrically connected to the wiring layers 23 and 24 in the middle of the core wiring board.

  Next, patterning is performed on the copper foils on both sides and the plating layers located on both sides to form the wiring layers 22 and 25. This patterning can be performed in the same manner as the step of forming the wiring layer 23, respectively. That is, the procedures are chemical polishing, resist dry film lamination, exposure through a photomask, development, and etching. The formed wiring layers 22 and 25 include land portions (having a diameter of, for example, 0.8 mm) with respect to the plating layer formed on the inner wall surface of the through hole.

  Next, the core wiring board is processed so as to divide the plated layer on the inner wall surface of the through hole and to independently form the conductive layers 34 and 35 which are connection portions with the built-in components. The processing method here depends on drilling using an NC drill. For example, two plating layer dividing through holes having a diameter of 0.8 mm are formed almost adjacent to each other at a position on the core wiring board perpendicular to the direction in which the through holes are arranged. According to the division of the plating layer by such a drill, the conductive layers 34 and 35 can be easily divided and formed using an existing apparatus.

  As described above, it is possible to obtain a core wiring board in which a space for incorporating a component (a space by a through hole and a plating layer dividing through hole) is formed. It should be noted that the plating layer can be divided without using drilling. For example, there are a method of punching with a mold and a method using a cutting machine.

  Next, the process of mounting the component 33 on the core wiring board will be described with reference to FIG. FIG. 2 is a process diagram schematically showing an example of a manufacturing process of the component built-in wiring board shown in FIG. 1. In particular, the positions and sizes of the solders 36 and 37 in the vertical direction are the conductive layers 34 and 35. It is a figure which shows the example of a process for ensuring that it is included in the vertical direction dimension.

  First, as shown in FIG. 2 (a), a flat plate 51 is prepared, and cream solder 36A, 37A (for example, a fine powder of an alloy made of tin, silver, or copper in the flux is formed by screen printing at a predetermined position on the flat plate 51, for example. Print the dispersed one). The flat plate 51 is made of, for example, aluminum having a thickness of 1 mm, and the surface thereof is coated with a fluororesin film having a peelability from the molten solder. Next, as shown in FIG. 2B, the 0603 size component 33 is placed at a predetermined position on the flat plate 51 using, for example, a mounter (that is, both terminals of the component 33 are located near the cream solders 36A and 37A). Like).

  Next, as shown in FIG. 2C, the above-described core wiring board is placed at a predetermined position of the flat plate 51 using, for example, a mounter (that is, here, the component 33 is located in the space for incorporating the components of the core wiring board). To place). Next, as shown in FIG. 2D, another flat plate 52 is brought into contact with the upper side of the core wiring board and laminated. The flat plate 52 may have the same configuration as the flat plate 51. And in this state, it applies to a reflow furnace and performs reflow with a peak temperature of 250 degreeC.

  Thus, the cream solders 36A and 37A are melted to become solders 36 and 37 as connecting members (conductive members) located between the terminals of the component 33 and the conductive layers 36 and 37. In this reflow process, the terminals of the component 33 and the conductive layers 36 and 37 exhibit wettability with respect to the melted solder, and exhibit releasability with respect to the flat plates 51 and 52. The vertical position and size of the conductive layers 34 and 35 are included in the vertical dimension. By removing the upper and lower flat plates 51 and 52 from the core wiring board after reflow, a core wiring board with components mounted as shown in FIG. 2E can be obtained.

  As a modification, a glass epoxy plate equivalent to FR-4 can be used as the flat plates 51 and 52 in place of the fluororesin-coated aluminum plate. Also in this case, releasability is exhibited with respect to the molten solder. Moreover, you may apply oven heating besides applying to a reflow furnace. Further, instead of using the cream solders 36A and 37A, a conductive adhesive may be printed on the flat plate 51 by, for example, screen printing. The component-mounted core wiring board obtained as described above is subjected to blackening reduction treatment in order to improve the adhesion between the wiring layers 22 and 25 on both sides thereof and the insulating layer to be laminated thereafter.

  Next, a portion including the upper and lower insulating layers 11 and 15 is laminated on the core wiring board on which the component 33 is mounted. For this purpose, the prepreg side of the A material described above is opposed to each other on both sides of the component-mounted core wiring board, and these are integrated. At this time, the prepregs to be the insulating layers 11 and 15 are cured. Here, the A material is the insulating layer 11, the copper foil to be the wiring layer 21, the conductive bump 41 portion, and the insulating layer 15, the copper foil to be the wiring layer 26, the conductive bump 45 portion in FIG. 1. Respectively.

  For this lamination / integration, for example, alignment is performed with a lay-up device, the core wiring board and the A material are arranged in an overlapping manner, and this is set to a predetermined temperature and pressure profile using a vacuum lamination heat press. By this lamination and integration, the conductive bumps 41 and 45 are sandwiched between copper foils or wiring layers in a shape as shown in FIG.

  Further, the wiring layer 22 is positioned by sinking to the insulating layer 11 side due to the fluidity of the prepreg to be the insulating layer 11, and the wiring layer 25 is insulated by the fluidity of the prepreg to be the insulating layer 15. It sinks to the layer 15 side and comes to be positioned. Further, due to the fluidity of the prepreg that should become the insulating layers 11 and 15, the insulating layer is integrally formed with the insulating layers 11 and 15 in the periphery so as to cover and closely adhere to the built-in component 33. This eliminates the need for a hole filling process around the part 33, which simplifies the process and prevents the generation of voids, thereby improving the reliability.

  Instead of this, the A material laminated on the outside may have a larger number of wiring layers. Further, the A material laminated on the outside does not necessarily need to be accompanied by the conductive bump 41 (or 45) as shown in FIG. In this case, since there is no conductive bump 41, the interlayer connection between the copper foil to be the wiring layer 21 (26) and the wiring layer 22 (25) cannot be made by the conductive bump. Through-holes can be provided in these layers, and these interlayer connections can be made through these through-holes.

  After the insulating layers 11 and 15 to be located outside are laminated and integrated with the core wiring board, the copper layers on both outsides are patterned to form wiring layers 21 and 26. This patterning can be performed in the same manner as the wiring layer 23 forming step described above. That is, the procedures are chemical polishing, resist dry film lamination, exposure through a photomask, development, and etching. In addition, after the formation of the outer insulating layers 11 and 15 described above, an insulating layer may be further laminated and integrated (build-up) in the same manner on the outer side.

  Next, solder resists 31 and 32 are formed at predetermined positions on the outermost surface. Further, a nickel / gold (nickel base) layer (not shown) is formed by electroless plating at a portion of the wiring layer 21 or 26 where the solder resist is not formed to prevent corrosion. And a wiring board is cut out so that it may become a predetermined | prescribed external shape with a router processing machine. Thus, the component built-in wiring board according to the present embodiment can be obtained.

  Next, a component built-in wiring board according to another embodiment of the present invention will be described with reference to FIG. FIG. 3 is a schematic cross-sectional view showing the structure of a component built-in wiring board according to another embodiment of the present invention. Components identical or equivalent to those shown in FIG. It is. The description is omitted unless it is added.

  This component built-in wiring board is different in that instead of the conductive bumps 41 to 45, interlayer connection members 61 to 65 filled with a conductive composition are used. Such a wiring board can be manufactured as follows, for example. First, for example, resin sheets to be used as the insulating layers 12 and 14 are prepared, via holes (through holes) are formed at predetermined positions by, for example, laser processing, and the conductive composition is filled in the via holes, and the interlayer connector 62 is formed. , 64 are formed respectively. And copper foil is arrange | positioned facing each of both surfaces of this insulating layer, and it integrates with a lamination press. After the integration, the copper foil on one side is patterned and processed into the wiring layers 23 and 24 to obtain two double-sided wiring boards patterned only on one side.

  Next, a resin sheet to be used as the insulating film 13 is separately prepared, and via holes are formed at predetermined positions, and then the conductive composition is similarly filled to form an interlayer connection 63. Further, the patterned copper foil side (wiring layer 23 or 24 side) of the double-sided wiring board is disposed opposite to both surfaces of the resin sheet to be the insulating layer 13 and integrated by a laminating press. At this stage, the core wiring board is in a state before a through hole for incorporating the component 33 is formed. In the following, by applying a process such as drilling for incorporating the component 33 as already described, a component-mounted core wiring board can be obtained.

  Next, when the components are mounted, the portions including the upper and lower insulating layers 11 and 15 are stacked. For this purpose, a resin sheet to be used as the insulating layer 11 (15) is prepared, a via hole is formed at a predetermined position thereof, and similarly, the conductive composition is filled to form the interlayer connector 61 (65). Further, a core wiring board or a copper foil with components mounted on each side of the resin sheet to be the insulating layer 11 (15) is disposed opposite to each other and integrated by a laminating press. In the following, the steps as already described, such as patterning of the copper foils on both outer sides, are performed. Thus, the configuration shown in FIG. 3 is obtained.

  The interlayer connectors 61 to 65 of this embodiment have a cylindrical shape whose axis direction coincides with the stacking direction (that is, a shape whose diameter does not change in the axis direction). In this embodiment, the process of drilling holes in the insulating layers 11 to 15 cannot be said to be efficient, but the shape of the solders 36 and 37 that are members for connecting the built-in components 33 is insulated as in the previous embodiment. It does not impair the longitudinal insulation function that the layer 11 or 15 should have.

  Next, a component built-in wiring board according to still another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic cross-sectional view showing the structure of a component built-in wiring board according to still another embodiment of the present invention. The same or equivalent components as those shown in FIG. 1 or FIG. The same reference numerals are given. The description is omitted unless it is added.

  This component built-in wiring board is different in that instead of the conductive bumps 61, 62, 64, 65, metal interlayer connectors 71, 72, 74, 75 (conductive bumps) formed by plating are used. . The interlayer connection 63 is the same as that of the embodiment of FIG. Such a wiring board can be manufactured as follows, for example. That is, instead of forming each conductive bump by screen printing in the embodiment shown in FIG. 1, a patterned resist for plating is formed on a copper foil, and plating is performed on a portion where the resist is removed. Form bumps by growth. By treating the bumps thus formed as a substitute for the conductive bumps in the embodiment shown in FIG. 1, it is possible to obtain a component built-in wiring board configured as shown in FIG. .

  The interlayer connectors 61, 62, 64, 65 follow a resist pattern shape for plating and have a columnar or frustum shape whose axis direction coincides with the stacking direction (that is, the diameter changes in the axis direction). Or a shape that has not changed). Although this embodiment is slightly inferior in production efficiency in that a step of making a hole in the insulating layer 13 remains, the shape of the solders 36 and 37 that are members for connecting the built-in component 33 is the same as in the previous embodiment. This does not impair the longitudinal insulating function that the insulating layer 11 or 15 should have.

  Next, a component built-in wiring board according to still another embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic cross-sectional view showing the structure of a component built-in wiring board according to still another embodiment of the present invention. Components identical or equivalent to those shown in FIG. It is attached. The description is omitted unless it is added.

  This embodiment is different in that instead of the conductive bumps 41 to 45, interlayer connectors 81 to 85 (conductive bumps) by metal plate etching are used. Such a wiring board can be manufactured as follows, for example. That is, instead of forming each conductive bump by screen printing in the embodiment shown in FIG. 1, a metal plate (copper plate) having a certain thickness is prepared, and the bump formation portion is removed on the surface of this metal plate. Etch to form bumps. By treating the bumps formed in this way as a substitute for the conductive bumps in the embodiment shown in FIG. 1, a component built-in wiring board having the configuration shown in FIG. 5 can be obtained in substantially the same process. .

  The interlayer connectors 81 to 85 have a cone shape or a frustum shape whose axis direction coincides with the stacking direction (that is, a shape whose diameter changes in the axis direction) depending on the degree of side etching to the metal plate in bump formation. )become. In this embodiment, bump formation is not as efficient as screen printing, but the shape of the solders 36 and 37 which are members for connecting the built-in component 33 is the same as that of the previous embodiment in that the insulating layer 11 or 15 is formed. It does not impair the vertical insulation function that should be present.

  Next, steps that can be employed instead of the steps shown in FIG. 2 will be described with reference to FIG. FIG. 6 is a process diagram schematically showing another example of the manufacturing process of the component built-in wiring board shown in FIG. 1, and in particular, the positions and sizes of the solders 36 and 37 in the vertical direction are the conductive layer 34. , 35 is a diagram showing an example of a process for ensuring inclusion in the vertical dimension of 35. In FIG. 6, the same or equivalent parts as those already described are denoted by the same reference numerals.

  First, the flat plate 51 is prepared as a support base material. The flat plate 51 may have the same configuration as that in FIG. 6 (a), 6 (b), 6 (c) and the case shown in FIG. Next, as shown in FIG. 6D, the heater built-in flat plates 92 and 93 are arranged on the upper side of the core wiring board and the lower side of the flat plate 51 so as to be in contact therewith, respectively. In this state, the heating function of the heater built-in flat plates 92 and 93 is operated to heat at a peak temperature of 250 ° C.

  Thus, the cream solders 36A and 37A are melted to become solders 36 and 37 as connecting members (conductive members) located between the terminals of the component 33 and the conductive layers 36 and 37. In this heating process, what exhibits wettability to the molten solder is the terminal of the component 33 and the conductive layers 36 and 37, and exhibits peelability to the flat plate 51. The position and size in the direction are included in the longitudinal dimension of the conductive layers 34 and 35. By removing the upper and lower heater built-in flat plates 92 and 93 and the flat plate 51 from the core wiring board after heating, a core wiring board with components mounted as shown in FIG. 6E can be obtained.

  Also in this embodiment, as a modification, a glass epoxy plate equivalent to FR-4 can be used as the flat plate 51 in place of the fluororesin-coated aluminum plate. Furthermore, as shown in FIG. 2, the flat plates 51 and 52 may be disposed above and below the core wiring board, and the heater built-in flat plates 92 and 93 may be disposed outside the core wiring boards and heated.

1 is a cross-sectional view and a partial plan view schematically showing the structure of a component built-in wiring board according to an embodiment of the present invention. Process drawing which shows an example of the manufacture process of the component built-in wiring board shown in FIG. 1 with a typical cross section. Sectional drawing which shows typically the structure of the wiring board with a built-in component which concerns on another embodiment of this invention. Sectional drawing which shows typically the structure of the component built-in wiring board which concerns on another embodiment of this invention. Sectional drawing which shows typically the structure of the component built-in wiring board which concerns on another embodiment of this invention. Process drawing which shows a typical cross section in another example of the manufacturing process of the component built-in wiring board shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11, 12, 13, 14, 15 ... Insulating layer 21, 22, 23, 24, 25, 26 ... Wiring layer, 31, 32 ... Solder resist, 33 ... Electric / electronic component, 34, 35 ... Conductive layer, 36 , 37 ... solder (connection member, conductive member), 36A, 37A ... cream solder, 41, 42, 43, 44, 45 ... conductive bump (interlayer connection body), 51, 52 ... flat plate, 61, 62, 63, 64, 65 ... interlayer connection by filling with conductive composition, 71, 72, 74, 75 ... interlayer connection formed by plating, 81, 82, 83, 84, 85 ... interlayer connection formed by metal plate etching Body, 92, 93 ... Flat plate with built-in heater.

Claims (13)

A conductive layer formed in the thickness direction of the plate and embedded in the upper and lower surfaces of the plate without being exposed; and
An electrical / electronic component having a terminal and embedded in a plate so that the terminal faces the embedded conductive layer;
Provided in the gap between the terminal of the embedded electrical / electronic component and the conductive layer, has a vertical position and size contained in the vertical dimension of the conductive layer, and the terminal and the A connection member for electrically and mechanically connecting the conductive layer;
Two upper and lower insulating layers provided so as to cover a portion of the outer surface of the embedded electric / electronic component other than the portion connected to the connecting member and to be in close contact with the electric / electronic component in the plate thickness direction. A component built-in wiring board comprising:   The component built-in wiring board according to claim 1, wherein the connecting member is solder.   The component built-in wiring board according to claim 1, wherein the connection member is a conductive adhesive. Four wiring layers provided near the upper and lower surfaces of each of the two upper and lower insulating layers;
And further comprising first and second interlayer connectors that pass through each of the two upper and lower insulating layers and are respectively sandwiched between the surfaces of the conductor pattern formed by the wiring layer. Item 1. The component built-in wiring board according to Item 1.   The first and second interlayer connectors are each made of a conductive composition and have a shape that has an axis that coincides with the layer direction and has a diameter that changes in the direction of the axis. The component built-in wiring board according to claim 4.   Each of the first and second interlayer connectors is made of a conductive composition and has a shape that has an axis that coincides with the layer direction and has a diameter that does not change in the direction of the axis. The component built-in wiring board according to claim 4.   The first and second interlayer connectors are each made of metal and have a shape that has an axis that coincides with the layer direction and has a diameter that changes in the direction of the axis. 4. The component built-in wiring board according to 4.   The first and second interlayer connectors are each made of metal and have a shape that has an axis that coincides with the layer direction and has a diameter that does not change in the direction of the axis. 4. The component built-in wiring board according to 4. At least a wiring pattern on both upper and lower surfaces and an opening as a space for an electric / electronic component to be incorporated, and a thickness direction for connecting the electric / electronic component to a part of the inner wall of the opening A first step of manufacturing the core wiring board on which the conductive layer is formed;
The electric / electronic component to be incorporated is positioned in the space of the core wiring board, and two flat plates are arranged so as to be in contact with the upper and lower surfaces of the core wiring board, respectively. A second step of connecting the terminal and the conductive layer in the plate thickness direction with a conductive member;
A third step of laminating and forming an insulating layer so as to overlap each of the upper and lower surfaces of the core wiring board to which the electric / electronic component is connected by the conductive member and to fill the periphery of the electric / electronic component. A method for manufacturing a component built-in wiring board.   10. The method of manufacturing a component built-in wiring board according to claim 9, wherein the second step includes a step of arranging the electrical / electronic component in advance on one surface of the two flat plates. At least a wiring pattern on both upper and lower surfaces and an opening as a space for an electric / electronic component to be incorporated, and a thickness direction for connecting the electric / electronic component to a part of the inner wall of the opening A first step of manufacturing the core wiring board on which the conductive layer is formed;
A second step of disposing the electrical / electronic component on the first surface of a support substrate having a first surface and a second surface;
Thirdly arranging the core wiring board on the first surface of the support substrate on which the electric / electronic component is arranged, so that the electric / electronic component is positioned at the opening of the core wiring board. And the process of
Two flat plates are disposed in contact with the second surface of the support substrate and the surface of the core wiring board opposite to the side where the support substrate is located, and the electric / electronic component A fourth step of connecting the terminal and the conductive layer in the plate thickness direction with a conductive member;
And a fifth step of stacking and forming an insulating layer so as to overlap the upper and lower surfaces of the core wiring board to which the electric / electronic component is connected by the conductive member and to fill the periphery of the electric / electronic component. A method for manufacturing a component built-in wiring board.   The method of manufacturing a component built-in wiring board according to claim 11, wherein the support base is made of an insulating material of the same type as the core wiring board.   The method of manufacturing a component built-in wiring board according to claim 11, wherein the support base member has a metal plate portion and a surface that is peelable from the conductive member.

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