JP2010272563A - Wiring board with built-in component and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring board with a built-in component, which improves dissipation property in the built-in component without increasing a cost, and also to provide a method of manufacturing the same. <P>SOLUTION: The wiring board with the built-in component includes: a first insulating layer; a second insulating layer located by lamination with respect to the first insulating layer; an electronic component which is embedded in the second insulating layer and has a semiconductor chip having a first surface with a terminal and a second surface located oppositely to the first surface; a thermal conductor which is further embedded in the second insulating layer and has a first surface located oppositely to and spaced apart from the second surface of the semiconductor chip and a second surface located oppositely to and spaced apart from the edge of the semiconductor chip; an adhesive member arranged by filling between the electronic component and the thermal conductor; a wiring pattern held between the first insulating layer and the second insulating layer and including a connection land for the electronic component; and a conductive member which is held between the electronic component and the connection land of the wiring pattern, so as to electrically and mechanically connect the electronic component to the connection land. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a component built-in wiring board in which components are embedded and mounted in an insulating plate and a method for manufacturing the same, and more particularly to a component built-in wiring board in which electronic components having semiconductor chips are embedded and mounted and a method for manufacturing the same.

  An example of a component built-in wiring board in which a semiconductor chip is embedded and mounted by flip connection is disclosed in Japanese Unexamined Patent Application Publication No. 2003-197849. If a semiconductor chip (bare chip) is flip-connected, the thickness generated by the mounting is saved to a minimum. Therefore, the flip connection is an effective method for incorporating an electronic component having a semiconductor chip in a wiring board.

  However, when the electronic component is not limited to the flip connection, and the electronic component is embedded in the wiring board, the electronic component is sealed with the insulating resin for the wiring board, and thus heat dissipation in the electronic component may be a problem. . The insulating resin for the wiring board is not particularly considered for thermal conductivity, and the heat radiation is considerably worse than in the air. An electronic component having a semiconductor chip significantly increases its heat generation depending on its rated voltage and integration degree.

  Therefore, the wiring board with built-in electronic components becomes hot, destroying the component mounting part, damaging the connection part of the wiring board, reducing reliability, and if excessive, smoke, ignition, etc. A condition can also be triggered. As a countermeasure, it can be considered that the insulating resin used for the wiring board is replaced with a resin having good thermal conductivity. However, since it is not a general material but a special material, it is disadvantageous in terms of availability and cost, and further, the workability is also different, resulting in an increase in manufacturing process costs.

JP 2003-197849 A

  The present invention relates to a component built-in wiring board in which an electronic component having a semiconductor chip is embedded and mounted, and a method of manufacturing the same, and a component built-in wiring board capable of improving the heat dissipation of a built-in component without incurring an increase in cost. It aims at providing the manufacturing method.

  In order to solve the above-described problem, a component built-in wiring board according to an aspect of the present invention includes a first insulating layer, a second insulating layer positioned in a stacked manner with respect to the first insulating layer, An electronic component having a semiconductor chip having a first surface having a terminal and a second surface opposite to the first surface, embedded in the second insulating layer; and the second insulating layer A heat conductor having a first surface facing and spaced from the second surface of the semiconductor chip, and a second surface facing and spaced from the end surface of the semiconductor chip; The connection land for the electronic component provided between the adhesive member provided between the electronic component and the thermal conductor, and the first insulating layer and the second insulating layer. And a wiring pattern including the electronic component and the connection land of the wiring pattern. , Characterized by comprising a conductive member for electrically and mechanically connecting the electronic component and the connection lands.

  That is, in this component built-in wiring board, the heat conductor is embedded via the adhesive member so as to be opposed to the back surface and the end surface of the semiconductor chip included in the embedded electronic component. Therefore, the heat generated by the electronic component is transferred to the heat conductor via the adhesive member, and a state in which heat is accumulated in the electronic component is avoided accordingly. That is, more efficient heat dissipation of the electronic component can be achieved. There is no need to use a special insulating material for the wiring board, and the cost is not increased.

  According to another aspect of the present invention, there is provided a method of manufacturing a component built-in wiring board, comprising: an electronic device having a semiconductor chip having a first surface having a terminal and a second surface opposite to the first surface. A heat conductor having a first step surface, a second step surface higher than the first step surface, and a rising surface connecting the first step surface and the second step surface to the component. Mounting and fixing via an adhesive member so that the first step surface faces the second surface of the semiconductor chip and the rising surface faces the end surface of the semiconductor chip; Patterning a first metal foil laminated on an insulating plate to form a first wiring pattern including lands for mounting the electronic component; applying cream solder on the lands; The electronic component is placed on the land via the cream solder. Placing the semiconductor chip with the first surface side facing down, reflowing the cream solder, and mounting the electronic component on the first insulating plate; Patterning a second metal foil different from the first metal foil laminated on a second insulating plate different from the insulating plate to form a second wiring pattern; and A step of laminating a third insulating plate different from the second insulating plate on the side of the second insulating plate on which the second wiring pattern is present, and a step different from the first to third insulating plates. The fourth, third, and second insulating plates are integrated in order of the stacking positions in the first insulating plate so that the electronic component and the heat conductor are embedded in the four insulating plates. And a process.

  This manufacturing method is an example of a process for manufacturing the component inner layer wiring board. In this method, the electronic component is, for example, an electronic component of a chip scale package that can be mounted by cream solder. According to this manufacturing method, even if a heat conductor for heat dissipation measures is introduced, the component built-in wiring board having the above structure can be obtained without sacrificing productivity.

  In addition, a method of manufacturing a component built-in wiring board according to still another aspect of the present invention includes a semiconductor chip that includes a first surface having terminals and a second surface opposite to the first surface. A heat conductor having a first step surface, a second step surface higher than the first step surface, and a rising surface connecting the first step surface and the second step surface on the electronic component Mounting and fixing via an adhesive member so that the first step surface faces the second surface of the semiconductor chip and the rising surface faces the end surface of the semiconductor chip; Forming a conductive bump on the terminal of the semiconductor chip of the component, patterning the first metal foil laminated on the first insulating plate, and including a land for flip mounting the electronic component A step of forming a first wiring pattern; and A step of flip-mounting the electronic component on the first insulating plate so that the bumps face each other, and the first metal laminated on a second insulating plate different from the first insulating plate Patterning a second metal foil different from the foil to form a second wiring pattern, and forming a third insulating plate different from the first and second insulating plates on the second insulating plate A step of laminating on a side having the second wiring pattern, and the electronic component and the heat conductor are embedded in a fourth insulating plate different from the first to third insulating plates. And a step of integrating the fourth, third, and second insulating plates in order of the stacking positions in a laminated manner on one insulating plate.

  This manufacturing method is another example of the process for manufacturing the component inner layer wiring board. In this method, the electronic component is an electronic component in which conductive bumps are formed on the terminals of a semiconductor chip. Even in this manufacturing method, even if a heat conductor for heat dissipation measures is introduced, the component built-in wiring board having the above structure can be obtained with almost no sacrifice in productivity.

  According to the present invention, in a component built-in wiring board in which an electronic component having a semiconductor chip is embedded and mounted, and a method for manufacturing the same, a component built-in wiring that can improve the heat dissipation of a built-in component without increasing costs. A board and a manufacturing method thereof can be provided.

The longitudinal cross-sectional view which shows typically the structure of the component built-in wiring board which concerns on one Embodiment of this invention. The cross-sectional view which shows typically the structure of the component built-in wiring board in the A-Aa position shown in FIG. Process drawing which shows a part of manufacturing process of the component built-in wiring board shown in FIG. Process drawing which shows another part of manufacturing process of the component built-in wiring board shown in FIG. FIG. 9 is a process diagram schematically showing still another part of the manufacturing process of the component built-in wiring board shown in FIG. 1. Process drawing which shows the modification of the manufacturing process shown in FIG. 3 in a typical cross section. The longitudinal cross-sectional view which shows typically the structure of the wiring board with a built-in component which concerns on another embodiment of this invention. The longitudinal cross-sectional view which shows typically the structure of one wiring board raw material for manufacturing the component built-in wiring board shown in FIG. The longitudinal cross-sectional view which shows typically the structure of the component built-in wiring board which concerns on another embodiment of this invention. The longitudinal cross-sectional view which shows typically the structure of one wiring board raw material for manufacturing the component built-in wiring board shown in FIG.

  As an embodiment of the present invention, the thermal conductor may have a surface facing the entire circumference of the end surface of the semiconductor chip as the first surface. According to this, the heat transfer from the electronic component to the heat conductor becomes efficient, which is preferable for further heat dissipation.

  As an embodiment, the electronic component can be flip-connected to the connection land of the wiring pattern via the conductive member. As a mounting mode of the electronic component on the connection land, even if the electronic component is accompanied by a heat conductor via an adhesive member, the flip connection can be performed in this way. According to this, the general advantage of flip connection can be enjoyed.

  Further, as an embodiment, the wiring pattern includes a fixing land for the heat conductor, and the heat conductor sandwiched between the heat conductor and the fixing land of the wiring pattern; A heat conducting member for thermally and mechanically connecting the fixing land may be further provided, and the electronic component may be an electronic component of a chip scale package. Thus, when the electronic component is an electronic component of a chip scale package, the mounting height of the electronic component via the conductive member is flexible, and the heat conductor is also connected to the wiring pattern via the heat conductive member. Is relatively easy. According to this configuration, the heat generated by the electronic component is further transferred to the heat conductor via the conductive member, the wiring pattern, and the heat conducting member, and accordingly, a state where heat is accumulated in the electronic component is avoided. That is, more efficient heat dissipation of the electronic component can be achieved.

  Here, the conductive member and the heat conducting member can be made of the same material. According to this, during the manufacturing process, the step of providing the conductive member and the step of providing the heat conducting member can be performed at the same time, which can contribute to an improvement in manufacturing efficiency.

  As an embodiment, the heat conductor may be copper as a material thereof. By using a copper conductor as the heat conductor, good heat conductivity can be obtained.

  Here, the thermal conductor may have a roughened surface. By roughening the surface, the adhesion with the insulating layer in which the heat conductor is embedded can be enhanced. Thereby, the reliability as a wiring board can be improved.

  Further, as an embodiment, the surface of the thermal conductor opposite to the first surface is a third surface, and is provided in the second insulating layer so as to be separated from the third surface. It can be further provided with a second wiring pattern and a heat conducting member sandwiched between the third surface of the heat conductor and the second wiring pattern. According to this, it is preferable that heat radiation further proceeds from the heat conductor through the heat conducting member.

  Here, a third wiring pattern provided in a layer on the second insulating layer in a layered manner with the second wiring pattern and a part of the second insulating layer in the stacking direction pass through the second wiring pattern. It is sandwiched between the surface of the wiring pattern and the surface of the third wiring pattern, is made of a conductive composition, has an axis that coincides with the lamination direction, and the diameter changes in the direction of the axis. And an interlayer connection body having a shape, wherein the interlayer connection body and the heat conducting member are conductive compositions made of the same material.

  In this aspect, the heat conducting member is formed simultaneously with the formation of the interlayer connector (= vertical wiring portion) to be sandwiched between the surface of the second wiring pattern and the surface of the third wiring pattern during the manufacturing process. Can be formed. Therefore, production with high production efficiency is possible.

  As an embodiment of the manufacturing method, the step of forming the first wiring pattern is a step of forming a second land for fixing the thermal conductor so as to be adjacent to the land, The step of applying the cream solder is a step of further applying a second cream solder on the second land, and the electronic component is placed on the land via the cream solder. The step of placing the first surface side downward is performed by using the electronic component to which the heat conductor is attached, and the second step surface of the heat conductor is the second step surface. The step of facing the second land through cream solder, reflowing the cream solder, and mounting the electronic component on the first insulating plate is performed simultaneously with the second cream solder. The And reflowing, a step of fixing the heat conductor on the first insulating plate, can be.

  According to the wiring board manufactured by this configuration, the heat generated by the electronic component is further transmitted through the solder (by cream solder), the first wiring pattern, and the solder (by the second cream solder). The state where the heat is accumulated in the electronic component is avoided. That is, more efficient heat dissipation of the electronic component can be achieved. Moreover, since the heat conductor for heat dissipation measures is attached and fixed to the electronic component in advance, it is not necessary to handle only the heat conductor alone thereafter, and the manufacturing efficiency is increased.

  Based on the above, embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view schematically showing a configuration of a component built-in wiring board according to an embodiment of the present invention.

  As shown in FIG. 1, this component built-in wiring board includes an insulating layer 11 (first insulating layer), 12, 12, 13, 14, and 15 (12, 13, 14, 15 second insulating layer). ), Wiring layer 21, 22 (wiring pattern), 23, 24 (third wiring pattern), 25 (second wiring pattern), 26 (= 6 layers in total), interlayer connector 31, 32, 34, 35, through-hole conductor 33, surface-mounted passive element component 41, electronic component (semiconductor element by wafer level / chip scale package) 42, thermal conductor (copper plate) 43, connecting member (solder) ) 51, a conductive member (solder) 52, a heat conducting member (solder) 53, solder resists 61 and 62, and a heat conducting member 34a.

  2 is a cross-sectional view schematically showing the structure of the component built-in wiring board at the position A-Aa shown in FIG. In the following description, FIG. 2 can also be referred to as appropriate. In FIG. 2, the same components as those shown in FIG. To supplement the relationship with FIG. 1, in FIG. 1, the thickness direction of the plate is drawn considerably larger than the actual for convenience of explanation. 1 and FIG. 2, the planar size relationship between the surface-mounted passive element component 41 and the electronic component 42 is actually considerably larger in the electronic component 42 (for example, 1 in length). About a digit) Large.

  This wiring board can have a surface-mounted passive element component 41 and an electronic component 42 as built-in electric / electronic components. Among these built-in components, in particular, the electronic component 42 has a built-in heat conductor 43 so as to surround it for the purpose of improving heat dissipation.

  The surface-mounted passive element component 41 is a so-called chip component, and here is, for example, a chip capacitor (or chip resistor, chip inductor). The planar size is, for example, 0.6 mm × 0.3 mm. Terminals 41 a are provided at both ends, and the lower side thereof is opposed to the mounting land formed by the wiring layer 22. The terminals 41 a of the surface mount type passive element component 41 and the mounting lands are electrically and mechanically connected by a connecting member (solder) 51.

  The electronic component 42 is, for example, a semiconductor element based on a wafer level / chip scale package, and includes at least a semiconductor chip and a grid-arranged surface mounting terminal 42a formed on the semiconductor chip. The surface mounting terminal 42a is a terminal provided by rearranging its position while being electrically conducted through a rewiring layer from a terminal (pad) originally provided on one surface of the semiconductor chip. By such rearrangement, the arrangement density as a terminal becomes coarser than that of the pad on the semiconductor chip. The electronic component 42 is mounted on a connection land formed by the wiring layer 22 via a conductive member (solder) 52 by surface mounting technology, and the electronic component 42 and the connection land are mechanically and electrically connected.

  In this embodiment, the heat conductor 43 is formed by processing a copper plate, but a plate of another material having good heat conductivity can also be used. In plan view, as shown in FIG. 2, the heat conductor 43 is adjacent to and spaced from the end face of the electronic component 42 (semiconductor chip), and is covered from the back surface of the semiconductor chip. Have been placed. These spaces are separated by an adhesive member 44 provided between them. If the adhesive member 44 is non-conductive, electrical contact between the heat conductor 43 and the electronic component 42 can be avoided. Alternatively, the adhesive member 44 can be positively conductive so that the potential of the substrate of the semiconductor element can be fixed from the heat conductor 43 side.

  The heat generated by the electronic component 42 moves from the end face and the back face of the semiconductor chip to the opposing faces of the heat conductor 43 through the layer of the adhesive member 44. This is one heat dissipation path for the heat generated by the electronic component 42. Further, the heat conductor 43 is fixed to the wiring layer 22 (fixing land thereof) by a heat conductive member (solder) 53, and these are mechanically and thermally connected. As a result, the heat generated by the electronic component 42 is further transferred to the heat conductor 43 via the conductive member 52, the wiring pattern 22, and the heat conducting member 53, and the heat is further accumulated in the electronic component 42. It is to be avoided. Note that the heat conductor 43 is actually electrically connected to the wiring layer 22, and when the adhesive member 44 is non-conductive, the heat conductor 43 is the electronic component 42. It is also possible to function as a shield member against the above.

  If the electronic component 42 and the heat conductor 43 are integrated in advance using the adhesive member 44, the entire integrated component can be handled as a new built-in component at the time of manufacture. That is, in that case, the terminal 42a of the electronic component 42 and the connection portion of the heat conductor 43 to the wiring layer 22 can be handled as a new set of terminals. Thereby, like the case of the electronic component 42 alone, the integrated component can be mounted on the wiring layer 22 by the surface mounting technique using the conductive members 52 and 53.

  It supplements about the processing method for obtaining the heat conductor 43. FIG. The heat conductor 43 can be obtained by performing each processing of giving an intended planar outer shape to the flat plate material and giving a concave portion that covers the electronic component 43. As the flat plate material, for example, a copper plate material having a thickness of 0.3 mm can be used, and both the outer shape formation and the concave portion formation can be performed by, for example, etching.

  For the formation of the outer shape, the flat plate material is etched so as to penetrate the plate thickness along the outer shape line. Regarding the formation of the recess, half etching is performed by using the control in the depth direction with respect to the region where the recess of the flat plate material is to be formed. The formation depth is, for example, 0.2 mm, assuming that the height of the electronic component 43 is less than 0.2 mm, for example, and the thickness of the adhesive member 44 is, for example, 20 μm. The etching process is preferable because it can efficiently perform a large amount of processing, but it is of course possible to use machining (cutting or counterboring).

  As shown in FIG. 2, it is preferable that the heat conductor 43 has a shape surrounding the entire circumference of the electronic component 43 as a heat conductor. However, it is also possible to radiate heat preferably by providing the heat conductor 43 so as to face the periphery and the back surface of the electronic component 43 that are close to a portion where heat generation is particularly large without surrounding the entire periphery. In any case, the heat conductor 43 has a surface facing away from the back surface of the semiconductor chip of the electronic component 43 and a surface facing away from the end face of the semiconductor chip. For this reason, the heat conductor 43 has a step surface facing the back surface of the semiconductor chip 43, a step surface higher than this step surface (used as a connection part to the wiring layer 22), and a rising surface connecting these step surfaces. It is processed to have.

  It is preferable for the purpose of heat dissipation that the planar shape of the heat conductor 43 is set as large as possible so as to avoid the area where the wiring patterns 23 and 24 are disposed. As shown in the figure, in the wiring board, the built-in components are provided in the opening of the central (core) insulating layer 13, and this opening allows the area of the wiring patterns 23 and 24 to be avoided. This is because the wiring patterns 23 and 24 are not provided. If the area of the wiring patterns 23 and 24 is avoided, however, the heat conductor 43 can be largely arranged in a wide area where the wiring patterns 23 and 24 are not arranged. Thereby, heat dissipation can be improved more.

  The heat conductor 43 is in contact with the heat conducting member 34 a on the surface opposite to the side on which the heat conducting member 53 is disposed, and the opposite side of the heat conducting member 34 a is in contact with the wiring layer 25. Therefore, the heat transferred from the electronic component 42 to the heat conductor 43 can also be transferred to other wiring layers via the heat conducting member 34a. Therefore, further improvement in heat dissipation is achieved. The heat conducting member 34a is made of the same material as the interlayer connector 34 and is formed by the same process as the interlayer connector 34 (described later). Therefore, even if the heat conducting member 34a is provided, a new process is not particularly required in assembling and manufacturing the wiring board, and the production efficiency is not lowered.

  For example, a conductive composition can be used for the conductive member 52 and the heat conducting member 53 instead of solder.

  Describing another structure as a component built-in wiring board, the wiring layers 21 and 26 are wiring layers on both main surfaces as a wiring board, and various components (not shown) can be mounted thereon. Solder resist 61 is provided on both main surfaces except for the land portions of the wiring layers 21 and 26 on which solder (not shown) is to be mounted in mounting, so that the solder melted at the time of solder connection is held on the land portions and thereafter functions as a protective layer. , 62 (thickness is about 20 μm, for example). An Ni / Au plating layer (not shown) with high corrosion resistance may be formed on the surface layer of the land portion.

  The wiring layers 22, 23, 24, and 25 are inner wiring layers, and the insulating layer 11 is disposed between the wiring layer 21 and the wiring layer 22, and the wiring layer 22 and the wiring layer 23 are sequentially disposed. The insulating layer 12 is insulated between the wiring layer 23 and the wiring layer 24, the insulating layer 14 is insulated between the wiring layer 24 and the wiring layer 25, and the insulating layer 14 is insulated between the wiring layer 25 and the wiring layer 26. Layers 15 are located and separate these wiring layers 21-26. Each of the wiring layers 21 to 26 is made of, for example, a metal (copper) foil having a thickness of 18 μm.

  Each of the insulating layers 11 to 15 is a rigid material made of, for example, a glass epoxy resin, for example, having a thickness of 100 μm, and the insulating layer 13 only having a thickness of, for example, 300 μm. In particular, the insulating layer 13 has openings at positions corresponding to the built-in surface mount passive element component 41, electronic component 42, and heat conductor 43, and provides a space for embedding them. The insulating layers 12 and 14 are deformed so as to fill the space inside the opening and the through-hole conductor 33 of the insulating layer 13, and there is no space serving as a gap inside.

  The wiring layer 21 and the wiring layer 22 can be conducted by an interlayer connector 31 that is sandwiched between the surfaces of the patterns and penetrates the insulating layer 11. Similarly, the wiring layer 22 and the wiring layer 23 can be conducted by an interlayer connector 32 that is sandwiched between the surfaces of the patterns and penetrates the insulating layer 12. The wiring layer 23 and the wiring layer 24 can be conducted by a through-hole conductor 33 provided through the insulating layer 13. The wiring layer 24 and the wiring layer 25 can be conducted by an interlayer insulator 34 that is sandwiched between the surfaces of these patterns and penetrates the insulating layer 14. The wiring layer 25 and the wiring layer 26 can be conducted by an interlayer connector 35 that is sandwiched between the surfaces of these patterns and penetrates the insulating layer 15.

  The interlayer connectors 31, 32, 34, and 35 (and the heat conducting member 34a) are derived from conductive bumps formed by screen printing of a conductive composition, and depend on the manufacturing process. The diameter changes in the direction (up and down lamination direction in FIG. 1). The diameter is, for example, 200 μm on the thick side.

  Next, a manufacturing process of the component built-in wiring board shown in FIGS. 1 and 2 will be described with reference to FIGS. 3 to 5 are process diagrams schematically showing a part of the manufacturing process of the component built-in wiring board shown in FIG. In these figures, the same or equivalent components as those shown in FIG.

  It demonstrates from FIG. FIG. 3 shows a manufacturing process of a portion centering on the insulating layer 11 in each configuration shown in FIG. First, as shown in FIG. 3 (a), a paste-like conductive composition to be an interlayer connection 31 is formed on a metal foil (electrolytic copper foil) 22A having a thickness of, for example, 18 μm by, for example, screen printing. It is formed in a bump shape (bottom diameter, for example, 200 μm, height, for example, 160 μm). This conductive composition is obtained by dispersing fine metal particles such as silver, gold and copper or fine carbon particles in a paste-like resin. For convenience of explanation, printing is performed on the lower surface of the metal foil 22A, but it may be printed on the upper surface (the following drawings are also the same). After the interlayer connector 31 is printed, it is dried and cured.

  Next, as shown in FIG. 3B, an FR-4 prepreg 11A having a thickness of, for example, 100 μm is laminated on the metal foil 22A to penetrate the interlayer connector 31 so that the head is exposed. To do. At the time of exposure or thereafter, the tip thereof may be crushed by plastic deformation (in any case, the shape of the interlayer connection body 31 has an axis that coincides with the stacking direction, and the diameter changes in the axial direction). Subsequently, as shown in FIG. 3C, a metal foil (electrolytic copper foil) 21A is laminated on the prepreg 11A, and the whole is integrated by pressing and heating. At this time, the metal foil 21A is in electrical continuity with the interlayer connector 31, and the prepreg 11A is completely cured to become the insulating layer 11.

  Next, as shown in FIG. 3 (d), the metal foil 22A on one side is subjected to patterning by, for example, well-known photolithography, and this is used as a heat conductor adjacent to a part connection (mounting) land and a part thereof. The wiring pattern 22 including the fixing land for 43 is processed. Then, as shown in FIG. 3 (e), cream solders 51A, 52A, and 53A are applied on the connecting lands obtained by processing and the fixing lands for the heat conductor 43. These can be applied using, for example, screen printing. Screen printing can be easily and efficiently printed in a predetermined pattern. In addition, it can replace with screen printing and can also apply with a dispenser.

  Next, the surface-mount type passive element component 41 and the electronic component 42 to which the heat conductor 43 is previously attached and fixed via the adhesive member 44 are placed on the lands via the cream solders 51A, 52A, and 53A, respectively. Each is mounted, for example, by a mounter. Subsequently, the cream solder 51A, 52A, 53A is reflowed by heating in a reflow furnace, for example. Due to the reflow of the cream solders 52A and 53A, even when there are some steps in the connection portions of the terminals 42a and the heat conductors 43 to the wiring layer 22, the molten solder fills this and a good connection is possible. .

  As described above, as shown in FIG. 3F, the surface-mounted passive element component 41 and the electronic component 42 with the heat conductor 43 are connected to the connection member 51, the conductive member 52, and the heat conductive member 53, respectively. Thus, the wiring board material 1 in a state of being connected to each land of the wiring layer 22 can be obtained. The subsequent process using the wiring board material 1 will be described with reference to FIG.

  Next, a description will be given with reference to FIG. FIG. 4 shows a manufacturing process of a part centering on the insulating layer 13 and the same 12 in each configuration shown in FIG. First, as shown in FIG. 4A, for example, an FR-4 insulating layer 13 having a thickness of, for example, 300 μm in which metal foils (electrolytic copper foils) 23A and 24A having a thickness of 18 μm are laminated on both surfaces is prepared. A through-hole 83 for forming a through-hole conductor is formed at a predetermined position, and the component mounting portions 81 and 82 are formed in portions corresponding to the surface-mounted passive element component 41, the electronic component 42, and the heat conductor 43. Form. The component opening 82 is a heat dissipation compatible component opening.

  Next, electroless plating and electrolytic plating are performed to form a through-hole conductor 33 on the inner wall of the through-hole 83 as shown in FIG. At this time, a conductor is also formed on the inner walls of the openings 81 and 82. Further, as shown in FIG. 4C, the metal foils 23A and 24A are patterned in a predetermined manner using well-known photolithography to form wiring layers 23 and 24. By patterning the wiring layers 23 and 24, the conductor formed on the inner walls of the openings 81 and 82 is also removed.

  Next, as shown in FIG. 4 (d), conductive bumps (bottom diameter: 200 μm, height: 160 μm, for example) that will become the interlayer connector 32 are formed at predetermined positions on the wiring layer 23 of the paste-like conductive composition. It is formed by screen printing. Subsequently, as shown in FIG. 4E, an FR-4 prepreg 12A (nominal thickness, for example, 100 μm) to be the insulating layer 12 is laminated on the wiring layer 23 side using a press. The prepreg 12 </ b> A is previously provided with openings corresponding to the built-in surface mount passive element component 41, electronic component 42, and thermal conductor 43, similar to the insulating layer 13.

  In the stacking step of FIG. 4 (e), the head of the interlayer connector 32 is made to penetrate the prepreg 12A. In addition, the broken line of the head part of the interlayer connection body 32 in FIG. 4E indicates that there are both cases where the head part is plastically deformed and crushed at this stage, and when it is not plastically deformed. The wiring board material obtained as described above is referred to as a wiring board material 2.

  The steps shown in FIG. 4 can be performed as follows. In the stage of FIG. 4A, only the through hole 83 is formed, and the subsequent steps from FIG. 4B to FIG. 4D are performed without forming the openings 81 and 82 for the built-in components. Next, as a process corresponding to FIG. 4E, prepreg 12A (without opening) is stacked. And it is the process of forming simultaneously the opening part for components incorporation in the insulating layer 13 and the prepreg 12A.

  Next, a description will be given with reference to FIG. FIG. 5 is a diagram showing an arrangement relationship in which the wiring board materials 1 and 2 obtained as described above are stacked. Here, the upper wiring board material 3 shown in the figure applies the same process as that of the lower wiring board material 1, and thereafter, the interlayer connector 34 and the prepreg 14A are connected to the interlayer connector in the intermediate wiring board material 2 shown in the figure. 32 and the prepreg 12A. In the wiring board material 3, the interlayer connector 34 and the heat conducting member 34a can be formed by the same process.

  However, the wiring board material 3 has a configuration without components (surface-mounted passive element component 41 and electronic component 42 with thermal conductor 43) and a portion (each land) for connecting the component, and prepreg 14A is not provided with an opening for the surface-mounted passive element component 41 and an opening for the electronic component 42 with the heat conductor 43. In addition, the metal foil (electrolytic copper foil) 26A, the insulating layer 15, the interlayer connection body 35, the wiring layer 25, the prepreg 14A, and the interlayer connection body 34 (heat conducting member 34a) are respectively the metal foil 21A of the wiring board material 1 and the insulation. It is the same as the layer 11, the interlayer connector 31, the wiring layer 22, the prepreg 12 </ b> A of the wiring board material 2, and the interlayer connector 32.

  The respective wiring board materials 1, 2, and 3 are laminated and arranged in the arrangement as shown in FIG. Thereby, the prepregs 12A and 14A are completely cured, and the whole is laminated and integrated. At this time, due to the fluidity of the prepregs 12 </ b> A and 14 </ b> A obtained by heating, the space around the surface-mounted passive element component 41, the electronic component 42, and the heat conductor 43, and the space inside the through-hole conductor 33 are prepreg 12A and 14A are deformed and no gap is generated. In addition, the wiring layers 22 and 24 are electrically connected to the interlayer connectors 32 and 34, respectively, and the heat conducting member 34a is plastically deformed and contacts the back surface of the heat conductor 43.

  After the laminating step shown in FIG. 5, the upper and lower metal foils 26A and 21A are patterned in a predetermined manner using well-known photolithography, and further, layers of solder resists 61 and 62 are formed, as shown in FIG. Such a component built-in wiring board can be obtained. In FIG. 5, the insulating layer 11 corresponds to a first insulating plate, the prepreg 12A and the insulating layer 13 correspond to a fourth insulating plate, the prepreg 14A corresponds to a third insulating plate, and the insulating layer 15 corresponds to a second insulating plate.

  As a modification, the through-hole conductor 33 provided in the intermediate insulating layer 13 can naturally have a configuration similar to the interlayer connector 31 or 32. Further, for the interlayer connectors 31, 32, 34, and 35, in addition to those derived from the conductive bumps printed by the conductive composition described above, for example, metal bumps formed by metal plate etching, conductive composition filling It is also possible to appropriately select and employ a connection body obtained from the above, a conductor bump formed by plating, or the like. In addition, the outer wiring layers 21 and 26 are formed at the stage of each wiring board material 1 and 3 (for example, at the stage of FIG. 3D) other than patterning after the last lamination step. May be.

  Next, FIG. 6 is a process diagram schematically showing a modification of the manufacturing process shown in FIG. In FIG. 6, parts that are the same as or equivalent to those already described are given the same reference numerals. More specifically, FIG. 6 shows a process of further processing the wiring board material 1 shown in FIG. 3 (f) and changing it to a new wiring board material 1 A that replaces the wiring board material 1. .

  First, FIG. 6A is exactly the same as FIG. 4F. Next, as shown in FIG. 6B, the surface exposed at this point of the wiring layer 22 and the surface exposed at this point of the thermal conductor 43 are roughened to obtain roughened surfaces. 22a, modified to a roughened surface 43a. Specifically, for example, a blackening reduction process or a microetching process can be employed. Examples of the micro-etching process include CZ processing (MEC product name) and bond film processing (Atotech product name).

  The wiring board material 1A having the form shown in FIG. 6B is used instead of the wiring board material 1 in the laminating process shown in FIG. In this lamination step, the surface of the wiring layer 22 is a roughened surface 22a, and the surface of the heat conductor 43 is also a roughened surface 43a. Therefore, the prepreg 12A, the prepreg 14A, the wiring layer 22, The mechanical connection reliability (adhesion) with the conductor 43 is improved. Thereby, reliability as a component built-in wiring board can be increased.

  Next, a component built-in wiring board according to another embodiment of the present invention will be described with reference to FIG. FIG. 7 is a longitudinal sectional view schematically showing the structure of a component built-in wiring board according to another embodiment. In the figure, the same or equivalent components as those already described are denoted by the same reference numerals. The description is omitted unless there is a matter to add to that portion.

  This embodiment is different from the embodiments shown in FIGS. 1 and 2 in that the heat conductor 43A has no connection portion to the wiring layer 22 at all. Other points are the same. In order to manufacture such a component built-in wiring board, the wiring board material 1B having the configuration shown in FIG. 8 may be used instead of the wiring board material 1 shown in FIG. This embodiment has a simple configuration in that the heat conductor 43A has no connection part to the wiring layer 22, and the heat dissipation of the electronic component 42 is reduced by the absence of a heat exhaust path through the connection part. To do. However, it can be adopted depending on the required degree of heat dissipation.

  To form the wiring board material 1B, the electronic component 42 and the heat conductor 43A are preliminarily attached to the electronic component 42 via the adhesive member 44 in the same manner as in the above embodiment. It is possible to adopt a procedure of mounting and fixing, and then mounting the integrated part on the wiring layer 22. Alternatively, a procedure in which only the electronic component 42 is first mounted on the wiring layer 22 and then the heat conductor 43A is attached and fixed via the adhesive member 44 so as to cover the electronic component 42 can be employed. The former procedure is considered to be more efficient as a procedure for obtaining the state shown in FIG. 8 because the heat conductor 43A is attached and fixed to the electronic component 42 in advance.

  Next, a component built-in wiring board according to still another embodiment of the present invention will be described with reference to FIG. FIG. 9 is a longitudinal sectional view schematically showing the structure of a component built-in wiring board according to still another embodiment. In the figure, the same or equivalent components as those already described are denoted by the same reference numerals. The description is omitted unless there is a matter to add to that portion.

  This embodiment is different from the embodiments shown in FIGS. 1 and 2 in that the built-in electronic component 42A is a semiconductor element flip-connected to the wiring layer 22 via a conductive bump 42b (conductive member). . In addition, the heat conductor 43A does not have any connection portion to the wiring layer 22 like the embodiment shown in FIG.

  In the electronic component 42A, conductive bumps 42b are formed in advance on terminals (pads; not shown) provided on the surface of the semiconductor chip for electrical and mechanical connection to the inner wiring layer 22. The wiring layer 22 is formed with a pattern for connecting a built-in component in alignment with the position of the conductive bump 42b. The conductive bump 42b is made of, for example, Au, and is previously formed in a stud shape on the terminal. An underfill resin 54 is filled between the electronic component 42A and the wiring layer 22 and the insulating layer 11 for mechanical and chemical protection of the flip connection portion.

  In order to manufacture the component built-in wiring board shown in FIG. 9, the wiring board material 1C having the structure shown in FIG. 10 may be used instead of the wiring board material 1 shown in FIG. In order to form the wiring board material 1C, the electronic component 42A and the heat conductor 43A are preliminarily attached and fixed to the electronic component 42A via the adhesive member 44. A procedure for flip mounting the integrated component on the wiring layer 22 can be adopted. Alternatively, it is possible to adopt a procedure in which only the electronic component 42A is flip-mounted on the wiring layer 22 first, and then the heat conductor 43A is attached and fixed via the adhesive member 44 so as to cover the electronic component 42A.

  The former procedure is considered to be more efficient as a procedure for obtaining the state shown in FIG. 10 because the heat conductor 43A is attached and fixed to the electronic component 42A in advance. In any case, the underfill resin 54 may be applied in advance on the region of the insulating layer 11 to be flip-connected, or after the electronic component 42A is flip-connected. And the insulating layer 11 and the wiring layer 22 can be formed by allowing a liquid state before curing to penetrate by the capillary effect.

  In this embodiment, as the heat conductor 43A, the use of the heat conductor 43 having a connection portion to the wiring layer 22 as in the embodiment shown in FIGS. 1 and 2 is avoided. This is a somewhat different process in which the flip connection is performed using a dedicated device, and it is considered difficult to connect to the wiring layer 22 with cream solder like the thermal conductor 43 without affecting this process. Because. However, when the demand for production efficiency is not so strict, the number of processes is considered to increase, but such a configuration is not impossible.

  DESCRIPTION OF SYMBOLS 1 ... Wiring board material, 1A, 1B, 1C ... Wiring board material, 2 ... Wiring board material, 3 ... Wiring board material, 11 ... Insulating layer, 11A ... Prepreg, 12 ... Insulating layer, 12A ... Prepreg, 13 ... Insulating layer , 14 ... insulating layer, 14A ... prepreg, 15 ... insulating layer, 21 ... wiring layer (wiring pattern), 21A ... metal foil (copper foil), 22 ... wiring layer (wiring pattern), 22A ... metal foil (copper foil) 22a ... roughened surface, 23 ... wiring layer (wiring pattern), 23A ... metal foil (copper foil), 24 ... wiring layer (wiring pattern), 24A ... metal foil (copper foil), 25 ... wiring layer (wiring pattern) ), 26... Wiring layer (wiring pattern), 26 A... Metal foil (copper foil), 31, 32, 34, 35... Interlayer connection (conductive bump by conductive composition printing), 33. 34a ... Heat conducting member (by conductive composition printing) Electrical bumps), 41... Surface mounted passive element parts, 41 a... Terminals, 42... Electronic parts (semiconductor elements by wafer level chip scale package), 42 a... Surface mounting terminals, 42 A .. electronic parts (bare chip semiconductor elements) , 42b ... conductive member (conductive bump), 43, 43A ... thermal conductor (copper plate), 43a ... roughened surface, 44 ... adhesive member, 51 ... connecting member (solder), 51A ... cream solder, 52 ... conductive member ( Solder or conductive composition), 52A ... cream solder, 53 ... heat conducting member (solder or conductive composition), 53A ... cream solder (second cream solder), 54 ... underfill resin, 61, 62 ... solder resist 81 ... Openings for components, 82 ... Openings for heat dissipation compatible components, 83 ... Through holes.

Claims (12)

A first insulating layer;
A second insulating layer positioned in a stack with respect to the first insulating layer;
An electronic component having a semiconductor chip that is embedded in the second insulating layer and has a first surface having a terminal and a second surface opposite to the first surface;
A first surface which is further embedded in the second insulating layer and which faces away from the second surface of the semiconductor chip; and a second surface which faces away from the end surface of the semiconductor chip and faces. A heat conductor;
An adhesive member provided between the electronic component and the thermal conductor;
A wiring pattern including the connection lands for the electronic component provided between the first insulating layer and the second insulating layer;
A conductive member that is electrically and mechanically connected between the electronic component and the connection land of the wiring pattern and electrically and mechanically connects the electronic component and the connection land. Component built-in wiring board.   The component built-in wiring board according to claim 1, wherein the heat conductor has a surface facing the entire circumference of the end face of the semiconductor chip as the first surface.   2. The component built-in wiring board according to claim 1, wherein the electronic component is flip-connected to the connection land of the wiring pattern via the conductive member. The wiring pattern includes a fixing land for the heat conductor,
A heat conducting member that is interposed between the heat conductor and the fixing land of the wiring pattern and that thermally and mechanically connects the heat conductor and the fixing land;
The component built-in wiring board according to claim 1, wherein the electronic component is an electronic component of a chip scale package.   The component built-in wiring board according to claim 4, wherein the conductive member and the heat conducting member are made of the same material.   The component built-in wiring board according to claim 1, wherein the heat conductor is copper as a material thereof.   The component built-in wiring board according to claim 6, wherein the heat conductor has a roughened surface. A second wiring pattern provided in the second insulating layer spaced apart from the third surface, with the surface opposite to the first surface of the thermal conductor as a third surface; ,
The component built-in wiring board according to claim 1, further comprising: a heat conducting member sandwiched between the third surface of the heat conductor and the second wiring pattern. A third wiring pattern provided in a layered manner with the second wiring pattern in the second insulating layer;
The second insulating layer passes through a part of the stacking direction and is sandwiched between the surface of the second wiring pattern and the surface of the third wiring pattern, and is made of a conductive composition and stacked. An interlayer connection body having an axis that coincides with the direction and having a shape whose diameter changes in the direction of the axis,
9. The component built-in wiring board according to claim 8, wherein the interlayer connector and the heat conducting member are conductive compositions made of the same material. An electronic component having a semiconductor chip having a first surface having terminals and a second surface opposite to the first surface is provided with a first step surface and a first step surface higher than the first step surface. A heat conductor having a second step surface and a rising surface connecting the first step surface and the second step surface, and the first step surface is opposed to the second surface of the semiconductor chip. And fixing and fixing via an adhesive member so that the rising surface faces the end surface of the semiconductor chip,
Patterning a first metal foil laminated on a first insulating plate, and forming a first wiring pattern including lands for mounting the electronic component;
Applying cream solder on the land;
Placing the electronic component on the land via the cream solder with the first surface side of the semiconductor chip facing down;
Reflowing the cream solder and mounting the electronic component on the first insulating plate;
Patterning a second metal foil different from the first metal foil laminated on a second insulating plate different from the first insulating plate, and forming a second wiring pattern;
Laminating a third insulating plate different from the first and second insulating plates on a side of the second insulating plate having the second wiring pattern;
The fourth, third, and second layers are stacked on the first insulating plate so that the electronic component and the heat conductor are embedded in a fourth insulating plate that is different from the first to third insulating plates. And a step of integrating the two insulating plates in the order of the stacking positions. The step of forming the first wiring pattern is a step of forming a second land for fixing the thermal conductor so as to be adjacent to the land;
The step of applying the cream solder is a step of applying a second cream solder on the second land;
The step of placing the electronic component on the land via the cream solder with the first surface side of the semiconductor chip facing down is the electronic component to which the thermal conductor is attached. The second step surface of the heat conductor is made to face the second land via the second cream solder,
The step of reflowing the cream solder and mounting the electronic component on the first insulating plate simultaneously reflows the second cream solder, and the thermal conductor is transferred to the first insulating plate. The method of manufacturing a component built-in wiring board according to claim 10, wherein the method is a step of fixing the wiring board on the component. An electronic component having a semiconductor chip having a first surface having terminals and a second surface opposite to the first surface is provided with a first step surface and a second step higher than the first step surface. A thermal conductor having a second step surface and a rising surface connecting the first step surface and the second step surface, and the first step surface is opposed to the second surface of the semiconductor chip. And fixing and fixing via an adhesive member so that the rising surface faces the end surface of the semiconductor chip,
Forming a conductive bump on the terminal of the semiconductor chip of the electronic component;
Patterning a first metal foil laminated on a first insulating plate and forming a first wiring pattern including a land for flip mounting the electronic component;
Flip mounting the electronic component on the first insulating plate so that the conductive bump faces the land; and
Patterning a second metal foil different from the first metal foil laminated on a second insulating plate different from the first insulating plate, and forming a second wiring pattern;
Laminating a third insulating plate different from the first and second insulating plates on a side of the second insulating plate having the second wiring pattern;
The fourth, third, and second layers are stacked on the first insulating plate so that the electronic component and the heat conductor are embedded in a fourth insulating plate that is different from the first to third insulating plates. And a step of integrating the two insulating plates in the order of the stacking positions.

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