JP4994988B2 - Wiring board manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a wiring board used for mounting electronic components such as semiconductor elements.

  Conventionally, there is a build-up wiring board as a high-density multilayer wiring board used for mounting electronic components such as semiconductor elements. FIG. 28 is a schematic cross-sectional view showing a general build-up wiring board. As shown in the figure, the build-up wiring board 80 includes a core board 83 having wiring conductors 82 made of copper foil on both surfaces of a glass-resin plate 81 having a thickness of about 0.2 to 2.0 mm, and the core. Insulating layers 84 made of a resin having a thickness of about 10 to 100 μm and wiring conductors 85 made of a plating film are alternately laminated on both surfaces of the substrate 83. Such a build-up wiring board 80 is manufactured by, for example, the following method.

  First, an insulating sheet in which a glass cloth is impregnated with a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin is prepared. Next, copper foil is stuck on both sides of the insulating sheet, and the thermosetting resin in the insulating sheet is thermoset to obtain a double-sided copper-clad plate. This double-sided copper-clad plate is drilled with through-holes that penetrate the upper and lower surfaces, and a plating film is deposited on the inner wall of the through-hole, and the copper foils on the upper and lower surfaces are electrically connected by the plating film in the through-holes. To do. Then, after filling the through hole with resin, the upper and lower copper foils are etched into a predetermined pattern to obtain a core substrate 83 having wiring conductors 82 made of copper foil on both surfaces of the glass-resin plate 81.

  Next, a resin film in which an inorganic insulating filler is dispersed in a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin is stuck on the upper and lower surfaces of the core substrate 83, and the thermosetting resin in the resin film is attached. The insulating layer 84 is formed by heat curing. Via holes are drilled in this insulating layer 84 by laser processing, and wiring conductors 85 made of a plating film are simultaneously formed on the surface of the insulating layer 84 including the inside of the via holes by a semi-additive method. Then, by repeating the formation of the next insulating layer 84 and the wiring conductor 85 a plurality of times, a core substrate 83 having wiring conductors 82 made of copper foil on both surfaces of the glass-resin plate 81 and both surfaces of the core substrate 83 are formed. A build-up wiring board 80 is produced in which insulating layers 84 made of a resin and wiring conductors 85 made of a plating film are alternately laminated.

  However, although such a build-up wiring board 80 is capable of high-density wiring, the glass-resin plate 81 having a thickness of about 0.2 to 2.0 mm is used as the core board 83. There was a problem that it was difficult to reduce the overall thickness.

  Therefore, in Patent Document 1, a wiring conductor and an insulating layer are sequentially formed on one surface side of a metal plate from the semiconductor element mounting surface side to the external connection terminal mounting surface side, and then the metal plate is etched away. Thus, a method of manufacturing a multilayer substrate for a semiconductor device has been proposed. According to the method disclosed in Patent Document 1, a semiconductor device mounting surface is flat and a thin multilayer substrate for a semiconductor device can be provided.

However, in the method described in Patent Document 1, it is necessary to etch away a metal plate that requires a relatively large thickness, and the etching takes a long time. Therefore, there was a problem to be solved that the production efficiency was low.
Japanese Patent No. 3635219

  The subject of this invention is providing the manufacturing method of the wiring board which can manufacture a thin and high-density wiring board efficiently.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found a solution means having the following constitution and have completed the present invention.
(1) A plurality of insulating layers and conductor layers are alternately laminated on the metal foil of the metal foil with a support film, on which the metal foil is held via an adhesive layer on the support film, and the metal foil and the insulation A method of manufacturing a wiring board, comprising: a step of forming a laminated body for a wiring board comprising a layer and the conductor layer; and a step of separating the laminated body from the support film.
(2) A step of laminating the metal foil with a support film on the main surface of the support substrate having a flat main surface so that the upper surface of the metal foil is exposed before the step of forming the laminate. A plurality of insulating layers and conductor layers are alternately stacked on the exposed upper surface of the metal foil to form a laminate for a wiring board comprising the metal foil, the insulating layer, and the conductor layer. (1) The manufacturing method of the wiring board as described.
(3) The step of laminating the metal foil with the support film on the main surface of the support substrate further includes exposing a metal frame surrounding the metal foil to an outer peripheral portion of the main surface of the support substrate, and exposing an upper surface of the metal frame. The method for manufacturing a wiring board according to (2), including a step of laminating as described above.
(4) The step of forming the laminate includes an exposed upper surface of the metal foil, an exposed upper surface of the metal frame, and a main surface of the support substrate exposed from between the metal foil and the metal frame. Insulating layers and conductor layers are alternately laminated to form a laminate for a wiring board comprising the metal foil, the insulating layer, and the conductor layer, and the laminate is separated from the support film. The method for manufacturing a wiring board according to (3), including a step of cutting the stacked body and the support substrate located in an inner region of the metal frame before the step of performing.

(5) The method for manufacturing a wiring board according to any one of (1) to (4), including a step of etching the metal foil into a predetermined pattern after separating the laminate from the support film.
(6) A step of forming a pad for external connection on the metal foil is included before the step of forming the laminate, and an insulating layer and a conductor layer are formed on the metal foil on which the pad for external connection is formed. A plurality of layers alternately stacked to form a laminate for a wiring board comprising the metal foil, the insulating layer, the conductor layer, and the pad for external connection, and the support The method of manufacturing a wiring board according to (1), wherein in the step of separating from the film, and in the separated laminate, all of the metal foil is etched away to expose the external connection pads.

  According to said (1), it has the effect that a thin and high-density wiring board can be manufactured efficiently. That is, according to the above (1), the metal foil is formed by alternately laminating a plurality of insulating layers and conductor layers on the metal foil of the metal foil with a support film in which the metal foil is held on the support film via the adhesive layer. Forming a laminate for a wiring board composed of a foil, the insulating layer, and the conductor layer, so there is no problem that the entire thickness of the wiring board cannot be reduced by using the core substrate, and it is thin and dense. A wiring board can be provided.

  And when separating the formed laminated body from the said support film, since the said metal foil with a support film only hold | maintains the metal foil on the support film via the adhesion layer, a support film and metal foil The laminate can be easily separated in a short time without damaging the laminate by simply peeling off the gap between the two, and thereby a thin and high-density wiring board can be efficiently manufactured.

In particular, according to the above (2), since the support substrate is used in addition to the support film, the stability when the wiring substrate is manufactured can be improved.
According to the above (3), the metal frame surrounding the metal foil with the support film is laminated on the outer peripheral portion of the main surface of the support substrate so that the upper surface of the metal frame is exposed. Therefore, the wiring board according to the present invention can be efficiently manufactured. After forming the laminate, the metal frame can be removed by cutting the laminate and the support substrate located in the inner region of the metal frame as described in (4).
The metal foil constituting the laminate can be used as a part of a wiring conductor after being etched into a predetermined pattern as described in (5).

  Hereinafter, an embodiment of a method for manufacturing a wiring board according to the present invention will be described in detail with reference to the drawings. FIGS. 1-11 is a figure for every process which shows the manufacturing method of the wiring board concerning this embodiment. More specifically, among these drawings, FIG. 1 is a schematic cross-sectional view showing a process of preparing the prepreg 3P for the support substrate 3, the metal foil 2 with the support film, and the metal frame 4. FIG. 2 is a schematic cross-sectional view showing a state in which the metal foil 2 with support film and the metal frame 4 are placed on the prepreg 3P for the support substrate 3. 3A is a schematic cross-sectional view showing a state in which the metal foil 2 with a support film 2 and the metal frame 4 are laminated on the main surface of the support substrate 3, and FIG. 3B is a schematic perspective view showing the state. FIG. FIG. 4A is a schematic cross-sectional view showing a state in which the first insulating layer 21 is laminated on the metal foil 2 with the support film and the periphery thereof, and FIG. 4B is a diagram illustrating the first insulating layer 21. It is a top view which shows the notch part 30 formed in. FIG. 5 is a schematic cross-sectional view showing a state in which the second conductor layer 12 is formed on the first insulating layer 21. FIG. 6 shows the second to fourth insulating layers 22 to 24 for interlayer insulation and the third to fifth conductor layers 13 to 13 for wiring conductors on the first insulating layer 21 and the second conductor layer 12. 15 is a schematic cross-sectional view showing a state in which a laminated body 10 for a wiring board is formed by alternately forming 15 and 15 and forming a solder resist fifth insulating layer 25 thereon. FIG. 7 is a schematic cross-sectional view showing a process of cutting out the central portion of the laminate 10, the support film 2, and the support substrate 3. FIG. 8 is a schematic cross-sectional view showing the center portion of the laminated body 10, the support film 2, and the support substrate 3 that have been cut out. FIG. 9 is a schematic cross-sectional view showing a process of separating the cut-out laminate 10 from the support film 1. FIG. 10 is a schematic cross-sectional view showing the process of forming the wiring conductor on the surface of the first insulating layer 21 by etching the first conductor layer 11. FIG. 11 is a schematic cross-sectional view showing a process of forming a sixth insulating layer 26 for solder resist on the surfaces of the etched metal foil 11 and the first insulating layer 21.

  First, as shown in FIG. 1, the metal foil 2 with a support film, the prepreg 3P for the support substrate 3, and the metal frame 4 are prepared. The metal foil 2 with a support film is obtained by holding the metal foil 11 on the support film 1 via an adhesive layer (not shown).

  The support film 1 has a thickness of about 10 to 100 μm and effectively prevents the metal foil 11 from being broken or wrinkled, and facilitates handling of the metal foil 11. The support film 1 is preferably made of a heat resistant resin such as a polyester resin. Specific examples include a polyethylene terephthalate (PET) film.

  The metal foil 11 is for providing a conductor layer that is a starting point in the production of a wiring board. The metal foil 11 is preferably made of a highly conductive metal such as copper (copper foil). As thickness of the metal foil 11, about 1-35 micrometers is mentioned, for example. Thereby, when this metal foil 11 is removed by etching, it can be removed by etching in a short time. Further, the metal foil 11 having such a thickness does not need to be removed by etching, and can be suitably used as a part of a wiring conductor (pad for external connection) by etching into a predetermined pattern. On the other hand, when the thickness of the metal foil 11 is thinner than 1 μm, the strength of the metal foil 11 is lowered, and workability when a plurality of insulating layers and conductor layers are alternately laminated on the metal foil 11 may be lowered. If the thickness is larger than 35 μm, the thickness becomes unnecessarily thick, and the time required for etching removal becomes longer, which is not preferable.

  The pressure-sensitive adhesive layer is preferably made of a heat-resistant pressure-sensitive adhesive material such as a silicone resin-based resin, an acrylic resin-based resin, or a polyorganosiloxane resin-based material in order to withstand the heat load applied during the production of the wiring board. The pressure-sensitive adhesive layer has a thickness of about 0.01 to 1.0 μm and an adhesive strength of 1 to 10 N in order to separate from the support film 1 without damaging the laminate 10 for a wiring board described later. / M is preferable.

  The prepreg 3P serves as a support substrate 3 for supporting the laminate 10 while maintaining the necessary flatness when the laminate 10 for a wiring board described later is manufactured, and a support film is provided on the main surface thereof. The attached metal foil 2 and the metal frame 4 are placed and heated while pressing them from above and below, whereby the metal foil 2 and the metal frame 4 with a support film are laminated on the prepreg 3P and are thermoset in that state. The prepreg 3P is generally formed of a substantially rectangular flat plate having a thickness of about 0.2 to 2.0 mm and a side length of about 300 to 1000 mm, but is not limited thereto. As the prepreg 3P, for example, a woven fabric made of heat-resistant fibers such as glass fibers is impregnated with a thermosetting resin such as an epoxy resin to form a semi-cured sheet.

  The metal frame 4 is for use as a charge supply electrode for plating when manufacturing a laminate 10 for a wiring board to be described later, and has a thickness of about 12 to 35 μm. The metal frame 4 is preferably made of a highly conductive metal such as copper.

  After preparing each material as described above, as shown in FIG. 2, the metal foil 2 with a support film is placed on the center of the main surface of the prepreg 3P, and the support film 1 faces the main surface of the prepreg 3P. While arrange | positioning, the metal frame 4 is arrange | positioned on the main surface outer peripheral part of the prepreg 3P. Then, while pressing them from above and below at a pressure of 0.5 to 9 MPa, and heating them at a temperature of 130 to 200 ° C. for about 30 to 120 minutes, as shown in FIGS. 3A and 3B, While laminating the metal foil 2 with a support film on the main surface of the support substrate 3 formed by thermosetting 3P so that the upper surface of the metal foil 11 is exposed, on the outer periphery of the main surface of the support substrate 3, The metal frame 4 surrounding the metal foil 11 is laminated with its upper surface exposed.

  After the lamination, the upper surface of the exposed metal foil 11, the upper surface of the exposed metal frame 4, and the main surface of the support substrate 3 exposed from between the metal foil 11 and the metal frame 4 are substantially the same height. become. Thereby, since the laminated body 10 for wiring boards which will be described later can be supported on a surface having excellent flatness, the laminated body 10 can be obtained while suppressing the occurrence of warpage and undulation associated with processing. The upper surface of the exposed metal foil 11, the upper surface of the metal frame 4, and the main surface of the support substrate 3 exposed from between the metal foil 11 and the metal frame 4 do not have to be completely the same height. There may be a height difference of 5 μm or less between them.

  Next, as shown in FIG. 4A, the exposed upper surface of the exposed metal foil (first conductor layer) 11, the exposed upper surface of the metal frame 4, and between the metal foil 11 and the metal frame 4 are exposed. A first insulating layer 21 for interlayer insulation is laminated on the main surface of the support substrate 3. As shown in FIG. 4B, the first insulating layer 21 has notches 30 that expose a part of the outer peripheral side of the metal frame 4 at two locations in the circumferential direction of the first insulating layer 21. It is formed to face each other. The first insulating layer 21 is made of an electrically insulating material in which an inorganic insulating filler such as silica or talc is dispersed in a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin. Alternatively, an electrically insulating material in which a glass cloth is impregnated with a thermosetting resin may be used.

  Such a first insulating layer 21 is, for example, an exposed metal obtained by pasting a mixture obtained by dispersing an inorganic insulating filler into an uncured material of a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin. After coating on the upper surface of the foil 11, the upper surface of the exposed metal frame 4 (excluding the position corresponding to the notch 30), and the main surface of the support substrate 3 exposed from between the metal foil 11 and the metal frame 4. It is formed by thermosetting. Moreover, it is not limited to this, For example, what made the said mixture into a film form, and the prepreg which impregnated uncured thermosetting resin to the glass cloth, the upper surface of the exposed metal foil 11, the exposed metal frame 4 is attached to the main surface of the support substrate 3 exposed from the upper surface (excluding the position corresponding to the notch 30) and between the metal foil 11 and the metal frame 4 and then thermally cured. Also good.

  In the first insulating layer 21, a via opening V for exposing a part of the metal foil 11 is formed. The opening V is formed by, for example, laser processing. Alternatively, the mixture for the first resin layer 21 may be photosensitive, and may be formed by subjecting it to exposure / development processing using a photolithography technique, but is not limited thereto. Absent.

  Next, as shown in FIG. 5, the second conductor layer 12 for the wiring conductor is formed in a predetermined pattern in the surface of the first insulating layer 21 and in the opening V. The second conductor layer 12 is made of, for example, an electroless copper plating film or an electrolytic copper plating film, and is preferably formed by a known semi-additive method. Since the semi-additive method is excellent in fine wiring, it is suitable for efficiently manufacturing a thin and high-density wiring board. Specifically, the surface of the first insulating layer 21 is first roughened as necessary, and then an electroless copper plating film is deposited on the surface to a thickness of about 0.1 to 2.0 μm. At this time, an electroless copper plating film is deposited on the surface of the metal frame 4 exposed from the notch 30 to a thickness of about 0.1 to 2.0 μm.

Next, a plating resist layer having an opening corresponding to the second conductor layer 12 is formed on the surface of the electroless copper plating film deposited on the surface of the first insulating layer 21. The plating resist layer has the opening by sticking a photosensitive resin film on the electroless copper plating film and subjecting the resin film to exposure / development processing using a photolithography technique. Formed. Next, the electrolytic copper plating film is deposited to a thickness of about 5 to 30 μm on the electroless copper plating film exposed in the opening of the plating resist layer. At this time, the metal frame 4 exposed from the notch 30 can be used as a charge supply electrode for supplying a charge for electrolytic plating. Thereby, the metal frame 4 and the cathode of an electroplating apparatus can be electrically connected reliably. On the other hand, in the absence of the metal frame 4, the terminals of the electroplating apparatus are connected to an extremely thin electroless copper plating film, and the electroless copper plating film is rubbed or broken, making it difficult to stably supply power. become.
Next, after peeling off the plating resist layer, the exposed portion of the electroless copper plating film and the electrolytic copper plating film is etched entirely until the electroless copper plating film between the electrolytic copper plating films disappears to form a second The conductor layer 12 is formed.

  After the second conductor layer 12 is formed in this way, as shown in FIG. 6, second to fourth insulating layers for interlayer insulation are formed on the first insulating layer 21 and the second conductor layer 12. 22 to 24 and third to fifth conductor layers 13 to 15 for wiring conductors are alternately formed, and a fifth insulating layer 25 for solder resist is further formed thereon to form a wiring board. The laminated body 10 is formed.

  The second to fourth insulating layers 22 to 24 for interlayer insulation are made of the same electrical insulating material as that of the first insulating layer 21 and can be formed by the same method as that for the first insulating layer 21. Further, the third to fifth conductor layers 13 to 15 for the wiring conductor are composed of an electroless copper plating film and an electrolytic copper plating film similar to the second conductor layer 12, and are similar to the second conductor layer 12. It is preferable to form by a semi-additive method. Furthermore, the fifth insulating layer 25 for solder resist is made of an electrically insulating material in which an inorganic powder filler such as silica or talc is dispersed in an acrylic modified epoxy resin, for example, in an amount of 30 to 70% by mass. A photosensitive resin paste in which an inorganic insulating filler such as silica or talc is mixed into a mixture of a photosensitive resin and a photopolymerization initiator is screened on the fourth insulating layer 24 and the fifth conductor layer 15. It is applied to a thickness of about 10 to 30 μm by printing, roll coating, etc., and then formed by exposing and developing to a predetermined pattern using a photolithographic technique, followed by ultraviolet curing and heat curing. Is preferred.

  Next, as shown in FIG. 7, the laminate 10 and the support substrate 3 located in the inner region of the metal frame 4 are cut. In order to efficiently perform such cutting, the laminate 10, the support film 1, and the support substrate 3 are cut at a portion located 10 to 30 mm inside from the outer periphery of the metal foil 11, and as shown in FIG. It is preferable to cut out the central portion of 10 together with the support film 1 and the support substrate 3. The cutting method is arbitrary as long as the effect of the present invention is not hindered. For example, the cutting may be performed using a dicing or a router device.

  Next, as shown in FIG. 9, the cut laminate 10 is separated from the support film 1. In this separation, since the metal foil 11 is only held on the support film 1 via an adhesive layer (not shown), the laminate 10 can be damaged only by peeling off the support film 1 and the metal foil 11. And can be easily separated.

  Next, as shown in FIG. 10, an etching process for etching the metal foil (first conductor layer) 11 into a predetermined pattern is performed to form a wiring conductor (pad for external connection) on the surface of the first insulating layer 21. Form. In order to etch the metal foil 11 into a predetermined pattern, for example, an etching resist layer having a shape corresponding to the wiring conductor is formed on the surface of the metal foil 11, and the metal foil 11 exposed from the etching resist layer is removed by etching. Good. The etching resist layer has a shape corresponding to the wiring conductor by sticking a photosensitive resin film on the metal foil 11 and subjecting the resin film to exposure / development processing using a photolithography technique. After the metal foil 11 is etched, it is peeled off.

  Finally, as shown in FIG. 11, a sixth insulating layer 26 for solder resist is formed on the surfaces of the etched metal foil 11 and the first insulating layer 21 to obtain the wiring board 20 according to the present embodiment. . Thus, according to the present embodiment, the laminated body 10 is not directly formed on the support substrate 3, but the metal foil 2 with the support film is first exposed on the main surface of the support substrate 3. Thus, the laminated film 10 is obtained by alternately laminating a plurality of insulating layers and conductor layers on the metal foil 11, so that the support film 1 of the metal foil 2 with the support film is laminated with the laminate 10 and the support substrate. 3 can be made to function as a boundary layer for facilitating the separation, and as a result, the laminate 10 can be easily separated from the support substrate 3 in a short time. Moreover, the metal foil 11 can be used as a part of the wiring conductor after being etched into a predetermined pattern. Therefore, according to the present embodiment, the thin and high-density wiring board 20 can be efficiently manufactured. Note that the sixth insulating layer 26 for solder resist is made of the same material as the fifth insulating layer 25 and is formed by the same method as the fifth insulating layer 25.

  In the above-described embodiment, the case where the laminated body 10 for the wiring substrate is formed on one support substrate 3 has been described. However, as another embodiment according to the present invention, for example, two support substrates 3 are back to back. The laminated body 10 for the wiring board may be simultaneously formed on the outer main surface of each support substrate 3. FIG. 12 is a schematic cross-sectional view illustrating the method for manufacturing the wiring board according to the present embodiment, and corresponds to FIG. 1 described above. In FIG. 12, the same components as those in FIGS. 1 to 11 described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 12, the process of forming the laminated body 10 concerning this embodiment first, the metal foil 2 with a support film, the prepreg 3P for the support substrate 3, the metal frame 4, and the separation film 5 and Prepare two each. The separation film 5 functions as a boundary layer for easily separating the two support substrates 3 from each other after the laminated body 10 is formed on each support substrate 3. The separation film 5 is preferably made of a metal foil such as a copper foil or a heat resistant film such as a polyethylene terephthalate (PET) film. The thickness of the separation film 5 is preferably about 1 to 35 μm, for example.

  After preparing each material including such a separation film 5, a laminate 10 is obtained as shown in FIGS. 13 to 18, and a wiring substrate 20 is obtained using the laminate 10. That is, as shown in FIG. 13, two separation films 5 are sandwiched and sandwiched between the central portions of the two prepregs 3P, and the metal foil 2 with a support film is provided on the central portion of the main surface outside each prepreg 3P. And the metal frame 4 is arrange | positioned at the outer peripheral part of the said outer main surface, respectively. Next, by heating them while pressing them from above and below, as shown in FIG. 14, the two separation films 5 are sandwiched between the two support substrates 3 formed and integrated by thermosetting the prepreg 3P. Are overlapped with each other, and a metal foil 2 with a support film and a metal frame 4 are laminated on the outer main surface of each support substrate 3. At this time, the two separation films 5 are not bonded to each other, and are bonded only to the support substrate 3.

  Next, as shown in FIG. 15, the laminated body 10 for the wiring board is simultaneously formed on each outer main surface of the two support substrates 3. In addition, formation of each laminated body 10 is performed similarly to the process demonstrated based on FIGS. 4-6 in the said one Embodiment.

  Next, as shown in FIG. 16, the laminate 10, the support film 1, the support substrate 3, and the separation film 5 are cut at a portion located 10 to 30 mm inside from the outer periphery of the metal foil 11, thereby obtaining FIG. 17. As shown, the central part of each laminate 10 is cut out together with the support film 1, the support substrate 3 and the release film 5. At this time, since the release films 5 are not bonded to each other, both are easily separated.

  Next, as shown in FIG. 18, each cut-out laminated body 10 is separated from the support film 1 in the same manner as in the embodiment. Thereby, since the two laminated bodies 10 can be obtained, the efficiency at the time of forming the laminated body 10 can be improved about twice compared with the said one Embodiment. Then, two wiring boards 20 are obtained by subjecting each separated laminated body 10 to the process described based on FIGS. 10 and 11 in the embodiment. Therefore, according to the present embodiment, the thin and high-density wiring board 20 can be manufactured more efficiently.

  As still another embodiment according to the present invention, two support substrates 3 are overlapped with another separation substrate interposed between them to facilitate separation of the two, and the outside of each support substrate 3. A laminate 10 for a wiring board may be simultaneously formed on the main surface. FIG. 19 is a schematic cross-sectional view showing the method for manufacturing the wiring board according to the present embodiment, and corresponds to FIGS. 1 and 12 described above. In FIG. 19, the same components as those shown in FIGS.

  As shown in FIG. 19, the step of forming the laminated body 10 according to the present embodiment first includes a metal foil 2 with a support film, a prepreg 3P for a support substrate 3, a metal frame 4, and a separation film 5. Are prepared two by two, and one separation substrate 6 is prepared. The separation substrate 6 functions as a boundary layer for easily separating the two support substrates 3 from each other after the laminated body 10 is formed on each support substrate 3. The separation substrate 6 is made of, for example, a double-sided copper-clad plate in which a copper foil 8 having a thickness of about 12 to 35 μm is laminated on both surfaces of a glass-epoxy plate 7 having a thickness of about 50 to 400 μm.

  After preparing each material including such a separation substrate 6, a laminate 10 is obtained as shown in FIGS. 20 to 24, and a wiring substrate 20 is obtained using the laminate 10. That is, as shown in FIG. 20, the separation substrate 6 is sandwiched between the two prepregs 3P, and the separation film 5 is disposed at the center between the separation substrate 6 and the prepreg 3P. A metal foil 2 with a support film is disposed on the outer main surface central portion, and a metal frame 4 is disposed on the outer peripheral portion of the outer main surface.

  Next, by heating them while pressing them from above and below, as shown in FIG. 21, the separation substrate 6 is laminated and integrated between the two support substrates 3 on which the prepreg 3P is thermally cured, and for separation. The separation film 5 is sealed between the substrate 6 and the support substrate 3, and the metal foil 2 with support film and the metal frame 4 are laminated on the outer main surface of each support substrate 3. At this time, the separation substrate 6 and the separation film 5 are not bonded to each other, and are bonded only to the support substrate 3.

  Next, as shown in FIG. 22, wiring board laminates 10 are simultaneously formed on the respective outer principal surfaces of the two support substrates 3. In addition, formation of each laminated body 10 is performed similarly to the process demonstrated based on FIGS. 4-6 in the said one Embodiment.

  Next, as shown in FIG. 23, the laminate 10, the support film 1, the support substrate 3, the separation film 5, and the separation substrate 6 are cut at a portion located 10 to 30 mm inside from the outer periphery of the metal foil 11. Thus, as shown in FIG. 24, the central portion of each laminate 10 is cut out together with the support film 1, the support substrate 3, and the release film 5. At this time, since the separation film 5 and the separation substrate 6 are not bonded, they are easily separated.

  Next, the cut laminate 10 is separated from the support film 1 in the same manner as described based on FIG. Thereby, since the two laminated bodies 10 can be obtained, the efficiency which forms the laminated body 10 can be raised about 2 time compared with the said one Embodiment. Then, two wiring boards 20 are obtained by subjecting each separated laminated body 10 to the process described based on FIGS. 10 and 11 in the embodiment. Therefore, according to the present embodiment, the thin and high-density wiring board 20 can be manufactured more efficiently.

  Thus, according to the method for manufacturing a wiring board of the present invention, a thin and high-density wiring board can be efficiently manufactured. It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention. For example, in the above-described embodiments, the case where the metal foil 11 is etched into a predetermined pattern and used as a part of the wiring conductor has been described. However, the present invention is not limited to this, and FIG. As shown in FIG. 4, the metal foil 11 may be entirely removed by etching as necessary. In this case, the conductor layer 12 exposed in the via of the insulating layer 21 becomes a pad for external connection.

  Furthermore, as shown in FIG. 26, a pad P for external connection made of, for example, copper or the like is formed on the metal foil 11 by a semi-additive method or a full additive method, and the insulating layers 21 to 25 are formed thereon. The conductor layers 12 to 15 are alternately laminated to form a laminate 10 for a wiring board including the pad P as a constituent element, which is cut out and separated from the support film 1, and then, as shown in FIG. The pad 11 may be exposed by etching away all of the foil 11.

  In the case where the metal frame 4 is used as the charge supply electrode, the case where the notched portion 30 is formed in the insulating layer 21 has been described. However, instead of the notched portion 30, for example, all the outer peripheral sides of the metal frame 4 are frame-shaped. The insulating layer 21 may be laminated so as to be exposed.

It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. (A) is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention, (b) is the schematic perspective view. (A) is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention, (b) is the top view. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on other embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing which shows the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing for demonstrating the manufacturing process of the wiring board which concerns on further another embodiment of this invention. It is a schematic sectional drawing which shows a general buildup wiring board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support film 2 Metal foil with support film 3P prepreg 3 Support substrate 4 Metal frame 5 Separation film 6 Separation board 10 Laminate for wiring board 11 Metal foil 12-15 Conductive layer 21-26 Insulating layer 20 Wiring board 30 Notch Part

Claims (4)

A metal foil with a support film, in which the metal foil is held on the support film via an adhesive layer, is exposed on the center of the main surface of the support substrate, the main surface is exposed around the metal foil, and the upper surface of the metal foil Laminating so as to be exposed at substantially the same height as the main surface around the metal foil, and on the exposed upper surface of the metal foil and the exposed main surface of the support substrate , an insulating layer and a conductor A plurality of layers are alternately laminated to form a laminate for a wiring board comprising the metal foil, the insulating layer, and the conductor layer; and the laminate, the support film, and the support substrate and cut with a portion located from the outer periphery of the foil on the inside, that the step of cutting a central portion of the laminate together with the supporting film and the supporting substrate, the cut-out of the laminate is performed and separating from the support film The Method for manufacturing a wiring board according to symptoms. The step of laminating the metal foil with the support film on the main surface of the support substrate further includes a metal frame surrounding the metal foil on the outer peripheral portion of the main surface of the support substrate, and an upper surface of the metal frame of the metal foil. a method for manufacturing a wiring board according to claim 1, further comprising the step of laminating so as to expose at said main surface and substantially the same height as the surrounding. After separation of the laminate from the support film, method of manufacturing a wiring board according to claim 1 or 2 comprising the step of etching the metal foil into a predetermined pattern. Including a step of forming a pad for external connection on the metal foil before the step of forming the laminate,
A plurality of insulating layers and conductor layers are alternately laminated on the metal foil on which the pads for external connection are formed, and the metal foil, the insulating layers, the conductor layers, and the pads for external connection. Forming a laminate for a wiring board comprising:
Separating the laminate from the support film;
In separate the laminate, all of the metal foil is removed by etching, method of manufacturing a wiring board according to claim 1 further comprising the step of exposing the pads for the external connection.

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