JP4684454B2 - Printed wiring board manufacturing method and printed wiring board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wiring board, and more particularly, to a fine pattern-compatible multilayer printed wiring board corresponding to high-density mounting and a multilayer wiring board for MCM-L (multi-chip module) package.
[0002]
[Prior art]
As one of the conventional methods for producing a multilayer board, a “penetration method” in which a conical interlayer connection member is penetrated in the thickness direction of an insulating material substrate provided with a wiring pattern on both sides to form an interlayer connection of the wiring pattern. The method called is known. In this penetration method, a conductive bump group is formed by forming a conductive paste in which a conductive material such as metal fine particles is dispersed in a resin on a conductive plate such as a thin metal plate to form a substantially conical shape. A sheet-like insulating material substrate impregnated with a matrix material such as an epoxy resin is superimposed on a prepreg, that is, a reinforcing material such as a glass fiber sheet, on the side, and the conductor bumps are passed through the prepreg by pressing the conductor plate and the prepreg. This is a method of forming electrical conduction in the thickness direction of the insulating material substrate. FIG. 12 is a cross-sectional view schematically showing a manufacturing process of a printed wiring board manufactured by a penetration method. In this penetration method, as shown in FIG. 12 (a), a conductive bump 2 is formed on a copper foil 1 with a conductive paste, and then a prepreg 3 is stacked and pressed as shown in FIG. 12 (b). Conductor bumps 2 are penetrated in the thickness direction to form a resin-coated copper foil 4 as shown in FIG. 12 (c), and another copper foil 102 is overlaid thereon and pressed under heating to be double-sided copper-clad. A plate 502 is created (FIG. 12E), circuit formation is performed, and a double-sided substrate 602 is created by the penetration method. FIG. 13A is a view in which copper foils 401 and 402 made in the same manner as the resin-coated copper foil 4 in FIG. When a lamination press for pressurizing this under heating is performed, a four-layer substrate 702 as shown in FIG. 13B can be formed. Similarly, as shown in FIG. 14 (a), when a laminating press is performed in which the resin-coated copper foils 4 (403, 404) are pressed under heating, a six-layer substrate 8 by a penetration method as shown in FIG. 14 (b). Can be formed. Since the multilayer substrate 8 does not require plating, the copper layer on the surface can be finished in a thin state, so that a fine pattern can be formed. Further, since the vias 9 can be arranged randomly, there is an advantage that the wiring density of the inner layer can be increased and the substrate area can be reduced.
[0003]
[Problems to be solved by the invention]
However, in this substrate manufacturing method by the penetration method, the number of lamination presses increases as the number of lamination steps increases, so that the thermal history acts excessively on the material located inside, and in particular, microcracks occur in the insulating material substrate. Further, there is a problem in quality that peeling occurs at the interface between the stacked layers, which in turn causes deterioration of insulating characteristics and migration of patterned copper. In addition, a manufacturing process in which the number of times of laminating presses increases the number of man-hours and raises the manufacturing cost, and the manufacturing process in which the positional deviation between each layer must be controlled for each laminating press and the yield is poor. There is a problem above.
[0004]
In order to solve the above problem, a method of reducing the number of times of laminating press to one has been proposed. The method will be described with reference to FIGS. First, the insulating material substrate-attached copper foil 4 is prepared as shown in FIGS. Up to this point, the process is the same as FIGS. 12A to 12C, and the insulating material substrate is not cured at this point. When the copper foil 4 with the insulating material substrate having the flat tip of the conductor bump is laminated with the resist film 11, the state shown in FIG. When this is selectively exposed and developed (not shown) and the copper foil is etched, a resin-coated copper foil 12 having a pattern 1a as shown in FIG. 15E can be formed. As shown in FIG. 16, the resin-coated copper foils 1201, 1202, 1203, 1204, 1205 and the copper foil 103 on which a pattern which is a component of the multilayer substrate is formed are arranged in layers, and are heated under the resin curing temperature. When the laminate press is performed, the resin in the prepreg is cured, and a six-layer substrate 13 having a cross-sectional shape (by the penetration method) as shown in FIG. 17 is obtained, and the Tg of the substrate is about 200 ° C. As a result, a multilayer board having the original characteristics of the material can be obtained.
[0005]
However, the resin-coated copper foil 12 made by peeling the resist film 11 after circuit formation is corroded by the solvent before the reaction by a solvent such as alkali used at the time of peeling, and does not react sufficiently after curing. There is a problem that the adhesive strength deteriorates. In particular, there is a drop test on a substrate for a mobile product such as a mobile phone, and the adhesive strength of this resin is important. However, in the lapping-type single press method using the resist film, the insulating materials of each layer are in close contact with each other. There is a problem that the adhesive corrodes. The present invention has been made to solve the above conventional problems. That is, the present invention provides a method for producing a printed wiring board having high interlayer connection reliability and high mechanical strength without complicating the production process. Law Lint wiring base Board The purpose is to provide.
[0006]
[Means for Solving the Problems]
The printed wiring board manufacturing method of the present invention includes a step of forming a plurality of substantially conical conductor bumps on a conductor plate, a step of setting an uncured insulating material substrate on the conductor bumps, and the insulating material substrate. Pressurizing the conductive plate and the insulating material substrate through a buffer material while heating at a temperature at which the conductive bump does not cure, and passing the conductive bump through the insulating material substrate; and the conductive bump and the insulating material substrate Heating hard A step of forming a single-layer wiring board having a predetermined wiring pattern by patterning the conductive plate, and the single layer Insulating material substrate surface after heat curing on wiring board Alternatively, a step of forming a substrate unit by applying an adhesive to the wiring pattern surface, a step of stacking a plurality of substrate units to form a multilayer plate precursor, and pressurizing the multilayer plate precursor under heating to A step of connecting the conductor bump and the wiring pattern and curing the adhesive layer.
[0007]
Another printed wiring board manufacturing method of the present invention includes a step of forming a plurality of substantially conical conductor bumps on a first conductor plate, and a step of setting an uncured insulating material substrate on the conductor bumps. A step of pressing the first conductive plate and the insulating material substrate through a buffer while heating the insulating material substrate at a temperature at which the insulating material substrate is not cured, and passing the conductive bump through the insulating material substrate; The conductor bump and the insulating material substrate are formed by laminating a second conductor plate and a second buffer material on the penetrating insulating substrate and pressurizing under heating. Heating hard A step of patterning the conductive plate to form a single-layer wiring board having a predetermined wiring pattern, a step of removing the second conductive plate by etching, and the single layer Insulating material substrate surface after heat curing on wiring board Alternatively, a step of forming a substrate unit by applying an adhesive to the wiring pattern surface, a step of stacking a plurality of substrate units to form a multilayer plate precursor, and pressurizing the multilayer plate precursor under heating to A step of connecting the conductor bump and the wiring pattern and curing the adhesive layer.
[0008]
In the method for manufacturing a printed wiring board, as a step of penetrating the conductor bumps through the insulating material substrate, the tip of the conductor bumps is planarized and deformed so that the average top surface diameter is 50% or more of the bottom surface diameter. The process to make can be mentioned. In the method for manufacturing a printed wiring board, the step of causing the conductor bumps to penetrate the insulating material substrate includes a step of deforming so that the upper surface of the conductor bump protrudes from the insulating material substrate surface by 5 to 20 μm. Can do.
[0009]
Still another printed wiring board manufacturing method of the present invention includes a step of forming a plurality of substantially conical conductor bumps on a conductor plate, a step of setting an uncured insulating material substrate on the conductor bumps, A step of pressing the conductor plate and the insulating material substrate through a buffering material while heating at a temperature at which the insulating material substrate is not cured, and passing the conductor bumps through the insulating material substrate; and the conductor bump and the insulating material substrate Heating hard A step of forming a single-layer wiring board having a predetermined wiring pattern by patterning the conductive plate, and the single layer Insulating material substrate surface after heat curing on wiring board Alternatively, a step of applying an adhesive to the wiring pattern surface to form a substrate unit, and a wiring pattern on the first surface and the second surface of the cured insulating material substrate, respectively, the first surface and the second surface A multilayer wiring board in which a core material containing an electrical interlayer connection member for electrically connecting wiring patterns formed on the surface is formed; and at least one board unit is laminated on both surfaces of the core material. A step of forming a precursor, and a step of pressurizing the multilayer wiring board precursor under heating to interconnect the wiring patterns and simultaneously cure the adhesive layer.
[0010]
In the printed wiring board manufacturing method, as the step of forming the core material, a step of forming a substantially conical conductor bump on the first conductor plate, and an uncured insulating material on the tip side of the conductor bump A step of disposing a substrate, a step of pressurizing the first conductive plate and the insulating material substrate to cause the conductive bumps to penetrate the insulating material substrate, and the insulating material substrate through which the tips of the conductive bumps penetrated A step of setting a second conductor plate on the surface, a step of curing the insulating material substrate by pressurizing the first conductor plate and the second conductor plate under heating, and the first conductor plate And a step of forming a pattern on the second conductor plate.
[0011]
In the printed wiring board manufacturing method, the core material may be a copper plated through-hole board.
[0012]
In the printed wiring board manufacturing method, as the step of forming the substrate unit, a step of applying the adhesive onto the mating wiring pattern that abuts the tip of the conductor bump can be exemplified.
[0013]
In the method for manufacturing a printed wiring board, examples of the adhesive include the same resin as the resin impregnated in the reinforcing material of the insulating material board, or a resin whose viscosity is reduced.
[0014]
The printed wiring board of the present invention includes a plurality of insulating layers, an interlayer wiring layer disposed between the insulating layers and the insulating layer, and a plurality of surface wiring layers disposed on the surface of the outermost insulating layer. And an interlayer connection member that is disposed in the insulating layer and connects the interlayer wiring layers facing each other through the insulating layer, and is disposed in the outermost insulating layer, and a front end side is disposed on the surface wiring layer. Conductive bumps that abut An adhesive layer obtained by applying an adhesive to the surface of the insulating layer or the interlayer wiring layer after heat-curing the conductive bump group and the insulating layer, and then curing the adhesive; It comprises.
[0015]
In the printed wiring board, the insulating layer Is a supplement Hardened adhesive without strong material Including the adhesive layer, and the adhesive layer, Reinforcement layer reinforced with a reinforcement sheet inside the fat And It may be a laminate.
[0017]
In the printed wiring manufacturing method of the present invention, the insulating material substrate and the conductor bump are completely cured for each single-layer wiring board, and then laminated on the core material through the adhesive layer to form a multilayer board precursor. Since the adhesive layer is cured by heating and pressurizing as a whole of the multilayer plate precursor, the number of lamination presses is reduced from 3 to 2 in the conventional method when a 6-layer substrate is manufactured. Thereby, the heat history by the press of the insulating material board | substrate of all the layers reduces. In addition, since the adhesive is applied to the single-layer wiring board, the adhesion between the insulating material substrates is improved, and voids and swelling are less likely to occur due to the temperature load applied during solder reflow. Metal migration is less likely to occur. Moreover, the positional deviation resulting from the difference in the heat shrinkage rate at the time of the lamination press is reduced. Furthermore, in the case of a 6-layer substrate, the number of lamination presses is reduced to 2/3, so that the cost can be greatly reduced. When this method is applied to a high multi-layer board having a larger number of stacked layers, the reliability is improved and the added value is increased as compared with the conventional multi-layer board.
[0018]
When the step of penetrating the conductor bump into the insulating material substrate is a step of flattening the tip of the conductor bump and deforming it so that the average top surface diameter is 50% or more of the bottom surface diameter, By flattening, the contact area with the wiring pattern to be brought into contact increases, and the resistance value at the contact surface decreases. Further, by flattening the tips of the conductor bumps, the conductor bumps can be sufficiently compressed even if the pressure during the lamination press is small, and the substrate units can be stacked and pressed at once in multiple stages.
[0019]
When the step of penetrating the conductive bump into the insulating material substrate is a step of deforming the conductive bump so that the upper surface of the conductive bump protrudes 5 to 20 μm from the insulating material substrate surface, the upper surface of the conductive bump is the insulating material substrate. By projecting 5 to 20 μm, the conductive bumps easily penetrate the adhesive layer at the time of laminating press, the contact area with the wiring pattern to be brought into contact is increased, the connection resistance is lowered, and a reliable interlayer connection is formed. .
[0020]
At least one board unit is laminated on both sides of the core material to form a multilayer wiring board precursor, and the multilayer wiring board precursor is pressed under heating to connect the wiring patterns to each other at the same time. When the adhesive layer is cured, the conductor bumps are abutted against the core material, so that the substantially conical shape of the conductor bumps has a vertically symmetric structure around the core substrate (core material). Reliability is improved against heat load.
[0021]
A core material manufactured by the penetration method is used as the core material of the multilayer board, and a substrate unit is laminated on the core material to form a multilayer wiring board precursor, and the multilayer wiring board precursor is pressurized under heating. When the printed wiring board is manufactured by curing the adhesive layer, the core material by the penetration method is as thin as about 0.1 mm as in the case of the single-layer wiring board, so the overall thickness of the multilayer board is made small. And can meet current market demands as well as future high integration demands.
[0022]
When a through-hole substrate made of copper plating is used as the core material as the core material, the core material is a through-hole substrate made of copper plating. A layer substrate can be made, and the way to make it is flexible. Moreover, since a core material with a large plate thickness can be made with a through-hole substrate, the plate thickness of the entire multilayer board can be increased.
[0023]
When the same resin as the resin impregnated in the reinforcing material of the insulating material substrate is used as the adhesive, or when the viscosity of the resin is decreased, the adhesive and the prepreg are familiar, so It is easy to form, and after the insulating material substrates of the respective layers are integrated by the lamination press, they can be prevented from being deteriorated due to corrosion and peeling from the joint surfaces of different materials.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
A method for manufacturing a printed wiring board according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a flowchart of a method for manufacturing a printed wiring board according to the present embodiment, and FIGS. 2 to 4 are cross-sectional views schematically showing a manufacturing process of the printed wiring board according to the present embodiment. In order to manufacture the printed wiring board according to the present embodiment, first, for example, a silver paste is printed on a copper foil 1 having a thickness of 18 μm, for example, as shown in FIG. Conical conductor bumps 2, 2,... Are formed (step 1). Next, as shown in FIG. 2B, a BT resin material (Mitsubishi Gas Chemical Co., Ltd., model name: GHPL830, thickness 0.06 mm) in which a glass cloth is impregnated with an epoxy resin is used as an insulating material substrate prepreg 3, and copper This insulating material substrate prepreg 3 is set in a predetermined position on the side of the foil 1 where the conductor bumps 2, 2,... Are formed (step 2), and these are placed at 115 to 135 ° C. via an elastic material (not shown). Then, pressure is applied under heating (step 3), and the conductor bumps 2, 2,... Are penetrated in the thickness direction of the insulating material substrate prepreg 3 to form the resin-coated copper foil 4. (The process up to this point is the same as that shown in FIGS. 12 (a) to 12 (c) and FIGS. 15 (a) to 15 (c)). As shown in c), the tips of the substantially conical conductor bumps 2, 2,. At this time, the insulating material prepreg 3 is in an uncured so-called B stage state.
[0026]
Next, as shown in FIG. 2D, a buffer material 14 made of an organic material having a thickness of 0.1 mm is stacked on the side of the conductor bump of the resin-coated copper foil 4 whose tip is flattened (step 4). When pressure is applied under heating at 190 ° C. for 2 hours (step 5), as shown in FIG. 2 (e), the cushioning material 1402 is deformed and integrated by the conductor bumps 2, 2,. The insulating material substrate prepreg 3 and the conductor bumps 2, 2,... At this time are completely cured. When this is selectively exposed and developed (not shown) and the copper foil 1 is etched and patterned (step 6), the one shown in FIG. 2 (f) is obtained. Next, when the buffer material 1402 made of an organic material having a thickness of 0.1 mm is peeled off (step 7), the single-layer wiring board 16 having the wiring pattern as shown in FIG. 2G is formed.
[0027]
Next, a liquid epoxy adhesive 17 such as bismaleidotriazine resin is applied to the entire surface of the insulating material substrate on the protruding side of the conductor bumps 2, 2,... Of the single-layer wiring board 16 on which the wiring pattern is formed (step 8). The substrate unit 18 is formed.
[0028]
Next, a plurality of board units 1801 to 1805 similar to the board unit 18, a copper foil 104 having a thickness of 18 μm, and board units 1801, 1802, 1803, 1804, and 1805 are stacked as shown in FIG. ), When a lamination press is performed under heating at 190 ° C. for 2 hours (step 10), the applied adhesive is cured and the substrate units 1801, 1802, 1803, 1804, 1805 are joined, and the conductor bump 2, 2 are six layers in which the number of times of laminating press is two times by the penetration method in which the respective layers as shown in FIG. 4 that penetrate through the adhesive and are connected to the copper foil 104 are electrically connected by the conductor bumps 2, 2,. The printed wiring board 19 is obtained.
[0029]
As the applied liquid adhesive is cured, the adhesion between the insulating material substrates in the multilayer substrate is improved compared to the single press method of the prior art. In addition, the migration resistance of the test applying voltage at high temperature and high humidity was improved. This method is very effective as a next-generation printed wiring board manufacturing method in which the number of lamination steps is increased because the total number of laminations is two regardless of the number of layers of the multilayer substrate.
[0030]
(Second Embodiment)
A method for manufacturing a printed wiring board according to the second embodiment of the present invention will be described with reference to FIGS. 2, 4, 5, and 6. FIG. 5 is a flowchart showing a flow of a method for manufacturing a printed wiring board according to the present embodiment. To manufacture the printed wiring board according to the present embodiment, first, as in the first embodiment, as shown in FIG. 2C through FIG. 2A and FIG. 2B. The resin-coated copper foil 4 having a flat front end of the conductor bump is formed (steps 1 to 3). At this time, the insulating material is in an uncured B stage state. Next, a copper foil 20 having a thickness of 9 μm and a kraft paper (not shown) having a thickness of 0.5 mm are placed thereon as a cushioning material as shown in FIG. (Step 4). Next, when pressure is applied under heating at about 190 ° C. for 2 hours in this state (step 5), the copper foil is pressure-deformed by the conductor bump 2 as in 2002 as shown in FIG. At this time, the insulating material substrate and the conductor bumps 2, 2,... Are completely cured. A single-layer wiring board on which a wiring pattern as shown in FIG. 2G is formed by selectively performing exposure and development (not shown), etching the copper foil, and patterning (step 6). 16 is formed.
[0031]
Thereafter, in the same manner as in the first embodiment, the buffer material 1402 is peeled off (step 7), a liquid adhesive is applied (step 8), the substrate units are stacked and arranged (step 9), and a lamination press is performed. (Step 10), a six-layer printed wiring board 19 is obtained in which the respective layers are electrically connected by conductor bumps 2, 2,...
[0032]
(Third embodiment)
A method for manufacturing a printed wiring board according to the third embodiment of the present invention will be described with reference to FIGS. 12, 2, 4, 7, and 8. FIG. 7 is a flowchart showing a flow of a method for manufacturing a printed wiring board according to the present embodiment. In order to manufacture the printed wiring board according to the present embodiment, first, as shown in FIG. 12A, a conductive paste is printed on a copper foil 1 having a thickness of 18 μm to form a substantially conical conductor bump having a diameter of 0.2 mm. 2, 2,... (Step 1 a), and then an insulating material substrate prepreg 3 made of a BT resin material impregnated with an epoxy resin, for example, is laminated on a glass cloth as shown in FIG. The conductor bumps 2, 2,... Are penetrated in the thickness direction to create a resin-attached copper foil 4 as shown in FIG. 12C (step 3a), and the resin-attached copper foil 4 shown in FIG. Then, another copper foil 102 having a thickness of 18 μm is overlaid (step 4a), and a lamination press is performed by heating and heating at 190 ° C. for 2 hours (step 5a), and double-sided copper-clad as shown in FIG. A plate 502 is prepared and then patterned (step By performing step 6a), a double-sided substrate 602 by a penetration method as shown in FIG.
[0033]
Next, the double-sided substrate 602 formed by the penetration method is used as a core material, and the substrate unit 18 manufactured as shown in FIG. 2 in the first embodiment is laminated as shown in 1806, 1807, 1808, and 1809 in FIG. When placed and laminated (step 7a) and subjected to a laminating press that pressurizes with heating at 190 ° C. for 2 hours (step 8a), the applied adhesive is cured to bond the insulating material substrates of the respective layers, and the conductor bumps 2, 2, .. Penetrates through the adhesive to obtain a six-layer printed wiring board 21 by a penetration method in which the respective layers are electrically connected by conductor bumps 2, 2,... In this substrate, as compared with the six-layer substrate 19 of the first embodiment shown in FIG. 4, the structure of the conductor bumps 2, 2,. Therefore, it has a very stable structure that is strong against the heat load during the laminating press.
[0034]
(Fourth embodiment)
A fourth embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 9, a double-sided substrate 602 by a penetration method is used as a core material, a liquid epoxy adhesive 17 is applied to the surface, and a wiring pattern prepared as shown in FIG. The single-layer wiring board 16 is laminated and disposed as shown by 1601, 1602, 1603, and 1604 in FIG. 9, and a liquid epoxy adhesive 17 (BT resin) is applied on the copper foils 1602 and 1603 in advance. As shown in FIG. 8B, a six-layer printed wiring board 21 can be obtained by a penetration method in which the respective layers are electrically connected by conductor bumps 2, 2,.
[0035]
(Fifth embodiment)
A printed wiring board manufacturing method according to the fifth embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the core material by the penetration method used for manufacturing the double-sided substrate 6 in the third embodiment, the core material by the normal copper plating through-hole method as shown in FIG. The multilayer printed wiring board 23 as shown in FIG. 10B is formed by using the board 22 and butting the board unit 18 created in the first embodiment to the outside. In this case, when a substrate having a large thickness is selected as the core material 22, the thickness of the finished multilayer printed wiring board 23 can be increased, and a specific effect can be obtained that the thickness of the substrate can be freely controlled.
[0036]
(Sixth Embodiment) In this embodiment, the semiconductor device 30 is formed by using the six-layer printed wiring board 19 manufactured in the first embodiment. FIG. 11 is a cross-sectional view of the semiconductor device 30 according to the present embodiment. In the semiconductor device 30 according to the present embodiment, first, the six-layer printed wiring board 19 manufactured in the first embodiment is prepared, and the copper foils on both sides of the printed wiring board 19 are subjected to, for example, etching treatment to form a wiring pattern. 1a and 1f are formed. At this time, the direction of the printed wiring board 19 is such that the outermost conductor bump 201 faces the tip side upward and the cross section becomes a regular trapezoid. On the other hand, the outer side conductor bump 205 on the opposite side is also made to have a trapezoidal cross section with the tip side facing upward.
[0037]
That is, the wiring pattern 1 a is formed on the uppermost part of the printed wiring board 19 and is electrically connected to the front end side of the conductor bump 201. On the other hand, the wiring pattern 1 f is formed at the lowermost portion and is electrically connected to the bottom surface side of the conductor bump 205. An anisotropic conductive resin 25 and gold ball bumps 27 are disposed on the wiring pattern 1a, and a bare chip type IC chip 24 is disposed thereon as a semiconductor element. The IC electrode 28 of the IC chip 24 is electrically connected to the wiring pattern 1 a via the gold ball bump 27. Here, since the wiring pattern 1a is connected to the tip side of the conductor bump 201, each line width of the wiring pattern 1a can be reduced. For example, in the semiconductor device 30, the wiring pattern 1a is formed with a line width of about 0.3 mm. As described above, in the present embodiment, since the conductor bump 201 immediately below the mounting surface is arranged in the direction in which the tip is directed to the mounting surface side, the minimum line width of the wiring pattern 1a can be reduced, The degree of integration of wiring patterns can be increased.
[0038]
On the other hand, the wiring pattern 1f is formed with a line width of about 0.4 mm. The wiring pattern 1f is electrically connected to the bottom surface side of the conductor bump 205, and the contact area between the wiring pattern 1f and the conductor bump 205 is large and is securely connected. Therefore, when the solder ball 26 is disposed on the wiring pattern 1 f as shown in FIG. 11B, the wiring pattern 1 f highly resistant to thermal shock and the bottom surface side of the conductor bump 205 are close to the solder ball 26. Therefore, even when the semiconductor device 30 is mounted on a mother board (not shown), the separation between the wiring pattern 1f and the conductor bump 205 hardly occurs, and a specific effect that a highly reliable semiconductor device can be obtained. Is obtained.
[0039]
【The invention's effect】
In the printed wiring manufacturing method of the present invention, the insulating material substrate and the conductor bump are completely cured for each single-layer wiring board, and then laminated on the core material through the adhesive layer to form a multilayer board precursor. Since the adhesive layer is cured by heating and pressurizing as a whole of the multilayer plate precursor, the number of lamination presses is reduced from 3 to 2 in the conventional method when a 6-layer substrate is manufactured. Thereby, the heat history by the press of the insulating material board | substrate of all the layers reduces. In addition, since the adhesive is applied to the single-layer wiring board, the adhesion between the insulating material substrates is improved, and voids and swelling are less likely to occur due to the temperature load applied during solder reflow. Metal migration is less likely to occur. Moreover, the positional deviation resulting from the difference in the heat shrinkage rate at the time of the lamination press is reduced. Furthermore, in the case of a 6-layer substrate, the number of lamination presses is reduced to 2/3, so that the cost can be greatly reduced. When this method is applied to a high multi-layer board having a larger number of stacked layers, the reliability is improved and the added value is increased as compared with the conventional multi-layer board.
[0040]
When the step of penetrating the conductor bump into the insulating material substrate is a step of flattening the tip of the conductor bump and deforming it so that the average top surface diameter is 50% or more of the bottom surface diameter, By flattening, the contact area with the wiring pattern to be brought into contact increases, and the resistance value at the contact surface decreases. Further, by flattening the tips of the conductor bumps, the conductor bumps can be sufficiently compressed even if the pressure during the lamination press is small, and the substrate units can be stacked and pressed at once in multiple stages.
[0041]
When the step of penetrating the conductive bump into the insulating material substrate is a step of deforming the conductive bump so that the upper surface of the conductive bump protrudes 5 to 20 μm from the insulating material substrate surface, the upper surface of the conductive bump is the insulating material substrate. By projecting 5 to 20 μm, the conductive bumps easily penetrate the adhesive layer at the time of laminating press, the contact area with the wiring pattern to be brought into contact is increased, the connection resistance is lowered, and a reliable interlayer connection is formed. .
[0042]
At least one board unit is laminated on both sides of the core material to form a multilayer wiring board precursor, and the multilayer wiring board precursor is pressed under heating to connect the wiring patterns to each other at the same time. When the adhesive layer is cured, the conductor bumps are abutted against the core material, so that the substantially conical shape of the conductor bumps has a vertically symmetric structure around the core substrate (core material). Reliability is improved against heat load.
[0043]
A core material manufactured by the penetration method is used as the core material of the multilayer board, and a substrate unit is laminated on the core material to form a multilayer wiring board precursor, and the multilayer wiring board precursor is pressurized under heating. When the printed wiring board is manufactured by curing the adhesive layer, the core material by the penetration method is as thin as about 0.1 mm as in the case of the single-layer wiring board, so the overall thickness of the multilayer board is made small. And can meet current market demands as well as future high integration demands.
[0044]
When a through-hole substrate made of copper plating is used as the core material as the core material, the core material is a through-hole substrate made of copper plating. A layer substrate can be made, and the way to make it is flexible. Moreover, since a core material with a large plate thickness can be made with a through-hole substrate, the plate thickness of the entire multilayer board can be increased.
[0045]
When the same resin as the resin impregnated in the reinforcing material of the insulating material substrate is used as the adhesive, or when the viscosity of the resin is decreased, the adhesive and the prepreg are familiar, so It is easy to form, and after the insulating material substrates of the respective layers are integrated by the lamination press, they can be prevented from being deteriorated due to corrosion and peeling from the joint surfaces of different materials.
[0046]
In the printed wiring board of the present invention, the outermost insulating layer of the multilayer board is disposed in the thickness direction, the surface wiring layer disposed on the outermost insulating layer, and the outermost insulating layer. Since the conductor bumps connecting the wiring layers disposed on the inner side to each other are arranged in such a direction that the front end side comes into contact with the surface wiring layer, the wiring pattern width of the surface wiring layer can be reduced. Therefore, the wiring pattern on the surface of the multilayer board can be finely patterned, and the degree of integration can be improved. In addition, a semiconductor device having a fine wiring pattern can be obtained by mounting a semiconductor element or the like on the surface wiring layer of the multilayer board on which such a fine pattern is formed.
[Brief description of the drawings]
FIG. 1 is a flowchart of a method for manufacturing a printed wiring board according to a first embodiment.
FIG. 2 is a cross-sectional view of the printed wiring board according to the first embodiment in the course of manufacturing, showing the process up to the production of a substrate unit coated with a liquid epoxy adhesive (BT resin).
FIG. 3 is a cross-sectional view of the printed wiring board according to the first embodiment in the middle of manufacture, showing a state in which board units are stacked and arranged.
FIG. 4 is a cross-sectional view of the printed wiring board according to the first embodiment in the middle of manufacture, showing a cross-section of a six-layer board formed by performing a lamination press twice by a penetration method.
FIG. 5 is a flowchart of a method for manufacturing a printed wiring board according to a second embodiment.
FIG. 6 is a cross-sectional view of the printed wiring board according to the second embodiment in the course of manufacturing, and is a cross-sectional view illustrating a method of manufacturing a board unit using a conductor plate and a buffer material.
FIG. 7 is a flowchart of a method for manufacturing a printed wiring board according to a third embodiment.
FIG. 8 is a cross-sectional view of the printed wiring board according to the third embodiment in the middle of manufacture, and is a lamination method by a penetration method in a state (a) in which a substrate unit is laminated by using a double-sided substrate by a penetration method as a core material; It is sectional drawing (b) of the 6-layer board | substrate formed by pressing twice.
FIG. 9 is a cross-sectional view of a printed wiring board according to a fourth embodiment in the course of manufacturing, and is a cross-sectional view in which an adhesive is applied to a conductor bump abutting counterpart and stacked.
FIG. 10 is a cross-sectional view in the middle of manufacturing a printed wiring board according to a fifth embodiment, and is a cross-sectional view illustrating a manufacturing process of a multilayer substrate using a through-hole substrate as a core material.
FIG. 11 is a cross-sectional view of a semiconductor device according to a sixth embodiment.
FIG. 12 is a cross-sectional view showing a process until a double-sided substrate is manufactured by a conventional penetration method.
FIG. 13 is a cross-sectional view showing a process until a four-layer substrate is manufactured by a conventional penetration method.
FIG. 14 is a cross-sectional view showing steps up to the fabrication of a six-layer substrate by a conventional penetration method.
FIG. 15 is a cross-sectional view showing an improved example of a conventional penetration method.
FIG. 16 is a cross-sectional view showing an improved example of a conventional penetration method, and shows a state in which a copper foil with an insulating material substrate on which a pattern is formed is laminated.
FIG. 17 is a view showing an improved example of the conventional penetration method, and is a cross-sectional view of a six-layer substrate formed by performing a laminating press by the penetration method once.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Copper foil, 2 ... Conductor bump, 3 ... Insulation material board | substrate, 4 ... Resin-coated copper foil, 502 ... Double-sided copper-clad board, 602 ... Double-sided board | substrate (by the penetration method), 702 ... (By the penetration method) 4 layer board | substrate 8 ... (by penetration method) 6-layer substrate, 9 ... via, 11 ... resist film, 12 ... copper foil with insulating material substrate, 13 ... 6-layer substrate, 14 ... buffer material, 1402 ... deformed buffer material, 16 ... Single layer wiring board, 17 ... Liquid epoxy adhesive (BT resin), 18 ... Substrate unit, 19 ... 6 layer substrate, 20 ... Copper foil, 2002 ... Deformed copper foil, 21 ... 6 layer substrate, 22 ... Core substrate ( Core material), 23 ... multilayer printed wiring board.

Claims (11)

Forming a plurality of substantially conical conductor bumps on the conductor plate;
Setting an uncured insulating material substrate on the conductor bumps;
Pressing the conductor plate and the insulating material substrate through a buffer material while heating at a temperature at which the insulating material substrate is not cured, and penetrating the conductor bumps through the insulating material substrate;
A step of heating the hardness of the conductive bump and the insulating material substrate,
Patterning the conductor plate to form a single-layer wiring board having a predetermined wiring pattern;
Forming a substrate unit by applying an adhesive to the surface of the insulating material substrate or the wiring pattern surface after heat curing in the single-layer wiring board ;
Laminating a plurality of substrate units to form a multilayer plate precursor;
A method of manufacturing a printed wiring board comprising: pressurizing the multilayer board precursor under heating to connect the conductor bumps and the wiring pattern and curing the adhesive layer. Forming a plurality of substantially conical conductor bumps on the first conductor plate;
Setting an uncured insulating material substrate on the conductor bumps;
Pressing the first conductor plate and the insulating material substrate through a buffer material while heating at a temperature at which the insulating material substrate does not cure, and penetrating the conductor bumps through the insulating material substrate;
A step of heating the hardness of the second conductive plate and a second of said cushioning material is pressurized under heating by laminating conductor bumps and the insulating material substrate to the conductor bump penetrates the insulating substrate,
Patterning the conductor plate to form a single-layer wiring board having a predetermined wiring pattern;
Removing the second conductor plate by etching;
Forming a substrate unit by applying an adhesive to the surface of the insulating material substrate or the wiring pattern surface after heat curing in the single-layer wiring board ;
Laminating a plurality of substrate units to form a multilayer plate precursor;
A method of manufacturing a printed wiring board comprising: pressurizing the multilayer board precursor under heating to connect the conductor bumps and the wiring pattern and curing the adhesive layer.   3. The method for manufacturing a printed wiring board according to claim 1, wherein the step of penetrating the conductor bumps through the insulating material substrate planarizes the tips of the conductor bumps, and the top surface diameter is the bottom surface diameter on average. A process for producing a printed wiring board, which is a step of deforming to 50% or more of   It is a manufacturing method of the printed wiring board of any one of Claims 1-3, Comprising: The process which penetrates the said conductor bump to the said insulating material board | substrate WHEREIN: The upper surface of the said conductor bump is 5 from an insulating material board | substrate surface. A method of manufacturing a printed wiring board, which is a step of deforming to have a structure protruding 20 μm. Forming a plurality of substantially conical conductor bumps on the conductor plate;
Setting an uncured insulating material substrate on the conductor bumps;
Pressing the conductor plate and the insulating material substrate through a buffer material while heating at a temperature at which the insulating material substrate is not cured, and penetrating the conductor bumps through the insulating material substrate;
A step of heating the hardness of the conductive bump and the insulating material substrate,
Patterning the conductor plate to form a single-layer wiring board having a predetermined wiring pattern;
Forming a substrate unit by applying an adhesive to the surface of the insulating material substrate or the wiring pattern surface after heat curing in the single-layer wiring board ;
An electrical interlayer connecting member provided with a wiring pattern on each of the first surface and the second surface of the cured insulating material substrate and electrically connecting the wiring patterns formed on the first surface and the second surface; Forming a core material to be embedded;
Forming a multilayer wiring board precursor by laminating and arranging at least one board unit on both sides of the core material;
A step of pressurizing the multilayer wiring board precursor under heating to interconnect each wiring pattern and simultaneously curing the adhesive layer. It is a manufacturing method of the printed wiring board according to claim 5, A process of forming the core material,
Forming a substantially conical conductor bump on the first conductor plate;
Disposing an uncured insulating material substrate on the leading end side of the conductor bump;
Pressurizing the first conductive plate and the insulating material substrate to penetrate the conductive bumps through the insulating material substrate;
Setting a second conductor plate on the surface of the insulating material substrate through which the tip of the conductor bump penetrated;
Pressurizing the first conductor plate and the second conductor plate under heating to cure the insulating material substrate; forming a pattern on the first conductor plate and the second conductor plate;
A process for producing a printed wiring board, comprising:   6. The method for manufacturing a printed wiring board according to claim 5, wherein the core material is a copper-plated through-hole board.   It is a manufacturing method of the printed wiring board of any one of Claims 1-7, Comprising: The process of forming the said board | substrate unit places the said adhesive agent on the wiring pattern of the other party which abuts the said conductor bump front-end | tip. A method for producing a printed wiring board, which is a coating step.   It is a manufacturing method of the printed wiring board of any one of Claims 1-8, Comprising: The said resin is the same resin as the resin which the reinforcing material of the said insulating material board was impregnated, or the viscosity of the said resin A method of manufacturing a printed wiring board, wherein the printed circuit board is reduced. A plurality of insulating layers;
An interlayer wiring layer disposed between the insulating layer and the insulating layer;
A plurality of surface wiring layers disposed on the surface of the outermost insulating layer;
An interlayer connecting member disposed in the insulating layer and connecting the interlayer wiring layers facing each other through the insulating layer;
A conductor bump group disposed in the outermost insulating layer and having a front end abutting against the surface wiring layer;
Applying an adhesive to the surface of the insulating layer or the interlayer wiring layer after heat-curing the conductor bump group and the insulating layer, and then an adhesive layer obtained by curing the adhesive;
A printed wiring board comprising: A printed wiring board according to claim 10, wherein the insulating layer includes the adhesive layer formed by curing the adhesive containing no reinforcement material, and the adhesive layer, a reinforcing sheet internal tree fat in the printed circuit board, characterized in that the reinforcement layer reinforced, which is a laminate.

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