JP2005109188A - Circuit board and multilayer board, and method for manufacturing circuit board and multilayer board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable and highly productive multilayer board having only a few variation in height, area, and shape, and capable of surely achieving an interlayer connection. <P>SOLUTION: A circuit board has an insulating base material, a conductor circuit formed on one side of the insulating base material, and a conductor post formed on the other side by etching. The conductor circuit and the conductor post are electrically connected by a field via, and the conductor post is covered by a metal plating layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a circuit board, a multilayer board, a circuit board manufacturing method, and a multilayer board manufacturing method, and more particularly to a multilayer printed wiring board used as a component of an electronic device, a circuit board constituting the same, and a manufacturing method thereof. It is.

With the recent development of electronic devices such as mobile terminals, there is an increasing demand for higher functionality, smaller size, and lighter weight. With this, printed wiring boards are also required to have higher density wiring and higher multilayers. Is growing. In particular, in order to satisfy the demand for mounting high-density components on a wiring board, a structure that eliminates restrictions on wiring as much as possible is required, and IVH, which is an interlayer connection method, is an important factor.
In conventional through-through hole connection in mass lamination and IVH connection in build-up lamination, a wiring pattern or IVH cannot be formed on IVH, and therefore there is an increasing demand for filled vias capable of a stacked via structure.

The following method has been proposed for the multilayer stack having such a stacked via structure.
(1) The inside of IVH is filled with a conductor paste, and another conductor layer is laminated thereon.
(2) A conductor post is formed by printing or the like, penetrates through the insulating layer, and is pressed into contact with another conductor layer.
(3) After conducting conductive connection and electroplating on the inner wall of the IVH, it is filled with an insulating material called a hole filling material, and a conductor layer is formed on the surface layer.
(4) After conducting the IVH on the entire surface layer of the substrate, the entire surface is electrolytically plated, so that the surface layer of the substrate and the IVH are filled so as to be uniform.
(5) An insulating layer or a resist layer is formed on the conductor layer to form IVH, and then a conductor post is formed by electroplating.

The multilayer processing method using such filled vias has the following problems.
The above (1) is a method of obtaining a multilayer printed wiring board by batch lamination after forming IVH on a special material called organic unclothed cloth, filling with a conductive paste (for example, Patent Document 1). In this method, a wet process is not required and a multi-layer wiring board can be obtained with less man-hours. However, since IVH is filled with a conductive paste, it is difficult to reduce the diameter of IVH and to increase the density.

  The above (2) is a build-up method in which a sharp needle-shaped metal post is formed on the conductor layer by a special printing method, and the insulating resin for lamination is penetrated by hot pressure and then pressed to the conductor layer (for example, Patent Document 2). This method is characterized in that a wet process is not required and the material is not relatively limited. However, similarly to the above (1), it is difficult to reduce the diameter of IVH because of the manufacturing method, and it is difficult to increase the density.

  The above (3) is an application of the conventional mass method or build-up method, and there is a problem that the steps such as filling the insulating material and forming the surface conductor layer increase.

  The above (4) is an application of a circuit formation method developed in the semiconductor package field or the like. After making the entire surface layer including IVH into a conductor, promote the plating on the bottom of the IVH and suppress the plating on the surface layer by electrolytic copper plating at the same time, fill the inside of the IVH with the plating to the plating height of the surface layer, and flatten it Filled beer method. In this method, the burden of the copper plating solution is large, the solution life is short, and severe control is required for the additive.

  The above four processing methods are mainly used in the build-up method, and as the number of layers increases, the number of processes increases and there are problems in man-hours and management.

In (5) above, a resist layer is laminated on the conductor layer to form IVH. Or after forming IVH in the insulating layer used as the support base material of a printed wiring board, the inside of IVH is filled with a conductor by electroplating, and a conductor post is formed.
This is a method of laminating these conductor posts by soldering with conductor layers of other wiring boards (for example, Patent Document 3). This method has been attracting attention in recent years due to the reduction in diameter and high reliability by plating and the rationalization of processes by batch lamination. However, the formation of conductor posts by electroplating is easily affected by the current distribution, and for high-density mounting boards that require post height accuracy, it is necessary to plate at a lower current, and the conductor extends to several tens of μm. There is a problem in productivity because the post formation requires a long time. Furthermore, the conductor post deposited by plating also has problems of surface smoothness and plating roughness and post shape restriction.
JP-A-8-316598 JP-A-8-195560 JP-A-10-288924

  In order to solve the above problems, the present invention provides a circuit board, a multilayer board, a method of manufacturing a circuit board, and a circuit board that can easily and reliably achieve interlayer connection and can stack highly reliable outer layer wiring boards. A method for manufacturing a multilayer substrate is provided.

Such an object is achieved by the present invention described in the following (1) to (19).
(1) It has an insulating substrate, a conductor circuit formed on one surface side of the insulating substrate, and a conductor post formed by etching on the other surface side, and the conductor circuit and the conductor post Are electrically connected by filled vias, and the conductor posts are covered with a metal coating layer.
(2) The metal coating layer is composed of at least one metal selected from the group consisting of gold, silver, nickel, tin, lead, zinc, bismuth, antimony, indium, and copper, or an alloy containing the metal. The circuit board according to (1).
(3) The circuit board according to (1) or (2) above, wherein an adhesive layer having a flux function is provided on one or both surfaces of the insulating base.
(4) A multilayer board comprising a plurality of circuit boards including the circuit board according to any one of (1) to (3) above.
(5) A plurality of circuit boards including an insulating base, a circuit board having conductor circuits formed on both surfaces of the insulating base, and the circuit board according to any one of (1) to (3) above A multilayer substrate characterized by being laminated.
(6) An insulating base material, a circuit board having a conductor circuit formed on both surfaces of the insulating base material, and the circuit board according to any one of the above (1) to (3) are joined, A multilayer board characterized in that a predetermined portion of a conductor circuit of each circuit board is electrically connected through a conductor post.
(7) forming a through hole in the insulating base material in which a metal layer serving as a conductor circuit is formed on both surfaces of the insulating base material, and forming a filled via that electrically connects the metal layers in the through hole; Etching the metal layer on one side to form a conductor post, etching the metal layer on the other side to form a conductor circuit, and forming a surface coating layer covering the conductor post A method for manufacturing a circuit board, comprising:
(8) The method for manufacturing a circuit board according to (7), including a step of forming an adhesive layer having a flux function on one or both surfaces of the insulating layer. (9) A plurality of the above (1) to (3) A method of manufacturing a multilayer board, wherein the circuit boards according to any one of the above are stacked in a predetermined order, and these are laminated by thermocompression bonding.
(10) An insulating base material, a circuit board having conductor circuits formed on both surfaces of the insulating base material, and at least one circuit board according to (1) or (3) are stacked in a predetermined order. A method for producing a multilayer substrate, characterized in that these are laminated by thermocompression bonding.
(11) A plurality of circuit boards according to any one of the above (1) to (3) are arranged, and these are laminated by thermocompression bonding and integrated, and a predetermined portion of a conductor circuit of each circuit board has the conductor post A method of manufacturing a multilayer substrate, wherein the layers are electrically connected to each other.
(12) An insulating base material, a circuit board having conductor circuits formed on both surfaces of the insulating base material, and at least one circuit board as described in (1) or (3) above are disposed, and these are heated. A method for manufacturing a multilayer board, wherein the predetermined parts of the conductor circuit of each circuit board are electrically connected via the conductor posts by being laminated by bonding.
(13) A multilayer substrate manufactured by stacking a plurality of circuit boards manufactured by the method according to (7) or (8) in a predetermined order, and laminating and integrating them by thermocompression bonding. Method.
(14) An insulating base material, a circuit board having conductor circuits formed on both surfaces of the insulating base material, and at least one circuit board manufactured by the method according to (7) or (8) above A method for producing a multilayer substrate, wherein the layers are laminated in a predetermined order and laminated by thermocompression bonding.
(15) A plurality of circuit boards manufactured by the method according to the above (7) or (8) are arranged, these are thermocompression bonded, laminated, and integrated, and a predetermined portion of a conductor circuit of each circuit board is the conductor. A method of manufacturing a multilayer board, wherein the electrical connection is made through a post.
(16) An insulating base material, a circuit board having conductor circuits formed on both surfaces of the insulating base material, and a plurality of circuit boards manufactured by the method according to (7) or (8) are arranged. A method for producing a multilayer board, wherein these are thermocompression bonded, laminated and integrated so that predetermined portions of the conductor circuit of each circuit board are electrically connected via the conductor post.
(17) The thermocompression bonding is performed at a first temperature at which the metal coating layer melts, and then at a second temperature lower than the first temperature. The multilayer substrate according to any one of (9) to (16), Production method.
(18) The method for producing a multilayer substrate according to (17), wherein the second temperature is a temperature suitable for curing the adhesive.
(19) A multilayer substrate manufactured by the method for manufacturing a multilayer substrate according to any one of (9) to (18).

  According to the present invention, it is possible to form a micro post with less variation in height and area, to provide a multilayer printed wiring board with higher connection reliability at the time of batch lamination, good yield, and low cost. .

  Hereinafter, although an embodiment of the present invention is described in detail, the present invention is not limited to this at all.

1 to 4 are cross-sectional views showing an embodiment when the present invention is applied to a multilayer circuit board and a manufacturing method thereof. FIG. 4B is a cross-sectional view showing a four-layer multilayer circuit board 420. The number of conductor layers is six, but two layers are connection layers and four layers are conductor circuits.
An example of a four-layer circuit board will be described as a method for manufacturing a multilayer circuit board of the present invention. As Step A (FIG. 1), a circuit board 120 with connecting conductor posts for outer layers, which is the circuit board of the present invention, is manufactured. Further, as step B (FIG. 2), the circuit board 220 with the connecting conductor posts for the inner layer, which is the circuit board of the present invention, is manufactured. In step C (FIG. 3), the double-sided circuit board 320 for the outer layer is manufactured. As Step D (FIG. 4), the circuit boards 120 and 220 are laminated on the double-sided circuit board 320 to manufacture the multilayer circuit board 420. As described above, it can be divided into four steps. The order of steps A, B, and C is not particularly limited. For example, the order of steps A, B, and C can be performed, and then step D can be performed.

In the case of stacking five or more layers, the circuit board 120 manufactured in step A is used as the outermost circuit board. What is necessary is just to laminate | stack the circuit board 220 for inner layers obtained by step B (FIG. 2) the desired number of layers from the 2nd layer after the 2nd layer counted from the circuit board 120 side.
Hereinafter, each step will be described.

(1-1) Step A
In Step A, a circuit board 120 with connecting conductor posts for outer layers is manufactured (see FIG. 1). First, for example, a double-sided laminate 110 having a copper foil 101 attached to both sides of an insulating base material 102 obtained by curing a resin such as polyimide or epoxy resin is prepared (FIG. 1A). At this time, there is no adhesive layer for bonding the copper foil 101 and the insulating base material 102 between the insulating base material 102 and the copper foil 101 in order to prevent the occurrence of smear that hinders the conductor connection. However, it may be bonded using an adhesive.

A brand via hole 106 is formed in the insulating substrate 102 (FIG. 1B), copper plating is performed, and a filled via plating 1061 is formed.
Next, a copper post 108 is formed by etching the copper foil side corresponding to the bottom surface of the blind via hole. Since the copper post obtained at this time is obtained by etching a copper foil, the height is constant, and the smoothness and roughness of the post surface are stable. Furthermore, the post shape can be freely adjusted with a photomask such as a cylinder or a quadrangular prism.

  Further, a metal coating layer 1081 for solder bonding is formed on the copper post 108 by using a plating method, a solder melting method, a paste printing method, or the like. In this case, the metal layer is a solder composed of at least one metal selected from tin, lead, silver, copper, zinc, nickel, bismuth, antimony, indium, and gold. Examples include tin, tin-lead, tin-silver, tin-zinc, tin-bismuth, tin-antimony, tin-silver-bismuth, tin-copper, etc. It is not limited to this, and an optimal one may be selected.

Although the thickness of the metal coating layer 1081 is not specifically limited, Preferably it is 7-18 micrometers, More preferably, it is 10-15 micrometers.
Further, for the purpose of preventing the generation of voids due to metal diffusion between the metal layer and the copper foil layer at the time of soldering, nickel plating may be performed for 1 to 2 μm as a base treatment.

  Next, the copper foil on the opposite surface of the conductor post 107 is etched to form the conductor circuit 103. At this time, since the conductor circuit has no precipitation of conductors other than the copper foil, it can be easily handled with a finer wire and higher density.

  Further, a surface coating 104 is applied to the conductor circuit 103 (FIG. 1 (g)). The surface coating 104 may be formed, for example, by applying an overlay film obtained by applying an adhesive to an insulating resin material or by directly printing ink on the insulating base material 102. In the configuration shown in FIG. The surface coating 104 shows a direct printing of ink. The surface coating 104 is preferably covered with a part of the conductor circuit 103 left. That is, the opening 109 may be formed on the surface coating 104 in order to mount a component or the like. At that time, surface treatment such as plating may be performed as necessary.

  Next, an adhesive 111 with a flux function is formed on the conductor post surface 107. The adhesive 111 with a flux function used here is an adhesive having a cleaning function of a metal surface, for example, a function of removing an oxide film existing on the metal surface and a function of reducing an oxide film. The composition of the agent includes a resin (A) such as a phenol novolak resin having a phenolic hydroxyl group, a cresol novolak resin, an alkylphenol novolak resin, a resole resin, or a polyvinylphenol resin, and a curing agent (B) for the resin. Curing agents are epoxidized based on bisphenol, phenol novolac, alkylphenol novolac, biphenol, naphthol, resorcinol and other skeletons such as aliphatic, cycloaliphatic and unsaturated aliphatic skeletons. Epoxy resins and isocyanate compounds

  The second preferred adhesive composition includes bisphenol-based, phenol novolak-based, alkylphenol novolak-based, biphenol-based, naphthol-based, resorcinol-based phenol bases, and skeletons such as aliphatic, cycloaliphatic and unsaturated aliphatic. An epoxy resin (C) epoxidized based on the above, an imidazole ring, and a curing agent (D) for the epoxy resin. Examples of the curing agent having an imidazole ring include imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 2-undecylimidazole, and 2-phenyl-4. -Methylimidazole, bis (2-ethyl-4-methyl-imidazole) and the like.

  The method of forming this adhesive layer 111 of this adhesive is not particularly limited. For example, there are a method of applying an adhesive with a flux function to the insulating base material 102 by a printing method, and other transfer methods. A method of laminating the agent on the insulating base material 102 is simple and preferable.

  Finally, what is obtained in FIG. 1 (g) is cut according to a desired size to obtain a circuit board 120 with connecting conductor posts for outer layers (FIG. 1 (h)).

(1-2) Step B
In Step B, a circuit board 220 with connecting conductor posts for inner layers is manufactured (see FIG. 2). First, for example, a double-sided laminated board 210 having a copper foil 201 attached to both sides of an insulating base material 202 cured with a resin such as polyimide or epoxy resin is prepared (FIG. 2A). At this time, there is no adhesive layer for bonding the copper foil 201 and the insulating base material 202 between the insulating base material 202 and the copper foil 201 in order to prevent the occurrence of smear that hinders the conductor connection. However, it may be bonded using an adhesive.

A brand via hole 206 is formed in the insulating base 202 (FIG. 2B), copper plating is performed, and a filled via plating 2061 is formed.
Next, the conductor post 208 is formed by etching the copper foil side corresponding to the bottom surface of the blind via hole. The effect obtained at this time is the same as that described in Step A above.

  Furthermore, a metal coating layer 2081 for solder bonding is formed on the conductor post 208 by using a plating method, a solder melting method, a paste printing method, or the like. The metal material constituting the metal coating layer 2081 and the preferred thickness of the metal coating layer are the same as those described in Step A above.

  Next, the copper foil on the opposite surface of the conductor post 207 is etched to form a pad 205 that can receive the conductor circuit 203 and the conductor post 107. At this time, since the conductor circuit has no precipitation of conductors other than the copper foil, it can be easily handled with a finer wire and higher density.

  Next, an adhesive 211 with a flux function is formed on the conductor post surface 207. Details of the adhesive with flux function and the method of forming the adhesive layer used here are as described above.

  Finally, what is obtained in FIG. 2 (g) is cut into a desired size to obtain a circuit board 220 with connecting posts for inner layers (FIG. 2 (h)).

(1-3) Step C
In Step C, a double-sided circuit board 320 for the outer layer is manufactured (see FIG. 3). First, for example, a double-sided laminate 310 having copper foils 301 on both sides of an insulating base material 302 obtained by curing a resin such as polyimide or epoxy resin is prepared (FIG. 3A). At this time, there is no adhesive layer for bonding the copper foil 301 and the insulating base material 302 between the insulating base material 302 and the copper foil 301 in order to prevent the occurrence of smear that hinders the conductor connection. However, it may be bonded with an adhesive.

A brand via hole 306 is formed in the insulating substrate 302 (FIG. 3B), and copper plating is performed to form a filled via plating 3061 (FIG. 3C).
Next, a pad 305 that can receive the conductor circuit 303 and the conductor post 207 is formed by etching (FIG. 3D).

  Further, a surface coating 304 is applied to the opposite surface of the pad 305 that can receive the conductor post 207 (FIG. 1 (f)). The surface coating 304 may be formed by, for example, applying an overlay film obtained by applying an adhesive to an insulating resin material, or printing ink directly on the insulating substrate 302. In the configuration shown in FIG. The surface coating 304 indicates a direct printing of ink. The surface coating 304 is preferably covered leaving a part of the conductor circuit 303. That is, an opening 309 may be formed on the surface coating 304 in order to mount a component or the like. At that time, surface treatment such as plating may be performed as necessary.

  There is no problem even if the outer double-sided circuit board 320 is cut into individual pieces before lamination. When the double-sided circuit board 320 cut into individual pieces is used, there is an advantage that the yield of the final product can be improved because only defective products can be laminated without using defective products. The same applies to the circuit boards 120 and 220.

(1-4) Step D
In Step D, the multilayer circuit board 420 is manufactured (see FIG. 4).

  First, the inner-layer circuit board 220 is laid up on the individual outer-layer double-sided circuit board 320, and the outer-layer circuit board 120 is laid up on the outer side (FIG. 4A). For the alignment, for example, a positioning mark (not shown) formed in advance on the conductor circuit of each layer is read by an image recognition device, and a positioning method or a positioning method using a positioning pin is used. be able to.

  Next, the stacked outer-layer double-sided circuit board 320, inner-layer circuit board 220, and outer-layer circuit board 120 are stacked and integrated. Such multilayering is performed while thermocompression bonding, that is, pressure bonding under heating. The specific method is as follows.

  The conductor post 107 is heated to a temperature at which solder bonding is possible (first temperature at which the metal coating layer melts), and the conductor post 107 and the metal coating layer 1081 of the conductor post 107 and the inner layer flexible via the adhesive layer 111 with a flux function. The pad portion 205 of the circuit board 220 and the conductor post 207 are melt-bonded to the metal coating layer 2081 of the conductor post 207 and the pad portion 305 of the outer double-sided substrate 320 via the adhesive layer 211 with a flux function. Then, the adhesive layers 111 and 211 with flux function are cured by reheating at the lower temperature (a temperature at which the solder does not melt and a second temperature suitable for curing the adhesive). Then, the outer layer double-sided substrate 320, the inner layer circuit substrate 220, and the outer layer circuit substrate 120 are laminated and integrated by bonding the layers (FIG. 3). (b)). Thus, in the thermocompression bonding process, a temperature difference is provided (the first half is heated at a high temperature and the second half is heated at a low temperature) to sufficiently melt the solder to prevent poor bonding, and the solder fusion bonding is performed. Immediately after being done, the adhesive layer with a flux function is cured to fix the joints of each layer, in particular, the melt-bonded part, so that a highly reliable multilayer wiring board can be obtained without causing poor conduction or the like. Show the effect.

  As a method of laminating each layer, for example, a vacuum press or a method using a combination of thermal lamination and baking can be used.

  The first temperature is preferably 170 to 270 ° C., more preferably 185 to 260 ° C., and the second temperature is preferably 120 to 200 ° C., more preferably 150 to 190 ° C. Can do.

  Thus, a multilayer circuit board 420 in which the outer layer double-sided circuit board 320, the inner layer circuit board 220, and the outer layer circuit board 120 are laminated is obtained.

  1 to 4, the configuration in which the number of circuit layers is four has been described. However, in the present invention, a three-layer configuration in which the outer-layer circuit board 120 and the outer-layer double-sided circuit board 320 are laid up, or an outer-layer circuit board is used. Is used as the outermost circuit board, and a multilayer circuit board of five or more layers in which a desired number of inner-layer circuit boards are laminated between the second and subsequent layers, counting from the outer-layer circuit board side, between the outer-layer double-sided circuit boards is also available. included.

(Example 1)
[Production of double-sided printed wiring board for inner layer]
A dry film photoresist is laminated on one side as a protective film on a double-sided copper-clad laminate having a copper foil thickness of 12 μm and an epoxy resin thickness of 60 μm. In this state, dry film photoresist, single-sided copper foil, and epoxy resin are removed by UV laser to form IVH having a diameter of 50 μm. At this time, a positioning hole for lamination is also formed. Furthermore, this IVH performs dry desmear using low-pressure plasma. Subsequently, the other copper foil surface is fed and sealed with a plating jig, and about 70 μm of copper plating is deposited from the bottom of IVH by electrolytic copper plating. Next, after removing the dry film photoresist with sodium hydroxide, the dry film photoresist is again laminated on both sides, and a double-sided printed wiring board is produced by exposure, development, and etching.

[Production of double-sided printed wiring board with conductor posts for outer layer]
Similarly, a dry film photoresist is laminated on one side as a protective film on a double-sided copper-clad laminate having a copper foil thickness of 12 μm and an epoxy resin thickness of 60 μm. In this state, the dry film resist, single-sided copper foil, and epoxy resin are removed by UV laser to form IVH having a diameter of 50 μm. At this time, a positioning hole for lamination is also formed. Furthermore, this IVH performs dry desmear using low-pressure plasma. Subsequently, the other copper foil surface is fed and sealed with a plating jig, and about 70 μm of copper plating is deposited from the bottom of IVH by electrolytic copper plating. Next, after removing the dry film photoresist with sodium hydroxide, the dry film photoresist is again laminated on both sides, and a conductor post is formed on the copper foil surface not subjected to laser processing by exposure, development and etching. Subsequently, the conductor layer on the back surface of the conductor post is fed and sealed with a plating jig to form about 10 to 15 μm of lead-free solder plating made of tin-silver on the conductor post.
Next, a dry film photoresist is laminated on both surfaces, and a wiring pattern is formed on the conductor layer opposite to the conductor post by exposure, development, and etching. Finally, an adhesive layer with a flux function is laminated on the entire surface of the conductor post. Prepare these for the number of layers.

[Production of multilayer printed wiring boards]
The double-sided printed wiring board for the inner layer is used as a core layer, and the double-sided printed wiring board with a conductor post for exterior use is laid up using alignment pins. Then, after temporary bonding with a vacuum pressure laminator at 130 ° C, 0.2 MPa, 30 seconds, press at 300 ° C, 0.05 MPa for 3 minutes to melt the lead-free solder on the surface of the conductor post, with a flux function A metal connection is formed with the wiring pattern of the printed wiring board overlapping through the adhesive layer. Furthermore, it is baked at 180 ° C. for 1 hour to cure and laminate the adhesive layer. Finally, the outermost layer is covered with a solder resist, and a surface treatment is performed on the terminal portion for mounting by plating or the like to obtain a multilayer printed wiring board.
(Example 2)

The double-sided printed wiring board for the inner layer is a double-sided flexible wiring board, and press conditions after layup are temporarily bonded at 100 ° C., 0.1 MPa, 30 seconds with a vacuum pressure laminator, then at 300 ° C., 0.002 MPa. A flex-rigid wiring board obtained by the same method as in Example 1 except that it is pressed for 3 minutes (Example 3)

  The double-sided printed wiring board for inner layer and outer layer is a double-sided flexible wiring board, and the press conditions after lay-up are temporarily bonded at 100 ° C., 0.1 MPa, 30 seconds with a vacuum pressure laminator, then 300 ° C., 0 .Multilayer flexible printed wiring board obtained by the same method as in Example 1 except that pressing is performed at 0002 MPa for 3 minutes.

  The present invention relates to a method for producing a print used as a component of an electronic device.

It is sectional drawing for demonstrating the outer-layer circuit board and its manufacturing method of this invention. It is sectional drawing for demonstrating the inner-layer circuit board and its manufacturing method of this invention. It is sectional drawing for demonstrating the outer-layer double-sided circuit board and its manufacturing method of this invention. It is sectional drawing for demonstrating the multilayer circuit board and its manufacturing method of this invention.

Explanation of symbols

101, 201, 301: Copper foil 102, 202, 302: Insulating base material 103, 203, 303: Conductor circuit 104, 304: Surface coating 106, 206, 303: Blind via hole 1061, 2061, 3031: Filled via plating 107, 207: Conductor post 108, 208: Copper post 1081, 2081: Metal coating layer 109, 309: Openings 110, 210, 310: Laminate plate 111, 211: Adhesive 120, 220, 320, 420 with flux function: Circuit board , Multilayer substrates 205, 305: pads for receiving conductor posts

Claims (19)

An insulating substrate;
It has a conductor circuit formed on one surface side of the insulating substrate and a conductor post formed by etching on the other surface side, and the conductor circuit and the conductor post are electrically connected by a filled via. The circuit board is characterized in that the conductor post is covered with a metal coating layer. The metal coating layer is formed of at least one metal selected from the group consisting of gold, silver, nickel, tin, lead, zinc, bismuth, antimony, indium, and copper, or an alloy containing the metal. Circuit board as described. The circuit board according to claim 1, wherein an adhesive layer having a flux function is provided on one side or both sides of the insulating base material. A multilayer board comprising a plurality of circuit boards including the circuit board according to claim 1. A plurality of circuit boards comprising an insulating base material, a circuit board having a conductor circuit formed on both surfaces of the insulating base material, and the circuit board according to any one of claims 1 to 3 are laminated. A multilayer board characterized by An insulating base material, a circuit board having conductor circuits respectively formed on both surfaces of the insulating base material, and the circuit board according to any one of claims 1 to 3, are joined, and each of the circuit boards is interposed via the conductor post. A multilayer board, wherein predetermined portions of a conductor circuit of a circuit board are electrically connected. A step of forming a through hole in the insulating base material in which a metal layer serving as a conductor circuit is formed on each side of the insulating base material, and forming a filled via that electrically connects the metal layers in the through hole; Etching the side metal layer to form a conductor post, etching the other side metal layer to form a conductor circuit, and forming a surface coating layer covering the conductor post. A method of manufacturing a circuit board. The method for manufacturing a circuit board according to claim 7, further comprising a step of forming an adhesive layer having a flux function on one side or both sides of the insulating layer. A method for manufacturing a multilayer board, comprising: stacking a plurality of circuit boards according to any one of claims 1 to 3 in a predetermined order, and laminating and integrating them by thermocompression bonding. An insulating base material, a circuit board having a conductor circuit formed on both surfaces of the insulating base material, and at least one circuit board according to claim 1 are stacked in a predetermined order, and these are thermocompression bonded. A method of manufacturing a multilayer substrate, characterized by stacking and integrating. A plurality of circuit boards according to any one of claims 1 to 3 are arranged, and these are laminated by thermocompression bonding and integrated, and predetermined portions of the conductor circuits of each circuit board are electrically connected via the conductor posts. A method for producing a multilayer substrate, characterized in that: An insulating base material, a circuit board having a conductor circuit formed on both surfaces of the insulating base material, and at least one circuit board according to claim 1 are arranged, and these are laminated by thermocompression bonding. A method of manufacturing a multilayer board, wherein predetermined portions of the conductor circuit of each circuit board are electrically connected via the conductor post. A method for manufacturing a multilayer board, comprising: stacking a plurality of circuit boards manufactured by the method according to claim 7 or 8 in a predetermined order, and laminating and integrating them by thermocompression bonding. An insulating base material, a circuit board having conductor circuits respectively formed on both surfaces of the insulating base material, and at least one circuit board manufactured by the method according to claim 7 or 8, are stacked in a predetermined order, A method for producing a multilayer substrate, characterized in that these are laminated by thermocompression bonding. A plurality of circuit boards manufactured by the method according to claim 7 or 8 are arranged, and these are laminated by thermocompression bonding, and a predetermined portion of a conductor circuit of each circuit board is electrically connected via the conductor post. A method for producing a multilayer substrate, characterized in that the multilayer substrate is connected to the substrate. An insulating base material, a circuit board having a conductor circuit formed on both surfaces of the insulating base material, and a plurality of circuit boards manufactured by the method according to claim 7 or 8 are disposed, and these are thermocompression bonded. A method of manufacturing a multilayer board, wherein a predetermined portion of a conductor circuit of each circuit board is electrically connected via the conductor post. The method for manufacturing a multilayer substrate according to any one of claims 9 to 16, wherein the thermocompression bonding is performed at a first temperature at which the metal coating layer melts and then at a second temperature lower than the first temperature. The method for manufacturing a multilayer substrate according to claim 17, wherein the second temperature is a temperature suitable for curing the adhesive. A multilayer substrate manufactured by the method for manufacturing a multilayer substrate according to claim 9.

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