JP2001244591A - Wiring board and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board together with its manufacturing method where a via connecting wiring layers is formed without a laborious plating process. SOLUTION: A wiring board 100 comprising, at its center, a metal plate 101, and first and second insulating layers 103 and 105 are formed on its upper and lower surfaces 101a and 101b while an in-hole insulating layer 107 is provided in a through hole 101h. A metal pillar 109 penetrates the first and second insulating layers 103 and 105 as well as the in-hole insulating layer 107. The metal pillar 109 has a pre-molded copper wire embedded in each insulating layer, connecting first and second wiring layers 111 and 112. The first wiring layer 111 has a first via 113 comprising copper wire erected, which is embedded in a first inter-layer insulating layer 115 formed on the first insulating layer 103 and the first wiring layer 111. The first via 113 connects the first wiring layer 111 to a third wiring layer 117. Vias 114, 119, and 120 comprise a wire as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board and a method of manufacturing the same, and more particularly, to a wiring board in which a plurality of wiring layers and the like arranged via an insulating layer are connected by wires and the like, and a method of manufacturing the same. About.

[0002]

2. Description of the Related Art Conventionally, in a resin wiring board,
Glass-epoxy resin composite material (hereinafter, referred to as core substrate)
A wiring board using a composite material such as glass epoxy) and alternately stacking wiring layers made of copper or the like and insulating layers made of a resin or a composite material is known.

For example, a wiring board 20 shown in FIG. 18 has a core board 1 made of glass epoxy. The core substrate 1 is formed with a through hole 2 penetrating between the upper and lower surfaces 1a and 1b. A through-hole conductor 3 made of copper and connecting the upper and lower surfaces is formed on the inner periphery and the upper and lower surfaces of the through hole 2. Electrically connected. On the upper surface 1a side and the lower surface 1b side of the core substrate 1, wiring layers and insulating layers are alternately formed, respectively. In this example, each of the wiring layers is 5a, 5b, 6a, and 6b.
The layers and the insulating layers are each formed of two layers 7a, 7b, 8a and 8b. Further, vias (via wirings) 9a, 9b, 10 penetrating through the insulating layers and connecting between the wiring layers, respectively.
a, 10b are also formed.

[0004] To form such a wiring board 20,
First, a through-hole 2 is formed by drilling a core substrate 1 made of already cured glass epoxy with a drill or the like, and then a through-hole conductor 3 having a predetermined pattern is formed by copper plating and etching. Further, a resin paste is applied, a through hole for a via is opened at a predetermined position, and then cured to form insulating layers 7a and 8a. Next, vias 9a and 10a are formed in the via holes by copper plating, and the surfaces of the insulating layers 7a and 8a are adjusted. Then, the insulating layer 7
Wiring layers 5a and 6a are formed on the surfaces of a and 8a by plating using a known method such as a subtractive method. Further, similarly, insulating layers 7b, 8b, vias 9b, 10b
And the wiring layers 5b and 6b are formed.

[0005]

SUMMARY OF THE INVENTION Such a wiring board 2
0, as described above, in order to maintain the strength of the wiring board, a composite material such as a glass-epoxy resin composite material in which a resin such as epoxy is impregnated in glass cloth or the like is used for the core substrate 1. Many. However, when the through hole 2 is formed in the core substrate 1, fine cracks occur between the glass fiber and the resin that has been impregnated and already hardened, and a plating or cleaning step when forming the through-hole conductor 3 is performed. In some cases, moisture may enter the crack. For this reason, the insulation resistance may be reduced due to the occurrence of migration or the like. In severe cases, an electrical short circuit may occur between the adjacent through-hole conductors 3. Therefore, in order to obtain a certain insulation distance, it is necessary to make the distance between the through-hole conductors 3 and therefore the distance between the through-holes 2 relatively large.

When the through-hole conductor 3 is formed, it is necessary to reliably plate the inner periphery of the through-hole 2. When the diameter of the through hole 2 is reduced, it becomes difficult to perform plating in the through hole 2 and the yield is reduced. Further, in order to form the through-hole conductor 3, a plating resist omitted in the above description,
It is necessary to go through steps such as formation of a through-hole conductor by plating, cleaning, etching, and the like, which is troublesome. Further, an apparatus for plating, cleaning, etching, and the like, and an apparatus for processing chemicals are required, which is expensive.

[0007] Similarly, vias (for example, 9a) connecting between wiring layers are required as the wiring layers are made finer.
It is necessary to reduce the diameter of the via. However, when the diameter of the via is reduced, it becomes difficult to reliably perform plating in the via through hole. The fact that many steps and devices are required for plating is also the same when forming vias.

[0008] Further, the through-hole conductors and vias formed by plating are compared with preformed metal plates and wires.
The resistance is slightly higher due to low conductivity. In addition, since the strength is low, when stress is applied to vias and the like due to the difference in the coefficient of thermal expansion between the wiring layer made of metal such as copper and the core substrate or insulating layer made of resin or composite material, the through hole It is also conceivable that a conductor or via cracks and breaks.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to make connections between wirings in the vertical direction while maintaining the strength of a wiring board and not to cause a decrease in insulation resistance. And a highly reliable wiring board and a method of manufacturing the same. Another object of the present invention is to provide a wiring board having vias connecting between wiring layers without using a complicated plating process, and a method of manufacturing the same.

[0010]

In order to solve the problem, action and effect] or not a
A core substrate having an upper surface and a lower surface and having a plurality of through holes, an in-hole insulating layer filled in the through holes, a first insulating layer formed on an upper surface of the core substrate, A second insulating layer formed on the lower surface of the core substrate; a plurality of first wiring layers formed on the upper surface of the first insulating layer; and a plurality of second wiring layers formed on the lower surface of the second insulating layer And a metal penetrating the first insulating layer, the in-hole insulating layer, and the second insulating layer, and connecting any one of the plurality of first wiring layers and any one of the plurality of second wiring layers. It is preferable that the wiring board be a pillar, which is formed in advance and has an interlayer metal pillar embedded in the first insulating layer, the second insulating layer, and the in-hole insulating layer. .

In this case, the through-hole conductor is not formed on the inner peripheral surface of the through-hole, and the insulating layer in the hole is interposed between the interlayer metal pillar passing through the through-hole and the through-hole. . The insulating layer in the hole maintains insulation between the metal pillars for interlayer and the core substrate or between adjacent metal pillars for interlayer. Further, the metal pillar for interlayer penetrating through the insulating layer in the hole is formed in advance and does not go through a plating step. Therefore, unlike a conventional wiring board, moisture does not penetrate into cracks generated in the core substrate and insulation resistance does not decrease, so that a highly reliable wiring board can be obtained. Further, since the first and second insulating layers and the in-hole insulating layer bury the interlayer metal pillars therein to maintain insulation, the distance between the metal pillars (thus, the through holes of the core substrate) is reduced. Thus, a wiring board with high-density wiring can be obtained.

Further, since the core substrate is sandwiched between the first insulating layer and the second insulating layer, the strength and rigidity such as the bending strength of the entire wiring substrate can be determined by selecting the material and thickness of the core substrate. Can also be adjusted. Further, since the metal pillar for interlayer is formed in advance, it is denser and has higher conductivity than through-hole conductors formed by plating.
In addition, since it has high durability against tensile stress, repeated bending stress, and the like, it does not break due to cracks due to stress.

Since the core substrate is insulated from the interlayer metal pillar by the insulating layer in the hole, the core substrate may be selected in consideration of the coefficient of thermal expansion, thermal conductivity, bending strength, bending rigidity, and the like.
The material may be not only an insulating (non-conductive) material but also a conductive material. Therefore, ceramics and glass such as alumina, mullite, aluminum nitride, etc., resins such as epoxy resin, polyimide resin and BT resin, or composites of these resins with polymer fibers such as glass fibers and polyester fibers, metal fibers and carbon fibers Materials (for example, glass epoxy), composite materials of these resins and ceramic powder, and the like are included. Further, metals such as copper, copper alloy, aluminum, and aluminum alloy may be used. Further, there may be mentioned one in which only one or both surfaces are made of metal. For example, a layered composite material of a metal plate and an insulating plate, such as a single-sided or double-sided copper-clad insulating plate, in which a metal plate such as a copper plate is attached to one or both surfaces of an insulating plate made of glass epoxy or the like, may be used.

Further, the material of the insulating layer in the hole may be selected in consideration of heat resistance, hygroscopicity and the like, and examples thereof include resins such as epoxy resin, polyimide resin and BT resin.
The resin may contain an inorganic substance such as silica, a filler of a plastic powder, and the like. Further, a composite material of a resin and a ceramic powder may be used. Also, the material of the first and second insulating layers may be selected in consideration of heat resistance, hygroscopicity, and the like. Specifically, resins such as epoxy resin, polyimide resin, and BT resin; Examples include a composite material of a resin such as an epoxy resin composite material, a glass-BT resin composite material, a polyester fiber-epoxy resin composite material and a glass fiber or a polymer fiber, and a composite material of a resin and a ceramic powder.

The material of the metal pillar for interlayer is preferably one having high conductivity and appropriate rigidity.
Gold, silver, aluminum and the like. More specifically, it is preferable to use a wire (bonding wire) used for wire bonding because it is easily available. The material of the first and second wiring layers may be selected in consideration of conductivity and the like, and examples thereof include copper, silver, gold, and nickel. In this specification, the terms “upper surface” and “lower surface” are used. Not something. Further, when another layer or the like is formed on the upper surface or the lower surface of a certain layer, the upper surface, the lower surface, and the like may be expressed. Point to.

Next, in the above wiring board, the core board is a metal surface core board in which at least one of an upper surface and a lower surface is made of metal.
Is also preferable .

With this configuration , at least one of the upper surface and the lower surface of the core substrate is made of metal, so that a shielding effect can be obtained between the first and second wiring layers formed above and below the metal surface core substrate, Noise can be prevented from entering signal wiring and the like. Further, since at least one of the upper surface and the lower surface of the core substrate is made of metal, the thermal conductivity of the entire wiring substrate is improved, and, for example, heat generated from an integrated circuit chip or the like can be quickly released to the entire wiring substrate. In addition, heat dissipation can be improved.

Here, as the metal constituting the upper and lower surfaces of the metal surface core substrate, those having high conductivity, appropriate rigidity, and easy to process are preferable. Specifically, copper, brass, Bronze, silver, aluminum, aluminum alloy and the like can be mentioned. Examples of such a metal surface core substrate include those in which the entire core substrate is made of metal, and those in which only one or both surfaces are made of metal. For example, a metal plate such as a copper plate or the like is attached to one or both sides of an insulating plate made of a resin material such as epoxy, a composite material such as glass epoxy, ceramic, or the like. It may be a layered composite of a board and an insulating board.

Further, in the above wiring board, the first
A metal pillar penetrating an insulating layer and connecting any one of the plurality of first wiring layers to an upper surface made of metal of the metal surface core substrate, which is formed in advance and embedded in the first insulating layer. A first metal pillar for a core, and a metal pillar penetrating through the second insulating layer and connecting any one of the plurality of second wiring layers to a lower surface made of metal of the metal surface core substrate. The wiring board is characterized by having at least one of a second core metal pillar formed in advance and embedded in the second insulating layer.
Preferred .

That is, in this wiring board, the entire core board is made of metal, such as a copper plate, and a metal pillar for the core is provided on at least one of the upper and lower surfaces thereof. (Upper and lower surfaces) are made of metal and at least one of the upper and lower surfaces is provided with a core metal column, and one of the upper and lower surfaces of the core substrate is made of metal such as a single-sided copper-clad insulating plate. And those in which a core metal column is formed on a surface made of the metal.

With this configuration, the upper surface or the lower surface made of the metal of the metal surface core substrate is connected to the first or second wiring layer via the first or second core metal pillar. For this reason, the upper surface or the lower surface of the core substrate can be used as a power supply potential layer, a ground potential layer, or a signal wiring, like the first and second wiring layers. In particular, when the upper surface or the lower surface of the metal surface core substrate is used at the power supply potential or the ground potential, that is, when the upper surface or the lower surface of the core substrate is used as the power plane or the ground plane, the wiring layer is used as the power plane or the like. Since the area can be increased as compared with the above, the potential of the power supply or the ground can be easily taken out from a required position. Also,
It can be easily connected to power supply and ground wiring. In addition, the metal of the metal surface core substrate can be made thicker than the wiring layer, so that the resistance and inductance generated in the plane can be reduced, and the electrical characteristics of the wiring substrate can be improved.

In particular, when a metal surface core substrate having a structure in which upper and lower surfaces of an insulating plate made of glass epoxy or the like are sandwiched between thin metal plates is used, the upper surface and the lower surface of the metal surface core substrate may be, for example, an upper surface. Can be different potentials, such as a ground and a power supply on the lower surface. In this case, the metal surface core substrate can also serve as a capacitor.

The material of the first core metal pillar and the second core metal pillar is preferably the same as the material of the interlayer metal pillar. That is, those having high conductivity and moderate rigidity are good, for example, copper, copper alloy, gold, silver, aluminum,
Aluminum alloy and the like can be mentioned. More specifically, it is preferable to use a wire (bonding wire) used for wire bonding because it is easily available.

Next, a core substrate having an upper surface and a lower surface and having a plurality of through holes, a bottom plate, and an interlayer metal column erected at a position corresponding to the through hole of the core substrate on the upper surface of the bottom plate. And a metal pillar standing body comprising a combination of the lower surface of the core substrate and the upper surface of the bottom plate facing each other so that the interlayer metal pillar penetrates the through hole.
A step of disposing an uncured insulator between at least the lower surface of the core substrate and the upper surface of the bottom plate and on the upper surface of the core substrate; (2) forming an insulating layer and a first insulating layer on the upper surface side, removing the bottom plate, leveling the upper surface of the first insulating layer and the lower surface of the second insulating layer, respectively, A step of exposing an upper end portion and a lower end portion, respectively, and a first wiring layer and a second wiring respectively connected to the exposed interlayer metal pillar on the upper surface of the first insulating layer and the lower surface of the second insulating layer. that the method of manufacturing a wiring board having a step of forming a layer, are preferred.

With this arrangement, the metal pillar for interlayer is assembled so as to penetrate through the through hole of the core substrate, and then the uncured insulating material is cured, so that the inside of the hole is surrounded by the metal pillar for interlayer. An insulating layer and first and second insulating layers are formed. Therefore, no crack is generated in the in-hole insulating layer or the first and second insulating layers in contact with the interlayer metal pillars, and no plating solution or the like is used, so that a highly reliable wiring board can be obtained. . Further, as in the case of a conventional through-hole conductor, a metal pillar for interlayer which can conduct vertically can be formed irrespective of plating, so that the process is simplified. In addition, since the interlayer metal pillars formed in advance are buried in the first, second, and in-hole insulating layers, the conductivity is increased unlike through-hole conductors formed by plating. Also, the durability against stress is increased, so that breakage due to stress does not occur.

Here, the uncured insulating material contains an uncured resin, and may be only an uncured resin, or may be a material partially containing a glass fiber or a polymer fiber such as polyester. good. Here, as the uncured resin,
Epoxy, polyimide, BT and other thermosetting resins in an uncured state may be used. The uncured resin may contain a filler such as an inorganic substance such as silica or a plastic powder. Specifically, in addition to a resin paste such as an epoxy resin paste, a prepreg having a resin paste such as an epoxy resin in a semi-cured state, or a resin such as a glass non-woven fabric impregnated with a resin paste such as an epoxy resin to have a semi-cured state. Prepreg and the like.

The material of the bottom plate is selected in consideration of the material of the metal pillar for interlayer, the method of forming the metal pillar standing body, and the like.
Examples thereof include a metal plate made of copper, brass, aluminum, or the like, or a resin substrate made of glass epoxy or the like, which is formed by attaching or plating a copper layer or the like. Further, examples of the method of adjusting the surface include surface grinding with a grinding wheel, buffing, and the like.

Further, as the metal pillar standing body, there is a metal pillar formed by erecting a wire at a predetermined position on the surface of the bottom plate by a wire bonding method. That is, in the manufacturing method of the wiring substrate, the metal pillar stand設体is by wire bonding method, fixed at one end of the wire to a predetermined position of the surface of the bottom plate, and comprising a metal body erected the wire It is good to be characterized by being a metal pillar standing body.
In this case, a metal pillar having a desired height can be easily formed at a desired position. For this reason, it is possible to easily cope with the production of a small number of products, a change in design, and the production of a prototype. In this case, the bottom plate may be a metal plate or may be formed by attaching or plating a copper layer or the like on the surface of a resin substrate such as glass epoxy.

Further, as the metal column standing body, a metal plate formed by etching a metal plate from one surface to leave a portion near the metal column and the other surface may be used. That is, in the method for manufacturing a wiring board described above , the metal pillar standing body is formed by etching the standing body metal plate from one surface and leaving the metal pillar and a portion near the other surface. It is good to be characterized by being a metal pillar standing body.

By doing so, a metal pillar standing body having many metal pillars standing can be formed at once. For this reason, in the case where a large number of metal columns are required, it can be manufactured at low cost. Further, since the metal column and the bottom plate are integrated, the metal column does not fall off. Further, as a method of forming the metal pillar standing body, a method of welding a metal wire or a metal pillar to the bottom plate via a brazing material can be cited.

The method of arranging the uncured insulator is as follows.
When a resin paste is used, the resin paste is applied to the upper surface of the bottom plate of the metal column standing body, the upper and lower surfaces of the core substrate, and the like by a spray method, an electrostatic spray method, a curtain coating method, a die coating method, a spin coating method, or the like. Method. That is, in the manufacturing method of the wiring substrate, placing the uncured insulating material, applying a resin paste to at least one of the lower surface of the upper surface and the core substrate of the bottom plate,
The method may be characterized in that the metal pillar standing body and the core substrate are overlapped, and a resin paste is applied to the upper surface of the core substrate. In this way, regardless of the arrangement of the metal columns and the through holes, the uncured insulator can be reliably arranged, and operations such as preparing a prepreg having a through hole formed in advance at a position corresponding to the metal columns can be performed. It becomes unnecessary.

As a method of arranging the uncured insulator, a prepreg having a through hole (through hole for a metal pillar) previously prepared at a position corresponding to the metal pillar for an interlayer is prepared, and the metal pillar for an interlayer is provided in the through hole. There is a method in which the prepreg is stacked on the upper surface of the bottom plate or the prepreg is stacked on the upper surface of the core substrate so as to penetrate. That is, in the manufacturing method of the wiring substrate, the step of placing the uncured insulating material, and the metal pillars standing設体second spaced metal posts through holes at positions corresponding to the advance of the interlayer metal pillar The method may be characterized in that it is a step of laminating a prepreg, the core substrate, and a first prepreg in which a through hole for a metal pillar is previously opened at a position corresponding to the metal pillar for an interlayer.

In this way, the first and second insulating layers can be easily formed only by stacking the prepreg on the metal pillar standing body or the core substrate and curing the prepreg. In addition,
In order to cure the prepreg, it is sufficient to simply heat, but it is preferable to heat while pressing by a vacuum hot press. This is because the resin reliably flows into the through holes of the core substrate and the through holes for the metal pillars, and these through holes can be reliably filled.

Since the resin of the prepreg flows by heating and fills the through holes of the core substrate, an in-hole insulating layer is also formed. That is, when the prepreg to be used is obtained by semi-curing a resin, both the in-hole insulating layer and the first and second insulating layers are resin insulating layers. On the other hand, when the prepreg is made of a fiber (a glass nonwoven fabric or the like) impregnated with a resin paste to be in a semi-cured state, only the resin flows and fills the through holes of the core substrate. The insulating layer is made of resin, and the first and second insulating layers are made of a composite material of resin and fiber such as glass fiber. In this case, since the first and second insulating layers are reinforced with glass fibers or the like, the strength of the entire wiring board can be improved.

In addition, a resin paste may be filled in the through holes of the core substrate before or during the overlapping of the first and second prepregs with the core substrate or the metal pillar standing body. By doing so, the resin is more reliably filled in the through-hole, and the in-hole insulating layer can be reliably formed.

In some cases, these methods may be combined. That is, a prepreg is sandwiched between the bottom plate of the metal standing body and the core substrate, and the upper surface of the core substrate is
A resin paste may be applied. Conversely, a resin paste may be applied to the upper surface of the bottom plate, the core substrate may be stacked, and the prepreg may be stacked on the upper surface of the core substrate.

Further, in the above-mentioned method for manufacturing a wiring board, the core substrate may be formed of a metal at least one of the upper surface and the lower surface, and the first core metal column and the metal formed on the metal upper surface. A metal surface core substrate having at least one of a second core metal pillar formed on a lower surface made of a metal core core substrate, wherein in the step of exposing upper and lower ends of the interlayer metal pillar, the metal surface core substrate is formed on the metal surface core substrate. In the step of exposing the tops of the first core metal pillar and the second core metal pillar, and forming the first and second wiring layers, the first and second core metal pillars are connected to the exposed first and second core metal pillars. It is preferable to provide a method for manufacturing a wiring board, wherein first and second wiring layers are also formed.

In this wiring board , at least one of the upper surface and the lower surface of the core substrate is made of a metal. Is formed. Moreover,
In the step of exposing the upper and lower ends of the interlayer metal pillar, the tops of the first core metal pillar and the second core metal pillar formed on the metal surface core substrate are also exposed. In addition, the first,
In the step of forming the second wiring layer, first and second wiring layers connected to the exposed first and second core metal columns are also formed.

That is, when the first core metal pillar is formed on the upper surface of the metal surface core substrate, in the step of exposing the upper and lower ends of the interlayer metal pillar, the top of the first core metal pillar is removed. In the step of exposing and further forming the first and second wiring layers, a first wiring layer connected thereto is formed. Similarly, when the metal pillar for the second core is formed on the lower surface of the metal surface core substrate, the top of the metal pillar for the second core is exposed, and further, a second wiring layer connected to the metal pillar is formed. . Further, when the first core metal pillar is formed on the upper surface of the metal surface core substrate and the second core metal pillar is formed on the lower surface, the tops of the first and second core metal pillars are respectively exposed, In addition, the first and the second
Form a wiring layer.

Therefore, at least one of the upper surface and the lower surface of the metal surface core substrate is connected to the first and second wiring layers by the first and second core metal pillars. Can be used as a ground potential layer, a power supply potential layer, or a signal wiring. In addition, since the first and second core metal pillars are formed in advance on the upper and lower surfaces of the metal surface core substrate, these core metal pillars are embedded in the first and second insulating layers. It can be formed without a plating process, and the process is simplified.

As a method of forming the first and second core metal columns, a method in which wires are erected at predetermined positions on the upper surface and the lower surface of the metal surface core substrate by a wire bonding method may be used. That is, in the manufacturing method of the wiring substrate, the metal column for the first core and the second core metal pillar,
It is preferable that one end of the wire is fixed to predetermined positions on the upper surface and the lower surface of the metal surface core substrate by a wire bonding method, and the wire is formed upright.
By doing so, the first and second metal columns having a desired height can be easily formed at desired positions. For this reason, it is possible to easily cope with the production of a small number of products, a change in design, and the production of a prototype.

Further, as a method of forming the first and second core metal pillars, a metal plate is etched from one or both surfaces, and at least one of the first and second core metal pillars is formed of metal. There is also one formed so as to leave the surface core substrate portion. That is, in the manufacturing method of the wiring board, the first core metal columns and the second
The metal surface core substrate having at least one of the metal pillars for the core is formed by etching the metal plate for the core from one or both surfaces, and forming the metal plate for the first core and the metal pillar for the second core from at least one of the metal and the metal. It is good to be characterized in that it is a metal pillar standing body formed by leaving a part of the metal surface core substrate.

By doing so, a metal surface core substrate on which many first and second metal columns are erected can be formed at once.
For this reason, in the case where a large number of first and second core metal pillars are required, it can be manufactured at low cost. Further, since the first and second core metal columns and the metal surface core substrate are integrated, the first and second core metal columns do not fall off. Further, as a method of forming the metal surface core substrate having the first and second core metal columns, a metal wire or the first and second core metal columns are welded to the metal surface of the metal surface core substrate via a brazing material. There is also a method of doing. Further, the first and second core metal columns may be formed on the upper surface of the metal surface core substrate by plating.

Further, according to a first aspect of the present invention, there is provided a lower wiring layer, an upper wiring layer, an interlayer insulating layer interposed between the lower wiring layer and the upper wiring layer, and the lower wiring layer and the upper wiring. A wiring board having vias for connecting layers with each other, the vias being formed of wires formed in advance and embedded in the interlayer insulating layer.

According to the present invention, since the via is made of a preformed wire, the conductivity of the via can be made higher than when the via is formed by plating or the like. Further, since the strength is high, the via does not crack even if stress is applied to the via due to a difference in thermal expansion coefficient between the upper wiring layer or the lower wiring layer and the interlayer insulating layer. Also, in order to change the diameter of the via in consideration of conductivity and strength, it is sufficient to change the diameter of the wire.

Here, examples of the material of the wire forming the via include copper, copper alloy silver, gold, aluminum, and aluminum alloy, and the material may be selected in consideration of the material of the lower and upper wiring layers. The material of the lower wiring layer and the upper wiring layer includes copper, silver, gold, nickel and the like. Further, as the material of the interlayer insulating layer, resins such as epoxy, polyimide, and BT, and composite materials of these resins with glass fibers, polymer fibers, and the like can be used.

Further, according to a second aspect of the present invention, one end of a wire is fixed to a predetermined position on an upper surface of a lower wiring layer formed on a lower insulating layer by a wire bonding method, and the wire is fixed to a predetermined position. Forming a via standing upright, placing an uncured insulator on the upper surface of the lower insulating layer and the upper surface of the lower wiring layer with the via standing, and heating the uncured insulator. Curing the insulator to form an interlayer insulating layer, leveling the upper surface of the interlayer insulating layer to expose the top of the via, and connecting the exposed via to the upper surface of the interlayer insulating layer. Forming an upper wiring layer to be formed.

According to the present invention, a via using a wire formed in advance by a wire bonding method can be formed. Since the wire is formed in advance, the step of forming the wire by plating or the like as in the related art is not required, and a plating solution using various chemicals, a plating device, a cleaning device, and the like are not required, so that the wire can be formed at low cost. In addition, since a preformed wire is used, the via has high conductivity and high strength.

Here, at a predetermined position on the upper surface of the lower wiring layer,
As a method for erecting the wire by the wire bonding method, a known technique may be used. For example, one end of the wire is fixed to the lower wiring layer by thermocompression bonding or ultrasonic compression bonding.

When a resin paste is used as a method for disposing the uncured insulator, the resin paste is applied onto the lower insulating layer and the lower wiring layer by a spray method, a calendar method, a spin coating method, or the like. Method. That is, in the method for manufacturing a wiring board according to claim 2, the step of disposing the uncured insulator is a step of applying a resin paste to the upper surfaces of the lower insulating layer and the lower wiring layer. good. In this case, the uncured insulator can be reliably disposed regardless of the arrangement of the standing vias, and the work of forming a through-hole in the prepreg in advance becomes unnecessary.

As a method for arranging the uncured insulator, a prepreg having a through hole (via through hole) at a position corresponding to a via which has been set up in advance is prepared, and the via is passed through the through hole. Then, there is a method of stacking a prepreg on the upper surfaces of the lower insulating layer and the lower wiring layer. That is, in the method of manufacturing a wiring board according to claim 2, the step of arranging the uncured insulator includes: forming a prepreg having a through-hole for a via at a position corresponding to the erected via in advance; In addition, it is preferable to overlap with the upper surface of the lower wiring layer.

That is, one end of the wire is fixed to a predetermined position on the upper surface of the lower wiring layer formed on the lower insulating layer by a wire bonding method, and the wire is fixed at a predetermined height. Forming a via standing in the
A step of superimposing a prepreg having a through hole for a via at a position corresponding to the via standing in advance on the upper surface of the lower insulating layer and the upper surface of the lower wiring layer while the via is standing,
Heating and curing the prepreg to form an interlayer insulating layer, leveling the upper surface of the interlayer insulating layer, exposing the top of the via, and exposing the upper surface of the interlayer insulating layer to the upper surface of the interlayer insulating layer. Forming an upper wiring layer connected to the via;
And a method of manufacturing a wiring board having the following.

In this way, in addition to the functions and effects obtained by the second aspect of the present invention, the lower insulating layer and the lower wiring layer are stacked on the prepreg, and the prepreg is cured, and the interlayer is easily formed. An insulating layer can be formed. In addition,
As described above, prepregs include those in which a resin paste is in a semi-cured state, those in which a resin such as a glass nonwoven fabric is impregnated with a resin paste to be in a semi-cured state, and the like. Although heating may be performed simply, it is desirable to heat while pressing by a vacuum hot press. This is because the resin also flows into the via-holes and can reliably fill these through-holes.

Further, according to a fourth aspect of the present invention, there is provided a base substrate having an upper surface and a via erecting pad for erecting a via on the upper surface; an upper wiring layer; A pad wiring interposed between the pad and the upper wiring layer, and a via for connecting the via standing pad and the upper wiring layer, comprising a preformed wire,
A via embedded in the insulating layer between pad wirings,
It is a wiring board having.

According to the present invention, since the via is made of a preformed wire, the conductivity of the via can be made higher than when the via is formed by plating or the like. Further, since the strength is high, the via does not crack even if stress is applied to the via due to a difference in thermal expansion coefficient between the upper wiring layer and the base substrate or the insulating layer between pad wirings. Also,
To change the diameter of the via in consideration of conductivity and strength, it is sufficient to change the diameter of the wire.

Here, the material of the wire forming the via includes copper, copper alloy, silver, gold, aluminum, aluminum alloy and the like, and is selected in consideration of the material of the via standing pad and the upper wiring layer. Good to do. Examples of the material of the upper wiring layer include copper, silver, gold, nickel, and the like. Also, the material of the via-standing pad may be copper, silver, gold, nickel or the like. You may. Further, as a material of the insulating layer between pad wirings, a resin such as epoxy, polyimide, or BT, or a composite material of these resins with glass fiber, polymer fiber, or the like can be used.

The material of the base substrate may be appropriately selected from those having heat resistance capable of forming a via-standing pad on the upper surface thereof and resisting heating or the like when forming an insulating layer between pad wirings. I just need. Specifically, a substrate made of ceramics such as alumina and aluminum nitride,
Substrates made of a composite material such as glass epoxy are exemplified. In particular, it is preferable to use a ceramic base substrate because the rigidity of the entire wiring substrate is improved. In addition, when a wiring board is used in this base substrate,
Further, high-density wiring can be realized.

Further, according to a fifth aspect of the present invention, one end of a wire is fixed to a via-standing pad formed on an upper surface of a base substrate by a wire bonding method, and the wire is set at a predetermined height. Forming an erect via,
Placing the uncured insulator on the upper surface of the base substrate with the vias standing; heating and curing the uncured insulator to form an insulating layer between pad wirings; Leveling the upper surface of the insulating layer, exposing the top of the via, and forming an upper wiring layer connected to the exposed via on the upper surface of the inter-pad wiring insulating layer;
This is a method for manufacturing a wiring board having:

According to the present invention, a via using a wire formed in advance by a wire bonding method can be formed. Since the wire is formed in advance, the step of forming the wire by plating or the like as in the related art is not required, and a plating solution using various chemicals, a plating device, a cleaning device, and the like are not required, so that the wire can be formed at low cost. In addition, since a preformed wire is used, the via has high conductivity and high strength.

Here, as a method of erecting a wire on the via erecting pad by a wire bonding method, it is sufficient to form the wire by a known technique. For example, one end of the wire may be formed by thermocompression or ultrasonic compression. Adhere to the standing pad.

As a method of disposing the uncured insulator, when a resin paste is used, a method of applying the resin paste on the base substrate by a spray method, a calendar method, a spin coating method, or the like can be mentioned. That is, in the method of manufacturing a wiring board according to claim 5, the step of disposing the uncured insulator may be a step of applying a resin paste to the upper surface of the base substrate.
In this way, regardless of the arrangement of the standing wires,
The uncured insulator can be reliably disposed, and the work of forming a through-hole in the prepreg in advance becomes unnecessary.

As a method of arranging the uncured insulator, a prepreg having a through-hole (through-hole for via) provided at a position corresponding to a via which has been set up in advance is prepared so that the via penetrates the through-hole. Then, there is a method in which a prepreg is overlaid on the upper surface of the base substrate. That is, in the method of manufacturing a wiring board according to claim 5, the step of arranging the uncured insulating material includes a step of forming a prepreg having a through hole for a via at a position corresponding to the erected via in advance. It is good to be characterized by overlapping on the upper surface.

That is, one end of the wire is fixed to a via-standing pad formed on the upper surface of the base substrate by a wire bonding method, and the wire is erected at a predetermined height. Forming a via that has been formed, and disposing an uncured insulator in which a prepreg having a via hole formed in advance at a position corresponding to the via that has been erected is placed on the upper surface of the base substrate while the via is erected. A step of heating and curing the prepreg uncured insulating material to form an insulating layer between pad wirings, a step of adjusting the upper surface of the insulating layer between pad wirings, and exposing a top part of the via, Preferably, a method for manufacturing a wiring board, comprising: forming an upper wiring layer connected to the exposed via on the upper surface of the pad wiring insulating layer.

In this way, in addition to the functions and effects obtained by the fifth aspect of the present invention, the insulating layer between pad wirings can be easily formed only by laminating the base substrate and the prepreg and curing the prepreg. Can be formed. As described above, the prepreg includes a prepreg in which a resin paste is in a semi-cured state, and a prepreg in which fibers such as a glass nonwoven fabric are impregnated with a resin paste to be in a semi-cured state. In order to cure the prepreg, it is sufficient to simply heat it, but it is desirable to heat it while pressing it by a vacuum hot press. This is because the resin also flows into the via-holes and can reliably fill these through-holes.

[0065]

(Embodiment 1) A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a partially enlarged cross-sectional view for explaining a structure of a wiring board 100 according to the present embodiment. The wiring board 100 has three insulating layers in the vertical direction in the figure with respect to the metal plate 101 as a core substrate, and has three wiring layers. The metal plate 101 is made of copper and has an upper surface 101a.
A through hole 101h penetrating between the lower surface 101b and the lower surface 101b is formed at a predetermined position. Also, the upper surface 101 of the metal plate 101
A first insulating layer 103 and a second insulating layer 105 made of an epoxy resin are formed on the lower surface 101a and the lower surface 101b, respectively. I have.

The interlayer metal pillar 109 made of copper is
It is formed so as to penetrate the center of the through hole 101h, that is, the center of the in-hole insulating layer 107, and further penetrate the first and second insulating layers 103 and 105. Also, the metal pillar 109 for the interlayer
A plurality of first wiring layers 111 formed on the upper surface 103a of the first insulating layer 103 and lower surfaces 105b of the second insulating layer 105 A connection is made between a plurality of second wiring layers 112 formed thereon. Each of these wiring layers is made of copper.

Further, a first via 113 made of a copper wire is provided upright at a predetermined position of the first wiring layer 111, and an epoxy resin formed on the first insulating layer 103 and the first wiring layer 111 is formed. Embedded in the first interlayer insulating layer 115 made of. In addition, the first via 113
Wiring layer 111 and upper surface 115 a of first interlayer insulating layer 115
The third wiring layer 117 made of copper formed thereon is connected. Similarly, at a predetermined position of the second wiring layer 112,
A second via 114 made of a copper wire is provided upright, and is buried in a second interlayer insulating layer 116 formed on the second insulating layer 105 and the second wiring layer 112. The second via 114 is formed between the first wiring layer 112 and the fourth wiring layer 1 formed on the lower surface 116 b of the second interlayer insulating layer 116.
18 is connected.

Similarly, a third via 119 is provided upright at a predetermined position of the third wiring layer 117, and is formed in the third interlayer insulating layer 121 formed on the upper surface 115 a of the first interlayer insulating layer 115. Embedded in Also, the third via 1
Reference numeral 17 connects the third wiring layer 117 to the fifth wiring layer 123 formed on the upper surface 121a of the third interlayer insulating layer 121. Similarly, a fourth via 120 is provided upright at a predetermined position of the fourth wiring layer 118, and is embedded in the fourth interlayer insulating layer 122 formed on the lower surface 116 b of the second interlayer insulating layer 116. ing. Also, the fourth via 12
Numeral 0 connects the fourth wiring layer 118 to the sixth wiring layer 124 formed on the lower surface 122b of the fourth interlayer insulating layer 122.

In such a wiring board 100, the metal plate 101 is used as the central core board, and the glass-epoxy resin composite material or the like is not used as the core board as in the prior art. Does not occur. The interlayer metal pillar 109 is a copper wire formed in advance and is not formed in the through hole by plating.
I don't touch h. Therefore, even if the distance between the through-holes 101h (therefore, the interlayer metal pillars 109) is reduced, the insulation resistance does not decrease.

Furthermore, since the interlayer metal pillar 109 is a copper wire formed in advance, the conductivity is higher than that of, for example, a case where the interlayer metal pillar of the same size is formed by plating, and the first metal pillar 109 has the first conductivity. The wiring layer 111 and the second wiring layer 112 can be connected with low resistance. Furthermore, since it is a copper wire, it is dense and has high strength. Therefore, even if a stress or the like due to a difference in the coefficient of thermal expansion between the metal plate 101 and the first and second insulating layers 103 and 105 is applied to the interlayer metal pillar 109, a crack is not generated and it is not broken. Thus, the wiring board 100 having high reliability can be obtained.

In this wiring board 100, for example, when the first wiring layer 111 is a lower wiring layer and the third wiring layer 117 is an upper wiring layer, the first interlayer insulating layer 115 formed therebetween has The first wiring layer (lower wiring layer) 111 and the third wiring layer (upper wiring layer) 117 are connected to each other, and the first via layer 113 made of a wire is embedded therein.

Since the via 113 is also made of a copper wire formed in advance, the conductivity is higher than when, for example, a via of similar dimensions is formed by plating, and the first wiring layer 111 and the third wiring are formed. The layer 117 can be connected with low resistance. Further, copper wires are dense and have high strength.
Therefore, even if stress or the like due to a difference in the coefficient of thermal expansion between the first and third wiring layers 111 and 117 and the first interlayer insulating layer 115 and the like is applied to the via 113, a crack may occur and break. Therefore, the wiring board 100 can have high reliability. Note that a similar relationship is established between the second to fourth vias 11.
This is also true for 4,119,120.

Next, a method of manufacturing the wiring board 100 will be described. FIG. 2 to FIG. 4 are explanatory diagrams illustrating the manufacturing process of the wiring board 100. First, a metal plate 101 made of copper is prepared, and a through hole 101h is formed at a predetermined position as shown in FIG. Separately, a bottom plate H made of copper is prepared, one end of a wire made of copper is fixed to a position corresponding to the through hole 101h on the upper surface Ha by a wire bonding method, and further cut into a predetermined length to stand. The metal pillar standing body S including the interlayer metal pillar W0 is formed (see FIG. 2B). In this example, the tip of the copper wire was melted with a torch into a ball shape, and heated while being pressed against the bottom plate H with a capillary to fix the metal column W0 on the bottom plate upper surface Ha, as shown in FIG. 2 (b). In addition, the fixed portion W0h has a nail head (nail head) shape having a large diameter.

Note that the upper and lower surfaces 101a, 1
01b and the through-hole 101h, and the metal pillar W for interlayer
The surface of 0 is preferably roughened in order to improve the adhesion to the first and second insulating layers and the in-hole insulating layer to be formed later, and is a known method. , Blackening treatment,
Techniques such as micro-etching and needle-like Ni-Cu plating are mentioned. In this example, although not shown, a blackening process was used.

Next, the metal plate 101 and the metal pillar standing body S are combined. That is, first, an epoxy resin paste is applied to the bottom plate upper surface Ha of the metal pillar standing body S by spin coating, and further, the lower surface 10 of the metal plate 101 is further coated thereon.
1b and the bottom plate upper surface Ha so that they face each other.
Put 1 on. At this time, the metal pillars W0 for interlayer are arranged so as to pass through the through holes 101h. Further, the metal plate 10
The same epoxy resin paste is applied to the upper surface of 1 by spin coating.

In this manner, the through-hole 101h is filled with the epoxy resin paste. Then, by heating and curing the epoxy resin, a second insulating layer 105 'is formed between the lower surface 101b of the metal plate and the upper surface Ha of the metal plate, as shown in FIG. 2 (c). Metal plate upper surface 10
1a, a first insulating layer 103 'is formed. In the through-hole 101h, an in-hole insulating layer 107 is formed.
By doing so, the metal pillar W0 for the interlayer standing upright on the bottom plate H is buried in the first and second insulating layers 103 'and 105' and the in-hole insulating layer 107.

Thereafter, the bottom plate H is dissolved and removed by etching, and the upper surface of the first insulating layer 103 'and the lower surface of the second insulating layer 105' are polished to a predetermined thickness to form a surface. The upper and lower end surfaces of the metal pillar W0 are respectively exposed. As a result, as shown in FIG.
A first insulating layer 103 and a second insulating layer 105 are formed above and below the first insulating layer 103. Further, the end surfaces 109a and 109b penetrate the first and second insulating layers 103 and 105 and the in-hole insulating layer 107, respectively, and have the first insulating layer upper surface 103a and the second insulating layer lower surface 1 respectively.
Interlayer metal pillars 109 exposed from 05b are formed.
As described above, in the above steps, the plating method is not used, and the resin layer is not perforated with a drill or the like, so that the glass-epoxy resin composite material used as the core substrate as in the related art is used. Cracks are generated, and there is no fear that a plating solution or a cleaning solution permeates into the cracks.

Further, the first and second wiring layers 111 and 112 are formed on the first insulating layer upper surface 103a and the second insulating layer lower surface 105b by a subtractive method. That is, as shown in FIG. 3A, copper layers C1 and C2 are formed on the entire surface of the first insulating layer upper surface 103a and the second insulating layer lower surface 105b by electroless plating and electrolytic plating, respectively. The copper layers C1 and C2 are for forming first and second wiring layers to be described later.
1 and C2 are connected and conductive at end faces 109a and 109b, respectively.

Prior to forming the copper layers C1 and C2 (the first and second wiring layers 111 and 112), the first and second insulating layer upper surfaces 103a and 105b are roughened. And copper layers C1 and C2 (first and second wiring layers 11).
1,112) is preferably improved. Specifically, a known method includes a method of performing a roughening treatment using an oxidizing agent such as potassium permanganate or sodium permanganate. In this example, although not shown, roughening treatment was performed with sodium permanganate.

Next, etching resists D1 and D2 having a predetermined pattern are formed on the copper layers C1 and C2, respectively. Specifically, a photoresist is applied on the entire surface of the copper layers C1 and C2, and is exposed and developed to form an etching resist D.
1 and D2 are formed.

Thereafter, the exposed copper layers C1 and C2 are removed by etching, and the etching resists D1 and D2 are further removed.
2B, the first and second wiring layers 1 and 2 are formed on the first and second insulating layers 103 and 105, as shown in FIG.
11 and 112 are respectively formed. The first wiring layer 111 and the second wiring layer 112 are electrically connected via an interlayer metal pillar 109.

Further, the upper surface 111a of the first wiring layer 111
The first via 113 and the second via 1 are respectively formed at predetermined positions on the lower surface 112b of the second wiring layer 112 by using a wire made of copper by a wire bonding method.
14 is formed. That is, one end of a wire made of copper is fixed, and further cut to a predetermined length to be erected to form a via. In this example, the tip of the copper wire was melted with a torch to form a ball, and the wire was fixed by heating while pressing on the first and second wiring layers 111 and 112 with a capillary. As described above, the fixed portions 113h and 114h of the vias have a nail head shape. After that, the surfaces of the first and second wiring layers 111 and 112 and the surfaces of the vias 113 and 114 are preferably roughened in the same manner as described above. In this example, a blackening process was performed.

Then, on the first insulating layer upper surface 103a and the first wiring layer upper surface 111a, and on the second insulating layer lower surface
5b and the second wiring layer lower surface 112b, an epoxy resin paste is applied by a calendar coat method,
The second vias 113 and 114 are filled with a resin paste while standing upright. Further, the epoxy resin paste is cured by heating to form a first interlayer insulating layer 115 'and a second interlayer insulating layer 116'. As described above, since wires are used to form vias (first and second vias),
In the via manufacturing process, there is no need to go through a plating or cleaning process, and the via can be formed more reliably than in the case where the via is formed in the through hole having a small diameter by plating.

The first and second interlayer insulating layers 115 ', 11
The surface of 6 'is polished to a predetermined thickness, and is flattened as shown in FIG. Thereby, the first interlayer insulating layer 11
5. A second interlayer insulating layer 116 is formed. At this time, the top of each via, that is, the upper end 113a of the first via 113 and the lower end 114b of the second via 114 are connected to the first interlayer insulating layer upper surface 115a and the second interlayer insulating layer lower surface 116b, respectively.
To be exposed. Further, the first and second wiring layers 1
Similarly to the case where the first and second interlayer insulating layers 11 and 112 are formed, the surfaces of the upper and lower surfaces 115a and 116b of the first and second interlayer insulating layers are respectively roughened, and then the first interlayer insulating layer upper surface 115a and the second interlayer insulating layer are formed by a subtractive method. A third wiring layer 117 and a fourth wiring layer 118 are formed on the lower surface 116b of the two-layer insulating layer. Thus, for example, the first wiring layer 111 serving as a lower wiring layer and the third wiring layer 117 serving as an upper wiring layer are formed with the first interlayer insulating layer 115 interposed therebetween. The structure is such that the first via 113 is connected.

Similarly, third and fourth vias 119 and 120 are formed on the upper surface 117a of the third wiring layer and the lower surface 118b of the fourth wiring layer 118 by a wire bonding method, and the respective wiring layers and vias are blackened. Thereafter, further, on the first interlayer insulating layer upper surface 115a and the third wiring layer upper surface 117a,
Further, an epoxy resin is applied and cured on the second interlayer insulating layer lower surface 116b and the fourth wiring layer lower surface 118b to form the third and fourth interlayer insulating layers 121 'and 122' (FIG. 4B). reference). The third and fourth vias are formed below or above the first or second vias 113 and 1.
14 may or may not be located. For example, when the first via and the third via are formed by being stacked, a so-called stacked via structure is obtained. That is,
According to the present invention, a stacked via can be easily formed.

Next, the third and fourth interlayer insulating layers 121 ',
The surface of 122 ′ is polished and leveled to form third and fourth interlayer insulating layers 121 and 122 having a predetermined thickness.
21a, 122b to the top 119a, of the third and fourth vias.
120b is exposed (see FIG. 4C).

Then, similarly to the above-described first interlayer insulating layer and the like, the surfaces of the third and fourth insulating layers 121 and 122 are roughened, and the third interlayer insulating layer upper surface 121a and the second interlayer insulating layer 121 and 122 are formed by a subtractive method. The fifth and sixth wiring layers 123 and 124 were formed on the lower surface 122b of the four interlayer insulating layers, respectively, to complete the wiring board 100 shown in FIG. In the present embodiment, for example, a third wiring layer 117 serving as a lower wiring layer and a fifth wiring layer 123 serving as an upper wiring layer are formed with the third interlayer insulating layer 121 interposed therebetween. It has a structure in which one wiring layer is connected to a third via 119.

In the first embodiment, the first to sixth wiring layers are formed by the subtractive method. However, each wiring layer is formed by any method such as the semi-additive method and the full-additive method. May be formed.
That is, for example, according to the semi-additive method, an electroless plating layer is formed on the entire surface of the insulating layer (for example, the first insulating layer 103), and then a plating resist having a predetermined pattern is formed. Further, electrolytic plating is performed using the electroless plated layer as an electrode to raise the electrolytic plated layer on the exposed portion. Thereafter, the plating resist is removed, and the electroless plating layer exposed by the etching is removed to form a wiring layer having an independent pattern (for example, the first wiring layer 111).

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIGS. The wiring board 200 according to the present embodiment has a structure similar to that of the wiring board 100 (see FIG. 1) described in the first embodiment. The description will be centered, and similar parts will be omitted.

The metal plate 201 shown in FIG. 5A is the same as that used in the first embodiment,
It is a copper plate in which a through hole 201h penetrating between a and b is formed. On the other hand, the metal pillar standing body S ′ shown in FIG. 5B is different from the first embodiment in that the interlayer metal pillars made of wires are formed on the bottom plate H by wire bonding. The metal column W0 'is formed from an integral member. Specifically, the metal pillar standing body S 'is formed by etching a thick copper plate from one surface (the upper surface in the figure) while leaving the interlayer metal pillar W0'. In this way, a plurality of interlayer metal pillars W0 'can be formed at the same time, so that when a large number of interlayer metal pillars W0' are formed, the metal pillar standing body S 'can be easily formed. .

Note that, as in the first embodiment, the metal plate 201
The surface of the interlayer metal pillar W0 'is subjected to a blackening treatment as a roughening treatment. In the subsequent steps,
Blackening the via and the wiring layer is the same as in the first embodiment.

Next, as shown in FIG. 5 (c), the metal plate 201 and the metal pillar standing body S 'are combined. In this embodiment, plate-shaped first and second prepregs P1 and P2 in which through-holes (through-holes for metal pillars) P1h and P2h are drilled in advance at positions corresponding to the metal pillars W0 'for interlayer use, respectively. That is, first, the second prepreg P2 is overlaid on the upper surface Ha 'of the bottom plate H'. At this time, the interlayer metal pillar W0 'is made to penetrate the through hole P2h. Then, the metal plate 201
On the second prepreg P2, and further, the first prepreg P1. At this time, the through hole 201h and P1
h is formed so that the metal pillar for interlayer W0 'penetrates.

The first and second prepregs P1 and P2
Are made by impregnating a glass non-woven fabric with an epoxy resin paste into a semi-cured state, have a plate-like shape, and the epoxy resin is softened by heating, and then cured to form a glass fiber and an epoxy resin. It becomes a composite material.

After assembling in this manner, heating is performed while pressing in vacuum from above and below in the figure. Then, the epoxy resin in the first and second prepregs P1 and P2 softens and flows, and the inside of the through-hole 201h and the through-hole P1h,
Filled in P2h, then cured. As a result, in-hole insulating layers 207 made of epoxy resin are formed in the through-holes 201h. 205 is formed. Also, the metal column W0 '
In-hole insulating layer 207 and first and second insulating layers 203 and 205
It will be embedded in the.

When the first and second prepregs P1 and P2 are used, the through holes P1h and P2h need to be formed in advance. However, compared to the case where the resin paste described in the first embodiment is used, they are simply overlapped. , The process becomes easier. Another advantage is that it is easy to control the thickness of the insulating layer to a predetermined value. Further, in consideration of the strength and coefficient of thermal expansion of the wiring board, it is preferable to use a composite of glass fiber or the like and a resin (composite material). When a prepreg containing glass fiber or the like is used, it is convenient in that an insulating layer using such a composite material can be easily formed.

The prepreg has through holes (for example, P1
When perforating h), it is considered that a crack is generated between the glass fiber and the epoxy resin. However, even if cracks have occurred, the epoxy resin is actually softened by the subsequent heat treatment and adheres to the glass fibers. Therefore, problems such as cracks caused by drilling through holes in a prepreg state are caused. Does not occur.

Then, as in the first embodiment, the bottom plate H ′ is removed, and the upper surface 203 a of the first insulating layer 203 and the lower surface 205 b of the second insulating layer 205 are polished and leveled. The upper and lower surfaces 209a and 209b are exposed (see FIG. 5D).

Next, as in the first embodiment, the first insulating layer upper surface 203a and the second insulating layer lower surface 205b are
First and second wiring layers 211 and 212 are formed (FIG. 6A).
reference). Note that the first and second wiring layers may be formed by using a semi-additive method, a full-additive method, or the like in addition to the subtractive method. , 205b may be roughened,
This is the same as in the first embodiment. Further, the same applies to roughening the surface (upper and lower surfaces) of an insulating layer described later.

Further, as shown in FIG. 6B, first and second vias 213 and 214 made of copper wires are formed at predetermined positions of the first and second wiring layers 211 and 212 by a wire bonding method. Form. The first and second vias 21
The method for forming 1 and 212 is the same as in the first embodiment. Separately, through-holes (via through-holes) P3h and P4 are provided in advance at positions corresponding to the first and second vias 211 and 212, respectively.
The third and fourth prepregs P3 and P4 with h are prepared. The third prepreg P3 is inserted into the first wiring layer 21 such that the first via 211 is inserted into the through hole P3h.
Similarly, the fourth prepreg P4 is arranged on the lower surface 212b of the second wiring layer 212 such that the second via 212 is inserted into the through hole P4h. In addition, these prepregs P3 and P4 are also plate-like, and are made into a semi-cured state by impregnating a glass nonwoven fabric with an epoxy resin, similarly to the above-mentioned prepreg.

Thereafter, the third and fourth prepregs P3 and P4
Is heated while being pressed from above and below in a vacuum. Then, the epoxy resin in the prepreg softens and flows, and the through-hole P
3h and P4h, and the first and second wiring layers 211 and 211 are formed by flowing epoxy resin and deforming glass fibers.
Upper and lower surfaces 203a, 205 of the first and second insulating layers between 212
Epoxy resin or glass fiber is also buried in the portion where b is exposed, and is hardened. Thus, the first interlayer insulating layer 215 made of the glass-epoxy resin composite material is formed on the first insulating layer 203 and the first wiring layer 211. Further, a second interlayer insulating layer 2 made of a glass-epoxy resin composite material is formed on the second insulating layer 205 and the second wiring layer 212.
16 are formed. Also, the first and second vias 213 and 21
4 is embedded in the first and second interlayer insulating layers 215 and 216. The advantages of using the prepreg are the same as those of the prepregs P1 and P2.

Thereafter, as in the first embodiment, the upper surface 215a of the first interlayer insulating layer 215 and the second interlayer insulating layer 2
16, the lower surface 216b of the first via 213 is polished and leveled.
And the lower surface 214b of the second via 214 are exposed. Next, the first interlayer insulating layer upper surface 21
Third and fourth wiring layers 217 and 218 are formed on the lower surface 5a and the second interlayer insulating layer lower surface 216b by a subtractive method (see FIG. 6C). The third and fourth wiring layers 2
17, 18, 218 may be formed by using a semi-additive method, a full-additive method, or the like in addition to the subtractive method.

Thereafter, in the same manner as described above, the third and fourth vias 219 and 220, the third and fourth interlayer insulating layers 221 and 222 and the fifth and fourth vias 219 and 220 are formed by using a wire bonding method, a prepreg and a subtractive method. Sixth wiring layers 223, 22
By forming No. 4, a wiring board 200 having the same structure as that of the first embodiment (see FIG. 1) is completed (see FIG. 7). The wiring board 200 of the present embodiment is different from the wiring board 100 of the first embodiment.
The difference from the first and second insulating layers 203 and 205 and the first
The fourth to fourth insulating layers 215, 216, 221, 222 are made of a glass-epoxy resin composite material in which a glass nonwoven fabric and an epoxy resin are composited, instead of an epoxy resin.

In this embodiment, an example is shown in which a prepreg is used to form any of the insulating layers. However, for example, the first and second prepregs are used to form the first and second insulating layers. A resin paste may be used for forming the first and second interlayer insulating layers using P1 and P2, and vice versa. Alternatively, a prepreg may be used for forming the first insulating layer, and a resin paste may be used for forming the second insulating layer. The first and second insulating layers or the first and second interlayer insulating layers are used to prevent the wiring board from warping or bending by making the curing shrinkage and the coefficient of thermal expansion match as much as possible. As described above, it is preferable to use the same material for the insulating layers formed in pairs.

(Embodiment 3) Next, a third embodiment of the present invention will be described. The wiring board (not shown) in the present embodiment has the same structure as the wiring boards 100 and 200 (see FIGS. 1 and 5) described in the first and second embodiments, and is formed by the same method. . However, the metal plate 10 made of copper used for the core substrate in the first and second embodiments.
The difference is that a ceramic plate made of alumina ceramic (about 92% alumina) is used for the core substrate in place of 1,201. As described above, since the wiring board of the present embodiment uses a ceramic plate having high rigidity as the core substrate, the rigidity of the entire wiring board is increased, and the wiring board is less likely to be deformed by stress such as bending. Therefore, for example, even when an integrated circuit chip or the like is attached to a wiring board,
Inconveniences such as breakage of the flip chip connection portion are less likely to occur, and connection reliability can be improved.

It is needless to say that, unlike the first and second embodiments, the core substrate cannot be subjected to a roughening process (a blackening process or the like) because a ceramic plate is used as the core substrate. In this embodiment, an alumina ceramic plate is used as the core substrate. However, other ceramics, such as mullite, aluminum nitride, and glass ceramic, may be used. Further, a glass plate may be used, a resin plate such as an epoxy resin plate, or a composite material such as glass epoxy may be used. Note that when a composite material such as an epoxy resin plate or glass epoxy is used for the core substrate, the rigidity of the wiring substrate is lower than when a ceramic plate is used, but the thermal expansion of each insulating layer and the core substrate is reduced. Since the rate is an approximate value,
This is advantageous in that thermal stress is less likely to be applied to the interlayer metal pillars and vias.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG.
Has the same structure as the wiring board 100 (see FIG. 1) described in the first embodiment, and is formed by the same method. For this reason, the names and symbols (numbers) representing the respective parts are also described in the first embodiment.
Portions that do not change are described as the same.

However, in this embodiment, the upper and lower surfaces 101a and 101b of the metal plate 101 as the core substrate are
First and second core metal columns 40 each made of copper wire
2,403 are formed. Further, in FIG.
First and second wiring layers 111 and 11 formed two each on the left and right
2, the first and second wiring layers 11 formed on the left side in FIG.
1A, 112A and first and second core metal columns 402, 4
03 is different from the first embodiment in that they are connected to each other. Here, in the following, the first wiring layer formed on the left side in the figure is replaced with the first wiring layer 111A on the left side and the first wiring layer formed on the right side.
The wiring layers are distinguished from each other by the names on the left and right sides and the symbols A and B, as in the first wiring layer 111B on the right side. For this reason, in the present embodiment, the fifth and sixth wiring layers 12
5, 124 of the left side formed on the left side in FIG.
The wiring layers 123A and 124A conduct with the metal plate 101. On the other hand, the fifth and sixth wiring layers 123 on the right side in FIG.
B and 124B are insulated from the metal plate 101 as in the first embodiment.

In the wiring board 400 of the present embodiment thus configured, the metal plate 101 has a common potential over the entire surface of the wiring board 400. Therefore, the metal plate 101 can be connected to the left fifth wiring layer 123A or the left sixth wiring layer 123A.
For example, when the ground potential is set through the wiring layer 124A, that is, when the metal plate 101 is grounded, the first and second cores are provided at other positions where the ground potential is required, as shown in FIG. By using the metal pillars 402 and 403 for use, the ground potential can be easily taken out.
Conversely, the connection can be made at any place and the metal plate 101 can be easily connected.
Can be set to the ground potential. Moreover, the metal plate 1
Since 01 can be easily formed thicker than the wiring layer 111 and the like, it can be used as a ground plane which has a small self-inductance and a small resistance and hardly generates noise. Note that the metal plate 101 can be used as a signal wiring.

Further, the first and second core metal columns 402, 4
03 is connected to the first and second wiring layers 111A and 112A on the left side, both of which are connected to each other.
The two core metal pillars 403 are connected. This is because the metal plate 101 and a series of wirings (wiring layers 123A-111A-
112A-124A). Therefore, the number of the first and second core metal columns may be increased or decreased as necessary.

Next, a description will be given of a method of manufacturing the wiring board 400, focusing on parts different from the wiring board 100 of the first embodiment. In the present embodiment, as shown in FIG. 9A, the upper and lower surfaces 101 of the metal plate 101 are the same as in the first embodiment.
a and 101b, the first and second core metal columns 40, respectively.
2,403 are formed. In each of the core metal columns, a copper wire is erected at a predetermined position on the upper and lower surfaces 101a and 101b by a known wire bonding method. The height of each core metal column is, as described later,
It is preferable that the thickness be higher than the thickness of the first and second insulating layers 103 and 105 and lower than the thickness of the second insulating layer 105 ′.
The method of forming the first and second core metal pillars 402 and 403 is the same as that of the above-described wire bonding method, and the second embodiment.
In the same manner as above, the metal plate upper and lower surfaces 101a and 101
b, metal pillars 402, 40 for the core integrated with the metal plate 101;
3 may be formed.

Next, similarly to the first embodiment, the metal pillar standing body S shown in FIG. 9B is used, and the metal plate 101 and the metal pillar standing body S are connected as shown in FIG. 9C. Combination, insulation layer 1
03 'and 105' are formed. However, FIG. 9C is different in that first and second core metal columns 402 and 403 are formed.

Further, similarly to the first embodiment, the bottom plate H is removed, and the upper surface of the first insulating layer 103 'and the second insulating layer 10' are removed.
The lower surface of 5 ′ is trimmed to expose the upper and lower ends of the interlayer metal pillar 109. At this time, the first and second core metal columns 40
The upper and lower ends 402a and 403b of the 2,403 are also exposed (see FIG. 9D).

Next, in the same manner as in Embodiment 1, on the first insulating layer upper surface 103a and on the second insulating layer lower surface 105b,
The first and second wiring layers 111 and 1 are formed by a subtractive method.
12 is formed. That is, as shown in FIG.
Copper layers C1 and C2 are formed on the entire upper surface of the insulating layer upper surface 103a and the lower surface of the second insulating layer 105b, respectively. Next, etching resists D1 and D2 having a predetermined pattern are formed on the copper layers C1 and C2, respectively.

Thereafter, the exposed copper layers C1 and C2 are removed by etching, and the etching resists D1 and D2 are further removed.
2 is also removed to form the first and second wiring layers 1 on the first and second insulating layers 103 and 105, as shown in FIG.
11 and 112 are respectively formed. The first wiring layer 111 and the second wiring layer 112 are electrically connected via an interlayer metal pillar 109. In addition, the first and second core metal columns 4
02 and 403 are also left first and second wiring layers 111, respectively.
A, 112A. Therefore, the metal plate 10
1 is connected to the first and second wiring layers 111A and 112A on the left side. On the other hand, the first and second wiring layers 111 on the right side
B and 112B are insulated from the metal plate 101.

Further, as in the first embodiment, a predetermined position on the upper surface 111a of the first wiring layer 111 and the second wiring layer 11
2 at predetermined positions on the lower surface 112b of each of the first vias 1 by using a wire made of copper by a wire bonding method.
13 and the second via 114 are formed. Then, on the first insulating layer upper surface 103a and the first wiring layer upper surface 111a,
Also, the second insulating layer lower surface 105b and the second wiring layer lower surface 1
An epoxy resin paste is applied on 12b by a calendar coat method, and the first and second vias 113 and 114 are filled with the resin paste while standing. further,
The epoxy resin paste is cured by heating to form a first interlayer insulating layer 115 'and a second interlayer insulating layer 116' (see FIG. 10C). Thereafter, through the same steps as in the first embodiment, the wiring board 400 shown in FIG. 8 is completed.

According to the present embodiment, wires are also used for the first and second core metal columns 402 and 403 connecting the metal plate 101 and the first and second wiring layers 111A and 112A on the left side. Therefore, there is no need to go through a plating or cleaning step, and the wiring substrate 400 can be easily formed. Further, even the first and second core metal pillars 402 and 403 having a small diameter can be reliably formed.

(Embodiment 5) Next, a fifth embodiment of the present invention will be described with reference to FIGS. The wiring board 500 in the present embodiment shown in FIG. 11 is the same as the wiring boards 100 and 400 described in the first and fourth embodiments.
(See FIGS. 1 and 8), and is formed by a similar method. For this reason, the names and symbols (numbers) representing the respective parts are the same as those in the first embodiment.
The description is the same.

However, in the present embodiment, a glass-epoxy resin composite material (JIS: FR-4) is used for the core substrate 501 instead of the metal plate 101 made of copper used for the core substrate in the first and fourth embodiments. A difference is that a double-sided copper-clad insulating plate is used in which thin plates 501T and 501U made of copper are bonded to both surfaces of an insulating plate 501S. In addition, copper thin plate 50
1T is the first core metal pillar 50 in the left first wiring layer 111A of the two left and right first wiring layers 111 in FIG.
2, the copper thin plate 501U is connected to the right second wiring layer 11 of the two left and right second wiring layers 112.
2B via a second core metal column 503. For this reason, in the present embodiment, of the fifth and sixth wiring layers 123 and 124, the fifth and sixth wiring layers on the left are used.
The wiring layers 123A and 124A are electrically connected to the copper thin plate 501T, while the fifth and sixth wiring layers 123B and 124 on the right side.
B is electrically connected to the thin copper plate 501U.

In the wiring board 500 of the present embodiment thus configured, the two copper thin plates 501T, 501T,
U have a common potential over the entire surface of the wiring substrate 500. Therefore, the thin copper plate 501T is
Left fifth wiring layer 123A or left sixth wiring layer 124
A, for example, when the ground potential is set, that is, when the copper thin plate 501T is grounded and set as the ground plane, the first core is placed at another position where the ground potential is required, as shown in FIG. By using the metal column 502 for use, the ground potential can be easily taken out. Similarly, the copper thin plate 501U is connected to the right sixth wiring layer 12
For example, when the power supply potential is set to the power supply potential through 3B or the right sixth wiring layer 124B, that is, when the copper thin plate 501U is set to the power plane, as shown in FIG. By using the second core metal pillar 503, the power supply potential can be easily taken out. In addition, the copper thin plates 501T, U are
Since it can be formed to have a large area as compared with 11 or the like and can be easily formed to be thick, it can be used as a ground plane and a power plane which have a small self-inductance and a small resistance and are less likely to generate noise.

Further, when the copper thin plates 501T and 501U have different potentials, for example, as described above, the ground plane and the power plane, the copper thin plates 501T and 501U
U forms a capacitor having the insulating layer 501S as a dielectric layer. Therefore, this capacitor also makes it possible to efficiently remove noise that has entered the power supply or the ground potential. It is of course possible to use the copper thin plates 501T and U alone or only one of them as signal wiring.

In FIG. 11, the first and second core metal pillars 502 and 503 are formed one by one. However, the copper thin plates 501T and U and the first and second wiring layers 111 and 1 are formed.
Of course, in order to reduce the connection resistance with the core 12, a large number of core metal pillars may be formed and connected. Therefore, if necessary, the first and second core metal columns 502,
The number of 503 may be increased or decreased.

Next, a method of manufacturing the wiring board 500 will be described focusing on parts different from the wiring boards 100 and 400 of the first and fourth embodiments. In this embodiment, as shown in FIG. 12A, the core substrate 501 is a double-sided copper-clad insulating plate in which copper thin plates 501T and U are attached to both surfaces of an insulating plate 501S made of a glass-epoxy resin composite material. In addition, a through hole 501h is perforated as in the first embodiment. On the upper and lower surfaces 501a and 501b of the core substrate 501,
First and second core metal columns 502 and 503 are formed, respectively. Each of these metal pillars for the core is formed by bonding a copper wire to the upper and lower surfaces 501a, 501a by a known wire bonding method.
It is erected at a predetermined position 501b. Note that the height of each core metal column is higher than the thickness of the first and second insulating layers 103 and 105 and lower than the thickness of the second insulating layer 105 'before surface adjustment, as described later. And good.

Next, similarly to Embodiments 1 and 4, FIG.
Using the metal pillar standing body S shown in FIG. 12B, the core substrate 501 and the metal pillar standing body S are combined to form insulating layers 103 'and 105' as shown in FIG. 12C. However, in FIG. 12C, the first and second core metal columns 502,
503 is formed.

Further, similarly to the first and fourth embodiments, the bottom plate H
Is removed, the upper surface of the first insulating layer 103 ′ and the lower surface of the second insulating layer 105 ′ are leveled, and the upper and lower ends of the interlayer metal pillar 109 are exposed. At this time, the first and second core metal columns 5
Also, upper and lower end portions 502a and 503b of 02, 503 are exposed.

Then, in the same manner as in Embodiment 1, on the first insulating layer upper surface 103a and on the second insulating layer lower surface 105b,
The first and second wiring layers 111 and 1 are formed by a subtractive method.
12 is formed. That is, as shown in FIG.
Copper layers C1 and C2 are formed on the entire upper surface of the insulating layer upper surface 103a and the lower surface of the second insulating layer 105b, respectively. Next, etching resists D1 and D2 having a predetermined pattern are formed on the copper layers C1 and C2, respectively.

After that, the exposed copper layers C1 and C2 are removed by etching, and the etching resists D1 and D2 are further removed.
13B, the first and second wiring layers 1 and 2 are formed on the first and second insulating layers 103 and 105, as shown in FIG.
11 and 112 are respectively formed. The first wiring layer 111 and the second wiring layer 112 are electrically connected via an interlayer metal pillar 109. In addition, the first and second core metal columns 5
02 and 503 are also electrically connected to the left first wiring layer 111A and the right second wiring layer 112B, respectively. Therefore, the thin copper plate 501T is formed with the left first wiring layer 111A,
The thin copper plate 501U is connected to the right second wiring layer 112B.

Further, the upper surface 111a of the first wiring layer 111
The first via 113 and the second via 1 are respectively formed at predetermined positions on the lower surface 112b of the second wiring layer 112 by using a wire made of copper by a wire bonding method.
14 is formed. Next, an epoxy resin paste is applied on the first insulating layer upper surface 103a and the first wiring layer upper surface 111a, and on the second insulating layer lower surface 105b and the second wiring layer lower surface 112b by a calendar coating method. The second vias 113 and 114 are filled with the resin paste while standing. Further, the epoxy resin paste is cured by heating to form a first interlayer insulating layer 115 'and a second interlayer insulating layer 116' (see FIG. 13C).
Thereafter, through the same steps as in the first embodiment, the wiring substrate 500 shown in FIG. 12 is completed.

According to this embodiment, the copper thin plates 501T, U
Also, since the first and second core metal columns 502 and 503 connecting the first and second wiring layers 111 and 112 are also made of wires, there is no need to go through a plating or cleaning step, so that they can be easily performed. A wiring board can be formed. Further, even the first and second core metal columns 502 and 503 having a small diameter can be reliably formed.

In this embodiment, a double-sided copper-clad insulating plate using a glass-epoxy resin composite material as an insulating plate 501A is used as the core substrate 501. However, a composite material such as a glass-BT resin composite material or the like is used for the insulating plate 501S. And a resin plate such as an epoxy resin plate, or a ceramic such as alumina, mullite or aluminum nitride. Note that a composite material such as an epoxy resin plate or glass epoxy is used as the insulating plate 501S.
In this case, the thermal expansion coefficient of each insulating layer and the core substrate is an approximate value, so that thermal stress is less likely to be applied to each metal pillar, via, or the like. On the other hand, when ceramic is used for the insulating plate 501S, the rigidity of the wiring board 500 can be increased. Further, instead of a double-sided copper-clad insulating plate, a single-sided copper-clad insulating plate may be used. In this case, it goes without saying that the core metal pillar is also formed on the side where the copper plate is stretched.

(Embodiment 6) Next, a sixth embodiment of the present invention will be described with reference to FIGS. In each of the first to fifth embodiments, the wiring board in which the insulating layer and the wiring layer are formed substantially symmetrically in the vertical direction in the figure is shown. Shows a wiring layer and an insulating layer formed only on one surface of the substrate. Wiring board 600 according to the present embodiment shown in FIG.
Is based on a ceramic wiring substrate 650 as a base substrate, and two insulating layers 615, 621, 3
It has wiring layers 611, 617, and 623, and two-stage vias 613 and 619 connecting them.

The insulating layers 651 and 652 of the base substrate 650
Are made of an alumina ceramic containing alumina as a main component, are formed inside the substrate, and have insulating layers 651, 652.
Vias 661 and 662 penetrating through and internal wiring layer 67
No. 1 has tungsten as a main component and is formed by simultaneous firing. In addition, the base substrate 650
Is smoothed by polishing, and a first wiring layer 611 is formed thereon. The first wiring layer 611 is obtained by subjecting a sputtering layer laminated in the order of Ti / Mo / Cu to Cu plating.

Further, a first via 613 made of a copper wire is formed at a predetermined position on the first wiring layer 611 by a wire bonding method, and the first via 613 made of an epoxy resin is formed in the first interlayer insulating layer 615. Via 613 is embedded. Further, on the upper surface of the first interlayer insulating layer 615, Cu
A second wiring layer 617 made of plating is formed, and is connected to the first wiring layer 611 via the first via 613. Further, a second via 619 made of a copper wire is formed at a predetermined position of the second wiring layer 617 by a wire bonding method, and the second via 619 made of an epoxy resin is formed in the second interlayer insulating layer 621.
This second via 619 is buried. A third wiring layer 623 made of Cu plating is formed on the upper surface of the second interlayer insulating layer 621, and is connected to the second wiring layer 617 via the second via 619.

Therefore, the first wiring layer 611 and the second wiring layer 6
Focusing on the area between the first and second wiring layers, the first wiring layer 611 becomes a lower wiring layer, and the second wiring layer 617 becomes an upper wiring layer. In addition, a first interlayer insulating layer 615 is formed therebetween, and a first via 613 made of a wire and embedded in the first interlayer insulating layer 615 connects the lower wiring layer and the upper wiring layer. become. Note that the same relationship can be applied between the second wiring layer 617 and the third wiring layer 623.

Next, a method of manufacturing the wiring board 600 will be briefly described. First, as shown in FIG. 15A, a base substrate 650 made of an alumina ceramic wiring board having the above-described internal structure is formed by a known method.
Is formed, and the upper surface 650a is smoothed by polishing. Then, a Ti layer and a Mo layer are formed on substantially the entire upper surface 650a of the base substrate.
A layer and a Cu layer (both not shown) are deposited in this order by sputtering. Thereafter, a photoresist is applied, exposed and developed to form a predetermined pattern opening.
Cu electrolytic plating is performed using the i / Mo / Cu layer as a common electrode. Thereby, a Cu plating layer is formed in the opening. Thereafter, the photoresist is removed, and the exposed sputtered layers are removed by etching, so that Ti / Mo is removed.
Wiring layer 611 having layer structure of / Cu / Cu plating
Was formed. The layer structure and material of the first wiring layer 611 may be other materials, such as a Ti / Mo / Cu sputter layer + Ni / Au.
A first wiring layer having a layer configuration of electroless Cu plating + electrolytic Cu plating may be formed by a plating layer configuration, a subtractive method, or a semi-additive method.

Next, in the first embodiment, the first,
The second vias 113 and 114 and the first and second interlayer insulating layers 11
5, 116 in the same manner as the formation of the first via 613.
Then, a first interlayer insulating layer 615 is formed. First, a first via 613 is formed at a predetermined position on the upper surface of the first wiring layer 611 by using a wire made of copper by a wire bonding method. That is, one end of a wire made of copper is fixed, cut to a predetermined length, and erected to form a first via 613.

After that, an epoxy resin paste is applied on the upper surface 650a of the base substrate and the upper surface 611a of the first wiring layer by a calendar coating method, and the first via 613 is filled with the resin paste while standing upright. Further, by heating, the epoxy resin paste is hardened,
An interlayer insulating layer 615 'is formed. As described above, since the wire is used to form the via (first via), it is not necessary to go through a plating or cleaning step in the via manufacturing process.
The via can be formed more reliably than when the via is formed in the through hole having a small diameter by plating.

The surface of the first interlayer insulating layer 615 'is polished to a predetermined thickness, and is flattened to form a first interlayer insulating layer 615 as shown in FIG. At this time, the first
The upper end 613a of the via 613 is located on the first interlayer insulating layer upper surface 61.
Expose from 5a. Further, in the same manner as in the first embodiment, the upper surface 615a of the first interlayer insulating layer is roughened and the first interlayer insulating layer is formed by a subtractive method, similarly to the formation of the first and second wiring layers 111 and 112. Upper surface 6
The second wiring layer 617 is formed on 15a. Thus, the first wiring layer 611 serving as a lower wiring layer and the second wiring layer 617 serving as an upper wiring layer are formed with the first interlayer insulating layer 615 interposed therebetween. Via 6
13 are connected.

Thereafter, in the first embodiment, the third and fourth vias 119 and 120, the third and fourth interlayer insulating layers 121,
122, the second via 619, the second interlayer insulating layer 621, and the third wiring layer 623 are formed in the same manner as the formation of the fifth and sixth wiring layers 123 and 124, thereby completing the wiring substrate 600. Let it. As a result, the second wiring layer 617 serving as a lower wiring layer and the third wiring layer 623 serving as an upper wiring layer
Are formed with the second interlayer insulating layer 621 interposed therebetween.
A structure in which the two wiring layers are connected to the second via 619 is obtained.

The position where the second via 619 is formed is
As in the first embodiment, the first via 613 may be located at a position below or below the first via 613. Therefore,
By stacking the first via and the second via, a so-called stacked via structure can be easily formed. Since the wiring board 600 of the present embodiment uses a high-rigidity ceramic wiring board as the base substrate 650, the rigidity of the entire wiring board 600 is increased, and the wiring board 600 is not easily deformed by stress such as bending.
Therefore, for example, even when an integrated circuit chip or the like is attached to the wiring substrate 600, a problem such as breakage of a flip chip connection portion due to bending deformation or the like hardly occurs, and connection reliability can be increased. Further, the base substrate 6
Since a ceramic wiring board is used as 50, complicated and high-density wiring can be realized.

(Seventh Embodiment) Next, a seventh embodiment of the present invention will be described with reference to FIGS. This embodiment is similar to the sixth embodiment, and its manufacturing method is also similar. However, in the sixth embodiment, a ceramic wiring substrate is used as the base substrate 650, the wiring layer 611 is formed on the upper surface of the base substrate 650a, and the first via 613 is formed thereon. On the other hand, the present embodiment is different from the first embodiment in that a single-layer ceramic wiring board in which a number of vias for connecting upper and lower sides are formed is used, and a first via is formed on a pad formed above the via.

That is, the wiring substrate 700 of this embodiment shown in FIG. 16 uses a ceramic wiring substrate 750 as a base substrate, and has two insulating layers 71 on its upper surface 750a.
5, 721, two wiring layers 717 and 723, and two stages of vias 713 and 719. Base substrate 750
Has a single-layer insulating layer 751 made of alumina ceramic containing alumina as a main component. Upper and lower surfaces 7 of this insulating layer
Via 761 penetrating through holes 50a and 750b, and via-standing pad 77 covering via 761 with upper and lower surfaces 750a and 750b
Each of the pad 1 and the pad 772 has tungsten as a main component and is formed by simultaneous firing. Note that a Ni / Cu plating layer (not shown) is formed on the upper surface of the via standing pad 771 in this order.
On the upper surface 2, a Ni / Au plating layer (not shown) is formed in this order. However, via 77
1 is also replaced by Ni / Au instead of the Ni / Cu plating layer.
A plating layer may be formed.

Further, a first via 713 made of a copper wire is formed at a predetermined position on the via erecting pad 771 by a wire bonding method. Via 713 is embedded. A second wiring layer 717 made of Cu plating is formed on the upper surface of the inter-pad wiring insulating layer 715, and is connected to the via standing pad 771 via the first via 713. Further, a second via 719 made of a copper wire is formed at a predetermined position of the second wiring layer 717 by a wire bonding method, and the second via 719 is embedded in a second interlayer insulating layer 721 made of an epoxy resin. ing. A third wiring layer 723 made of Cu plating is formed on the upper surface of the second interlayer insulating layer 721, and the second via 71
9 and is connected to the second wiring layer 717.

Therefore, when attention is paid to the area between the via standing pad 771 and the second wiring layer 717, the second wiring layer 71
Reference numeral 7 denotes an upper wiring layer. In addition, via-standing pads 771
Between the second wiring layer 717 and the pad wiring insulating layer 71
5, the first via 713 made of a wire and embedded in the inter-pad wiring insulating layer 715 connects the via standing pad 717 and the second wiring layer (upper wiring layer) 717 become.

Next, a method of manufacturing the wiring board 700 will be briefly described. First, FIG.
A wiring board made of alumina ceramic having the above internal structure as shown in FIG.
A Ni / Cu plating layer is formed on the upper surface of the substrate 71. The reason why the Cu layer is provided on the upper surface of the via standing pad 771 is as follows.
This is for improving the connectivity in the bonding of the copper wire described later.

Next, in the first embodiment, the first,
The second vias 113 and 114 and the first and second interlayer insulating layers 11
5, via the first via 713
Then, a first interlayer insulating layer 715 is formed. First, the first via 713 is formed on the upper surface of the via standing pad 771 by using a wire made of copper by a wire bonding method.
That is, one end of a wire made of copper is fixed, cut to a predetermined length, and erected to form a first via 713.

Thereafter, an epoxy resin paste is applied on the upper surface 750a of the base substrate and the pads 771 for standing the vias by a calendar coat method, and is filled with the resin paste while the first vias 713 are standing. Further, by heating, the epoxy resin paste is cured to form a pad wiring insulating layer 715 '. As described above, since the wire is used to form the via (first via), it is not necessary to go through a plating or cleaning step in the via manufacturing process, and the via is formed by plating in the through hole having a small diameter. A via can be formed more reliably than in the case.

The surface of the pad-wiring insulating layer 715 'is polished to a predetermined thickness, and is flattened as shown in FIG. 17C to form the pad-wiring insulating layer 715. At this time, the upper end 713a of the first via 713 is exposed from the upper surface 715a of the inter-pad wiring insulating layer. Further, the upper surface 715 of the insulating layer between pad wirings is formed in the same manner as the first and second wiring layers 111 and 112 in the first embodiment.
After roughening a, a second wiring layer 717 is formed on the upper surface 715a of the inter-pad wiring insulating layer by a subtractive method. As a result, the via erecting pad 771 and the second wiring layer 717 serving as an upper wiring layer are formed with the inter-pad wiring insulating layer 715 interposed therebetween, and the via erecting pad and the upper wiring layer are separated from each other. This has a structure in which one via 713 is connected.

Thereafter, in the first embodiment, the third and fourth vias 119 and 120, the third and fourth interlayer insulating layers 121,
122 and the fifth and sixth wiring layers 123 and 124 in the same manner as the formation of the second via 719 and the interlayer insulating layer 72.
1 and the third wiring layer 723 are formed, and the wiring board 70 is formed.
Complete 0. Thus, the second wiring layer 717 serving as a lower wiring layer and the third wiring layer 723 serving as an upper wiring layer are formed with the interlayer insulating layer 721 interposed therebetween.
One wiring layer is connected to the second via 719.

The position where the second via 719 is formed is
As in the first and sixth embodiments, the first via 713 may or may not be located therebelow. Therefore, the so-called stacked via structure can be easily formed by stacking the first via and the second via. Since the wiring substrate 700 of the present embodiment uses a ceramic wiring substrate having high rigidity as the base substrate 750, the rigidity of the entire wiring substrate 700 is increased, and the wiring substrate 700 is not easily deformed by stress such as bending. Therefore, for example, even when an integrated circuit chip or the like is attached to the wiring substrate 700, a problem such as breakage of a flip chip connection portion due to bending deformation or the like hardly occurs,
Connection reliability can be improved.

In the fourth to seventh embodiments, the respective insulating layers are formed by applying an epoxy resin paste. However, as described in the second embodiment,
It goes without saying that each insulating layer may be formed using a composite material such as glass epoxy in which a glass nonwoven fabric is impregnated with an epoxy resin. In this case, as described in the second embodiment, it is preferable to form through holes in advance in accordance with the positions of the metal columns and vias.

In the above, the present invention is described with reference to Embodiments 1 to 7.
However, it is needless to say that the present invention is not limited to the above embodiment, and can be appropriately modified and applied without departing from the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view of a wiring board according to a first embodiment.

FIG. 2 is an explanatory diagram illustrating a process of exposing an interlayer metal pillar in the method of manufacturing a wiring board according to the first embodiment;

FIG. 3 is an explanatory diagram illustrating a process of embedding first and second vias in the method of manufacturing a wiring board according to the first embodiment;

FIG. 4 is an explanatory diagram illustrating a process of exposing third and fourth vias in the method of manufacturing a wiring board according to the first embodiment;

FIG. 5 is an explanatory diagram illustrating a process of exposing an interlayer metal pillar in the method of manufacturing a wiring board according to the second exemplary embodiment;

FIG. 6 is an explanatory diagram illustrating a process of forming a third and a fourth wiring layer in the method of manufacturing a wiring substrate according to the second embodiment.

FIG. 7 is a partially enlarged cross-sectional view of the wiring board according to the second exemplary embodiment.

FIG. 8 is a partially enlarged sectional view of a wiring board according to a fourth embodiment;

FIG. 9 is an explanatory diagram illustrating a process of exposing a metal pillar for an interlayer and a metal pillar for a core in the method of manufacturing a wiring board according to the fourth embodiment;

FIG. 10 is an explanatory diagram for explaining a process of embedding first and second vias in the method of manufacturing a wiring board according to the fourth embodiment;

FIG. 11 is a partially enlarged cross-sectional view of a wiring board according to a fifth exemplary embodiment.

FIG. 12 is an explanatory diagram illustrating a process of exposing a metal pillar for an interlayer and a metal pillar for a core in the method of manufacturing a wiring board according to the fifth embodiment;

FIG. 13 is an explanatory diagram illustrating a process of embedding first and second vias in the method of manufacturing a wiring board according to the fifth embodiment;

FIG. 14 is a partially enlarged cross-sectional view of a wiring board according to a sixth embodiment.

FIG. 15 is an explanatory diagram illustrating a process up to a step of forming a second wiring layer in the method of manufacturing a wiring board according to the sixth embodiment;

FIG. 16 is a partially enlarged sectional view of a wiring board according to a seventh embodiment;

FIG. 17 is an explanatory diagram for explaining the steps up to the step of forming the second wiring layer in the method of manufacturing the wiring board according to the seventh embodiment;

FIG. 18 is a partially enlarged cross-sectional view illustrating a structure of a conventional wiring board.

[Explanation of symbols]

100, 200, 300, 400, 500, 600, 7
00 Wiring board 101, 201 Metal plate 101h, 201h Through hole 103, 203 First insulating layer 105, 205 Second insulating layer 107, 207 In-hole insulating layer 109, 209 Interlayer metal pillar 111, 211 First wiring layer 112, 212 Second wiring layer 113,213 First via 114,214 Second via 115,215 First interlayer insulating layer 116,216 Second interlayer insulating layer 117,217 Third wiring layer 118,218 Fourth wiring layer 119,219 Third via 120, 220 Fourth via 121, 221 Third interlayer insulating layer 122, 222 Fourth interlayer insulating layer 123, 223 Fifth wiring layer 124, 224 Sixth wiring layer 402, 403, 502, 503 Metal pillar for core 501 Core substrate 650, 750 Base substrate 771 Via standing pad

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasunori Aoi 14-18 Takatsuji-cho, Mizuho-ku, Nagoya-shi, Aichi Prefecture Inside Nihon Tokusui Tougyo Co., Ltd. No. 18 Japan Special Ceramics Co., Ltd.

Claims (6)

[Claims] A lower wiring layer, an upper wiring layer, an interlayer insulating layer interposed between the lower wiring layer and the upper wiring layer, and a via connecting the lower wiring layer and the upper wiring layer. And a via made of a wire formed in advance and embedded in the interlayer insulating layer. 2. A via is formed at a predetermined position on an upper surface of a lower wiring layer formed on a lower insulating layer by wire bonding, with one end of the wire fixed and the wire standing upright at a predetermined height. A step of disposing an uncured insulator on the upper surface of the lower insulating layer and the upper surface of the lower wiring layer with the vias standing; heating the cured uncured insulator to form an interlayer insulating layer; A step of trimming the upper surface of the interlayer insulating layer and exposing the top of the via; and a step of forming an upper wiring layer connected to the exposed via on the upper surface of the interlayer insulating layer; A method for manufacturing a wiring board having: 3. A via is formed at a predetermined position on an upper surface of a lower wiring layer formed on a lower insulating layer by wire bonding, with one end of the wire fixed and the wire standing upright at a predetermined height. A step of stacking a prepreg having a through hole for a via in advance at a position corresponding to the via which has been erected on the upper surface of the lower insulating layer and the upper surface of the lower wiring layer while the via is erected; Curing the prepreg to form an interlayer insulating layer, leveling the upper surface of the interlayer insulating layer and exposing the top of the via, and forming the exposed via on the upper surface of the interlayer insulating layer. Forming an upper wiring layer to be connected. 4. A base substrate having an upper surface and a via erecting pad for erecting a via on the upper surface, an upper wiring layer, and between the via erecting pad and the upper wiring layer. An intervening pad-wiring insulating layer, a via connecting the via-erecting pad and the upper wiring layer, the via being made of a preformed wire, and embedded in the pad-wiring insulating layer. And a wiring board having the same. 5. A step of fixing one end of a wire to a via-standing pad formed on an upper surface of a base substrate by a wire bonding method, and forming a via with the wire standing at a predetermined height. A step of disposing an uncured insulator on the upper surface of the base substrate with the vias standing; a step of curing the uncured insulator by heating to form an insulating layer between pad wirings; A step of trimming an upper surface of an insulating layer to expose a top portion of the via; and a step of forming an upper wiring layer connected to the exposed via on the upper surface of the insulating layer between pad wirings. Production method. 6. A step of fixing one end of a wire to a via-standing pad formed on an upper surface of a base substrate by a wire bonding method, and forming a via with the wire standing at a predetermined height. A step of superposing a prepreg having a through hole for a via at a position corresponding to the via erected beforehand on the upper surface of the base substrate while the via is erected; heating the prepreg to cure the prepreg; Forming an insulating layer; adjusting the upper surface of the inter-pad wiring insulating layer to expose the top of the via; and forming an upper wiring layer connected to the exposed via on the upper surface of the inter-pad wiring insulating layer. Forming a wiring board.