JP2003282779A - Multilayer wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer wiring board composed of a board and an insulating film layer formed on the board, wherein a wiring conductor layer and a through conductor are prevented from being separated from each other in a heating process carried out when a chip component is mounted or in an environmental resistance test such as a thermal cycle test. <P>SOLUTION: A plurality of insulating layers of organic resin and wiring conductor layers 3 are laminated in multilayer and bonded together on a board 1, and the upper wiring conductor layers 3 and the lower wiring conductor layers 3 are electrically connected together by the through conductors 7 each provided in a through-hole 6 bored in the insulating layer located between the wiring conductor layers 3 for the formation of the multilayer wiring board. At least one of the through conductors 7 located on the wiring conductor 3 on the peripheral surface of the board 1 is made to function as a large through conductor 8 larger in cross sectional area than the other through conductors 7. By this setup, stress imposed on the other through conductors 7 is relaxed by the large through conductor 8, so that the wiring conductor layer 3 is hardly separated from the bottom of the through conductor 7. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer wiring board, and more particularly to a multilayer wiring board used for a hybrid integrated circuit device and a semiconductor element housing package for housing semiconductor elements.

[0002]

2. Description of the Related Art Conventionally, as a multilayer wiring board used for a hybrid integrated circuit device, a package for accommodating semiconductor elements, etc.
For the purpose of forming the wiring conductors at a high density, a multilayer wiring board in which a multilayer wiring portion including a thin insulating layer and a wiring conductor layer is formed on the substrate has been adopted.

Such a multilayer wiring board comprises a thin film insulating layer made of a polyimide resin or the like formed by a spin coating method or the like on the upper surface of a substrate made of an aluminum oxide sintered body or the like, and a metal such as copper or aluminum. It has a structure in which a wiring conductor layer formed by adopting a thin film forming technique such as a plating method or a vapor deposition method and a photolithography technique are alternately laminated in multiple layers.

However, when an insulating layer made of a polyimide resin is formed by a spin coating method, it is necessary to apply the polyimide resin precursor in a number of times in order to form the insulating layer with a desired thickness. In addition, there is a problem that the manufacturing process becomes long because a curing process for polyimidizing the precursor of the polyimide resin is required.

Therefore, a multilayer wiring board using an insulating layer formed by laminating a plurality of insulating film layers made of polyimide resin or the like with an insulating adhesive layer made of bismaleimide triazine resin or the like interposed therebetween has been adopted. .

In order to form an insulating layer in such a multilayer wiring board, first, an insulating film is coated with an insulating adhesive by a doctor blade method or the like and dried to prepare an insulating film layer, which is used to insulate a substrate or a lower layer. It is carried out by stacking the insulating adhesive layer on the upper surface of the film layer so as to be disposed between them, and heating and pressurizing this by using a heating press device to bond them.

For electrical connection between the wiring conductor layers located above and below, through holes are formed in the insulating film layer and the insulating adhesive layer by a method such as laser or dry etching,
After that, a through conductor is formed on the inner wall of the through hole by a vacuum film forming method or a plating method.

These are formed by a manufacturing method including the following steps (1) to (5). (1) Form a rectangular or circular through hole in the insulating film layer and the insulating adhesive layer by laser or plasma,
The inside is roughened with a roughening liquid such as a potassium permanganate solution. (2) Pd or the like is applied as a plating catalyst to the roughened surface, and then a base conductor film is formed by electroless plating. (3) Next, a photoresist is applied on the underlying conductor film, and the photoresist is exposed and developed to form a window portion having a predetermined shape in a portion of the underlying conductor layer where the upper main conductor layer is formed. To do. (4) Next, an electrolytic plating film having a thickness of 3 to 10 μm is formed using the underlying conductor layer exposed in the window portion of the photoresist as an electrode. As a result, a plating film is formed on the exposed underlying conductor layer corresponding to the portion of the upper main conductor layer, and the plating film is not formed on the other portions because it is covered with photoresist. The main conductor layer is formed only on the portion corresponding to the through conductor. (5) After the main conductor layer having a predetermined thickness is formed in this manner, the photoresist is peeled and removed, and then the main conductor layer is used as an etching resist for the base conductor layer previously used as the electrode for electrolytic plating. By etching a part, the upper wiring conductor layer and the through conductor are formed.

[0009]

However, in a multilayer wiring board in which the insulating film layers as described above are heated and pressed through an insulating adhesive layer to bond them, the substrate, the through conductor, the insulating film layer, the insulating The coefficient of thermal expansion differs depending on the material of each adhesive layer, so it may be partially heated by the heating process when mounting chip parts etc. on the multilayer wiring board or the heating / cooling of environment resistance test such as temperature cycle test. The stress is concentrated on.

For example, the stress due to the difference in thermal expansion between the substrate, the insulating adhesive layer, and the insulating film layer is applied to the respective interfaces, in particular, the interface between the substrate and the insulating adhesive layer, which differ greatly in material, and further to the outer peripheral portion of the substrate. Greater stress will be generated in the vicinity. Therefore, due to the concentration of these stresses, the point where the through hole is in contact with the upper surface of the wiring conductor layer immediately above the substrate surface, particularly near the outer peripheral portion of the substrate,
At the interface between the wiring conductor layer and the through conductor, when the adhesive force at the interface is low, a crack occurs in the interface direction, and there is a problem that the wiring conductor layer and the through conductor are separated.

The present invention has been made in view of the above problems in the prior art, and its object is to be generated by thermal stress in a heating process when mounting a chip component or the like, or in an environmental resistance test such as a temperature cycle test. It is an object of the present invention to provide a multilayer wiring board which is excellent in electrical connection reliability and which suppresses peeling between a wiring conductor layer and a through conductor.

[0012]

A multilayer wiring board according to the present invention has a structure in which a plurality of insulating film layers made of organic resin and a wiring conductor layer are formed on the substrate in multiple layers with an insulating adhesive layer interposed between the insulating film layers. A multilayer wiring board which is laminated and adhered, and the wiring conductor layers located above and below are electrically connected by arranging through conductors in through holes provided in the insulating film layer and the insulating adhesive layer therebetween. Of the through conductors, at least a part of the through conductors arranged on the wiring conductor layer disposed on the surface of the substrate in the outer peripheral portion of the substrate has a larger cross-sectional area than other through conductors. It is characterized by being a through conductor.

Further, in the multilayer wiring board of the present invention, in the above-mentioned constitution, the large-diameter through conductor has the insulating film layer and the insulating adhesive layer from the lowermost layer to the upper layer of the insulating adhesive layer and the insulating adhesive layer. It is characterized in that the insulating adhesive layer is continuously arranged vertically.

Further, the multilayer wiring board of the present invention is characterized in that, in the above structure, a portion of the large-diameter through conductor arranged in the upper layer has a smaller cross-sectional area than a portion arranged in the lowermost layer. It is a thing.

Further, the multilayer wiring board of the present invention is characterized in that, in each of the above-mentioned constitutions, the bottom surface of the large-diameter through conductor is embedded in the board together with the wiring conductor layer.

According to the multilayer wiring board of the present invention, at least a part of the through conductors arranged on the wiring conductor layer provided on the surface of the substrate at the outer peripheral portion of the substrate is more than that of the other through conductors. Since it is a large-diameter through-conductor with a large cross-sectional area, the large-diameter through-conductor on the outer peripheral portion of the substrate is subject to thermal stress generated in environment resistance tests such as heating processes and temperature cycle tests when mounting chip components, etc. Is concentrated and supported, so that no stress that would break the other through conductors is applied. For this reason, no crack is generated in the interface direction between the wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. As a result, the occurrence of conduction failure between the upper and lower wiring conductor layers is eliminated, and the multilayer wiring board has excellent electrical connection reliability.

Further, according to the multilayer wiring board of the present invention, the large-diameter through conductors are vertically arranged from the lowermost layer of the insulating film layer and the insulating adhesive layer on the substrate side to the upper insulating film layer and the insulating adhesive layer. When they are arranged consecutively,
The large-diameter through conductors on the outer periphery of the substrate of each layer concentrate and support the thermal stress of each layer that occurs in the environmental resistance test such as the heating process and temperature cycle test when mounting chip parts. Therefore, the other through conductor of each layer is not subjected to a stress such as breaking. Therefore, no crack is generated in the interface direction between each wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. As a result, the occurrence of conduction failure between the upper and lower wiring conductor layers is eliminated, and the multilayer wiring board has more excellent electrical connection reliability.

Further, according to the multilayer wiring board of the present invention,
When the area of the large-diameter through conductor arranged in the upper layer has a smaller cross-sectional area than the area of the lowermost layer, the stress of each layer becomes smaller as the large-diameter through conductor arranged in this upper layer goes from the substrate side to the upper layer. By forming the large-diameter through conductors in a cross-sectional area corresponding to the above, it is possible to reduce the occupied area in each layer of the large-diameter through-conductors as compared with the case where the large-diameter through conductors are continuously arranged vertically with the same cross-sectional area. Therefore, it becomes possible to cope with the high density of the wiring conductor layer. As a result, a multi-layer wiring board with excellent electrical connection reliability, in which the occurrence of conduction failure between the wiring conductor layers located above and below can be eliminated and the wiring conductor layers can be formed at high density.

Further, according to the multilayer wiring board of the present invention,
When the bottom surface of the large-diameter through conductor is embedded in the board together with the wiring conductor layer, the thermal stress generated in the environment resistance test such as the heating process or the temperature cycle test when mounting the chip parts etc. Even when concentrated on a large-diameter through conductor, the stress concentrated on the interface direction between the wiring conductor layer and the through-conductor can be dispersed from the bottom surface of the large-diameter through conductor to the sidewall direction. The adhesive strength with the through conductor becomes stronger, and the stress that causes the other through conductor to break is more reliably not applied. For this reason, no crack is generated in the interface direction between the wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. This eliminates the occurrence of conduction failure between the upper and lower wiring conductor layers,
The multilayer wiring board has even more excellent electrical connection reliability.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The multilayer wiring board of the present invention will be described in detail below with reference to the drawings.

1 to 3 are cross-sectional views showing an example of an embodiment of a multilayer wiring board of the present invention, and FIG. 4 is a bottom layer on the substrate side in an example of an embodiment of a multilayer wiring board of the present invention. 3 is a top view showing the insulating film layer of FIG. In these figures, 1 is a substrate, 2 is a multilayer wiring part, 3 is a wiring conductor layer, 4 is an insulating film layer, 5 is an insulating adhesive layer, 6 is a through hole, 7 is a through conductor, and 8 is a large-diameter through hole. It is a conductor.

The substrate 1 is provided with a multilayer wiring section 2 in which a plurality of insulating film layers 4 are laminated on the upper surface of the substrate 1 with an insulating adhesive layer 5 interposed therebetween and a wiring conductor layer 3 are laminated in multiple layers. And functions as a support member that supports the multilayer wiring section 2.

The substrate 1 is an oxide ceramic such as an aluminum oxide sintered body or a mullite sintered body, or an aluminum nitride sintered body having an oxide film on its surface, a silicon carbide sintered body, or silicon nitride. Electricity of non-oxide ceramics such as high quality sintered body, glass epoxy resin impregnated with glass fiber base material, glass fiber base material impregnated with bismaleimide triazine resin, etc. It is made of an insulating material.

For example, when it is formed of an aluminum oxide sintered body, an appropriate organic solvent or solvent is added to and mixed with a raw material powder of alumina, silica, calcia, magnesia, etc. to form a slurry. A ceramic green sheet (ceramic green sheet) is formed by adopting the conventionally well-known doctor blade method or calendar roll method, and then this ceramic green sheet is subjected to appropriate punching processing to form a predetermined shape and high temperature (about The raw material powder is prepared by firing at 1600 ° C) or by adding and mixing an appropriate organic solvent or solvent to the raw material powder such as alumina, and the raw material powder is molded into a predetermined shape by a press molding machine. It is manufactured by firing a compact at a high temperature (about 1600 ° C).

When it is made of glass epoxy resin, it is manufactured by impregnating a base material made of glass fiber, for example, with a precursor of epoxy resin and thermally curing the epoxy resin precursor at a predetermined temperature.

On the upper surface of the substrate 1, there is provided a multi-layer wiring section 2 in which a plurality of insulating film layers 4 are laminated with an insulating adhesive layer 5 interposed therebetween and a wiring conductor layer 3 are laminated in multiple layers. Has been done. The insulating film layer 4 forming the multilayer wiring portion 2 electrically insulates the wiring conductor layers 3 located above and below, and the wiring conductor layer 3 functions as a transmission path for transmitting an electric signal.

The insulating layer of the multilayer wiring part 2 is an insulating film layer 4
And an insulating adhesive layer 5, and an insulating film layer 4
Is polyimide resin, polyphenylene sulfide resin,
Consists of wholly aromatic polyester resin, fluororesin, etc. The insulating adhesive layer 5 is made of polyamide-imide resin, polyimide-siloxane resin, bismaleimide-triazine resin,
It is made of epoxy resin.

The insulating layer is prepared by first coating an insulating film having a thickness of about 12.5 to 50 μm with an insulating adhesive to a dry thickness of about 5 to 20 μm by using a doctor blade method or the like and drying the insulating film. It is formed by stacking the insulating adhesive on the upper surfaces of the substrate 1 and the lower insulating layer so that the insulating adhesive is disposed between them, and heating and pressurizing the insulating adhesive using a heating press device to bond them.

Among them, in the combination in which the through conductor 7 is made of copper or copper alloy, the insulating film layer 4 is made of polyimide resin, and the insulating adhesive layer 5 is made of polyimide siloxane resin or siloxane modified polyamide imide resin, polyimide siloxane is used. The resin or the siloxane-modified polyamide-imide resin has good adhesiveness with the insulating film layer 4, has high heat resistance, and has a thermal expansion coefficient relatively close to that of copper, so that the thermal expansion difference between the through conductor 7 and the insulating layer is also high. Get smaller.

A through hole 6 penetrating the insulating film layer 4 and the insulating adhesive layer 5 is formed at a predetermined position in the insulating layer, and a through conductor 7 is formed in the through hole 6 by adhesion. Thus, a connection path for electrically connecting each of the wiring conductor layers 3 located above and below the insulating film layer 4 is formed.

The through holes 6 are formed by removing a part of the insulating film layer 4 and the insulating adhesive layer 5 by using, for example, a laser. In particular, when the opening diameter of the through hole 6 is small, it is desirable to form the inner wall surface of the through hole 6 by an ultraviolet laser that can easily control the angle of the inner wall surface of the through hole 6 and can be processed smoothly.

The wiring conductor layer 3 disposed on the upper surface of each insulating film layer 4 and the through conductor 7 and the large diameter through conductor 8 disposed in the through hole 6 are made of copper, gold, aluminum, nickel, chromium, molybdenum. , Titanium and alloys thereof can be formed by adopting thin film forming techniques such as sputtering, vapor deposition, and plating.

The through conductor 7 may be formed separately from the wiring conductor layer 3, but if they are formed at the same time, the number of steps can be reduced and the electrical connection reliability between the two is good. When the wiring conductor layer 3 and the penetrating conductor 7 are integrally formed by a plating method, they are formed mainly by the electrolytic plating method so that a plating film having a desired thickness can be adjusted and formed for each. It's good to do.

At this time, as shown in FIGS. 1 and 4,
At least a part of the through conductors 7 arranged on the wiring conductor layer 3 provided on the surface of the substrate 1 in the outer peripheral portion of the substrate 1 has a large cross-sectional area larger than other through conductors 7. It is better to set it to 8. The large-diameter through conductors 8 are arranged on the outer peripheral portion of the substrate 1. For example, when the substrate 1 is a quadrangle, disposing one at each of the four corners ensures the effect of the present invention. And it can be obtained efficiently. In addition, a plurality of large-diameter through conductors 8 are provided along the four sides.
May be arranged so as to surround the other through conductor 7. Further, when the substrate 1 has a circular shape, it is advisable to dispose one at each of the corners of the apexes of the regular polygon inscribed therein.

Further, the large-diameter through conductor 8 is formed on the substrate 1 of the insulating film layer 4 and the insulating adhesive layer 5 as shown in FIG.
It is preferable that the uppermost insulating film layer 4 and the upper insulating film layer 5 are continuously arranged in the vertical direction.
When the large-diameter through conductors 8 are continuously formed vertically, it is best to make them linearly continuous, but the effect of the present invention can be obtained even if they are formed slightly offset. However, in that case, it is preferable that at least 25% or more of the cross-sectional area of the large-diameter through conductor 8 is overlapped.

Further, it is preferable that the portion arranged in the upper layer of the large-diameter through conductor 8 has a smaller cross-sectional area than that of the portion arranged in the lowermost layer, whereby the occupied area of the large-diameter through conductor 8 is minimized. It is desirable for the multilayer wiring board that the wiring conductor layer 3 is densified so that the density can be increased.

The extent to which the cross-sectional area of the large-diameter through conductor 8 arranged in the upper layer is made smaller than that of the large-diameter through conductor 8 arranged in the lowermost layer depends on the requirement for the density of the wiring conductor layer 3 and the heat which becomes smaller as it goes up. It may be appropriately set in consideration of the magnitude of stress, etc., and in a state where the cross-sectional area of the large-diameter through conductor 8 arranged in the uppermost layer is larger than the cross-sectional areas of the other through conductors 7,
For example, it may be set so as to be gradually reduced.

Further, as shown in FIG. 3, the bottom surface of the large-diameter through conductor 8 provided on the surface of the substrate 1 has a recess formed in the substrate 1 and is embedded in the recess together with the wiring conductor layer 4. It is preferable to keep the large-diameter through conductor 8 on the substrate 1
It can be firmly fixed to the substrate, and the reliability can be further improved. If the depth of the recess is shallower than 1 μm, the stress is not sufficiently dispersed, and cracks are likely to occur at the bonding interface. Therefore, when the bottom surface of the large-diameter through conductor 8 is embedded in the surface of the substrate 1, the depth of the embedded portion is preferably 1 μm or more.

The wiring conductor layer 3, the through conductor 7, and the large-diameter through conductor 8 may be formed by the following method, for example. First, a copper layer is mainly formed in a wide area, and chromium, molybdenum, titanium or the like as a diffusion prevention layer (barrier layer) is deposited on at least one main surface of the copper layer to form a base conductor layer. Next, a photoresist is formed in a desired pattern on this, and the main conductor layer portion is formed by plating to a desired thickness using this photoresist as a mask. After that, the photoresist is peeled off and the underlying conductor layer is removed by etching to form a desired pattern, thereby forming the desired wiring conductor layer 3, the through conductor 7, and the large-diameter through conductor 8.

It should be noted that the uppermost main conductor layer of the insulating film layer 4 has the following characteristics in terms of mountability of chip components and environmental resistance.
When the main conductor layer is made of a copper layer, it is preferable to form a nickel layer or a gold layer on it in order to prevent oxidation of the surface or to prevent an increase in resistance value due to oxidation.

Thus, in the multilayer wiring board of the present invention, electronic components such as a semiconductor element, a capacitive element, and a resistor are mounted and mounted on the multilayer wiring section 2 attached to the upper surface of the substrate 1, and each electronic component is mounted. By electrically connecting the electrodes to the wiring conductor layer 3, a semiconductor device, a hybrid integrated circuit device or the like is obtained.

The present invention is not limited to the examples of the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above-mentioned example, the opening of the through hole 6 is performed for each formation of the insulating film layer 4 and the insulating adhesive layer 5, but after forming all the insulating layers, the uppermost layer to the lowermost layer are collectively formed. The through hole 6 may be opened and the large-diameter through conductor 8 may be arranged therein.

[0043]

As described above, according to the multilayer wiring board of the present invention, at least a part of the through conductors arranged on the wiring conductor layer provided on the surface of the board in the outer peripheral portion of the board is formed. Since it is a large-diameter through conductor that has a larger cross-sectional area than other through conductors, the thermal stress generated in the environment resistance test such as the heating process or temperature cycle test when mounting chip parts etc. Since the large-diameter through conductors in the portion are supported in a concentrated manner, the other through conductors are not subject to stress such as breaking. For this reason, no crack is generated in the interface direction between the wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. This eliminates the occurrence of conduction failure between the upper and lower wiring conductor layers,
The multilayer wiring board has excellent electrical connection reliability.

Further, according to the multilayer wiring board of the present invention,
When the large-diameter through conductors are continuously arranged vertically from the lowermost layer on the substrate side of the insulating film layer and the insulating adhesive layer to the upper insulating film layer and the insulating adhesive layer, chip components, etc. are mounted. The large-diameter through conductors on the outer periphery of the substrate of each layer concentrate and support the thermal stress of each layer generated in the environmental resistance test such as the heating process and the temperature cycle test. The through conductor is not stressed so as to break. Therefore, no crack is generated in the interface direction between each wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. As a result, the occurrence of conduction failure between the upper and lower wiring conductor layers is eliminated, and the multilayer wiring board has more excellent electrical connection reliability.

Further, according to the multilayer wiring board of the present invention,
When the area of the large-diameter through conductor arranged in the upper layer has a smaller cross-sectional area than the area of the lowermost layer, the stress of each layer becomes smaller as the large-diameter through conductor arranged in this upper layer goes from the substrate side to the upper layer. By forming the large-diameter through conductors in a cross-sectional area corresponding to the above, it is possible to reduce the occupied area in each layer of the large-diameter through-conductors as compared with the case where the large-diameter through conductors are continuously arranged vertically with the same cross-sectional area. Therefore, it becomes possible to cope with the high density of the wiring conductor layer. As a result, a multi-layer wiring board with excellent electrical connection reliability, in which the occurrence of conduction failure between the wiring conductor layers located above and below can be eliminated and the wiring conductor layers can be formed at high density.

Further, according to the multilayer wiring board of the present invention,
When the bottom surface of the large-diameter through conductor is embedded in the board together with the wiring conductor layer, the thermal stress generated in the environment resistance test such as the heating process or the temperature cycle test when mounting the chip parts etc. Even when concentrated on a large-diameter through conductor, the stress concentrated on the interface direction between the wiring conductor layer and the through-conductor can be dispersed from the bottom surface of the large-diameter through conductor to the sidewall direction. The adhesive strength with the through conductor becomes stronger, and the stress that causes the other through conductor to break is more reliably not applied. For this reason, no crack is generated in the interface direction between the wiring conductor layer and the through conductor, and peeling between the wiring conductor layer and the through conductor is eliminated. This eliminates the occurrence of conduction failure between the upper and lower wiring conductor layers,
The multilayer wiring board has even more excellent electrical connection reliability.

As described above, according to the present invention, the peeling between the wiring conductor layer and the penetrating conductor, which is caused by thermal stress, is suppressed in an environmental resistance test such as a heating process or a temperature cycle test when mounting a chip component or the like. It has been possible to provide a multilayer wiring board having excellent electrical connection reliability.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a multilayer wiring board of the present invention.

FIG. 2 is a cross-sectional view showing another example of the embodiment of the multilayer wiring board of the present invention.

FIG. 3 is a sectional view showing still another example of the embodiment of the multilayer wiring board of the present invention.

FIG. 4 is a top view showing the lowermost insulating film layer on the substrate side in an example of the embodiment of the multilayer wiring substrate of the present invention.

[Explanation of symbols]

1 ... substrate 2 ... Multi-layer wiring part 3 ... Wiring conductor layer 4 ... Insulating film layer 5 ... Insulating adhesive layer 6 ... through holes 7 ... Through conductor 8 ... Large diameter through hole

Claims (4)

[Claims] 1. A plurality of insulating film layers made of an organic resin and a wiring conductor layer are laminated and adhered on the substrate in multiple layers between the insulating film layers via an insulating adhesive layer, and the wiring conductors positioned above and below are laminated. A multilayer wiring board in which a through conductor is arranged in a through hole provided in the insulating film layer and the insulating adhesive layer between the layers to electrically connect the layers to each other, wherein At least a part of the outer peripheral portion arranged on the wiring conductor layer arranged on the surface of the substrate is a large-diameter through conductor having a larger cross-sectional area than other through conductors. Multilayer wiring board. 2. The large-diameter through conductor is continuously arranged vertically from the lowermost layer of the insulating film layer and the insulating adhesive layer on the substrate side to the upper insulating film layer and the insulating adhesive layer. The multilayer wiring board according to claim 1, wherein the multilayer wiring board is provided. 3. The multilayer wiring board according to claim 2, wherein a portion of the large-diameter through conductor arranged in the upper layer has a smaller cross-sectional area than a portion of the large-diameter through conductor arranged in the lowermost layer. 4. The multilayer wiring board according to claim 1, wherein the bottom surface of the large-diameter through conductor is embedded in the board together with the wiring conductor layer.