JPH1126939A - Multilayered wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable multilayered wiring board in which prescribed organic resin insulating layer and thin film wiring conductive layer can be exactly formed, by forming a wiring conductor in a board with high density, approximating the thermal expansion coefficient of the board and that of an organic resin insulating layer, widening a joint area between the wiring conductor provided in the board and the organic resin insulating layer for strongly joining them, and strengthening the mechanical strength of the board and flattening the board. SOLUTION: This board is constituted of a board 1 and a multilayered wiring part 4 adhered to at least one main face of the board 1, in which plural organic resin insulating layers 2 and thin film wiring conductive layers 3 are alternately accumulated, and the thin film wiring conductive layers 3 positioned at upper and lower parts are electrically connected through a through-hole conductor 9 provided at the organic resin insulating layers 2. In this case, the board 1 is formed by containing inorganic power in the organic resin, and a wiring conductor 6 formed of a copper foil in relation of 0.1 μm<Ra<=10 μm with surface roughness in its center line mean roughness Ra electrically connected with the thin film wiring conductive layer 3 is adhered to the main face to which at least the multilayered wiring part 4 is adhered.

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, a semiconductor element housing package for housing a semiconductor element, and the like.

[0002]

2. Description of the Related Art Hitherto, a multilayer wiring board used in a hybrid integrated circuit device, a package for accommodating a semiconductor element, or the like, has its wiring conductor formed by a thick film forming technique such as the Mo-Mn method.

[0003] This Mo-Mn method is generally used for tungsten,
Organic solvents for high melting point metal powders such as molybdenum and manganese,
A solvent is added and mixed, and a paste-like metal paste is printed and applied on the outer surface of the raw ceramic body in a predetermined pattern by a screen printing method. Then, a plurality of these are laminated and fired in a reducing atmosphere to obtain a high melting point. This is a method in which the metal powder and the raw ceramic body are sintered and integrated.

The ceramic body on which the wiring conductor is formed is usually an oxide ceramic such as an aluminum oxide sintered body or a mullite sintered body, or an aluminum nitride having an oxide film deposited on the surface. Non-oxide ceramics such as a porous sintered body and a silicon carbide sintered body are used.

However, when the wiring conductor is formed by using the Mo-Mn method, the wiring conductor is formed by screen-printing a metal paste. Had the drawback that it could not be done.

In order to solve the above-mentioned drawbacks, a multilayer wiring board formed at a high density by using a thin film forming technique capable of miniaturization instead of forming a part of the wiring conductor by the conventional thick film forming technique has been proposed. It has come to be used.

A multilayer wiring board in which a part of such a wiring conductor is formed by a thin film forming technique is made of an insulating material such as an aluminum oxide sintered body having a wiring conductor formed by a thick film forming technique such as a screen printing method. An insulating layer made of an organic resin such as an epoxy resin formed by a spin coating method and a thermosetting treatment on the upper surface of a conductive substrate, and a thin film forming technique such as an electroless plating method or a vapor deposition method using a metal such as copper or aluminum. The thin film wiring conductor layers formed by adopting photolithography technology are alternately laminated, and the thin film wiring conductor layers located above and below are attached to the inner wall of the through hole provided in the organic resin insulating layer. It has a structure in which it is electrically connected via a hole conductor, and the wiring conductor formed on the substrate and the thin-film wiring conductor layer are electrically connected. In addition, a bonding pad electrically connected to the thin film wiring conductor layer is formed on the upper surface of the uppermost organic resin insulating layer, and an active component such as a semiconductor element, a capacitive element, a resistor and the like are formed on the bonding pad. The electrodes of the passive components are connected via a brazing material such as solder.

In the above-mentioned multilayer wiring board, a thin-film wiring conductor layer provided between the laminated organic resin insulating layers is provided on the inner wall of the through hole provided in the organic resin insulating layer. The through holes in each organic resin insulating layer are formed by first applying a resist material on each organic resin insulating layer and exposing and developing the resist material to a predetermined position. A window having a shape is formed, and then an etchant is disposed on the window of the resist material, the organic resin insulating layer located on the window of the resist material is removed, and holes (through holes) are formed in the organic resin insulating layer. And finally removing and removing the resist material from the organic resin insulating layer.

[0009]

However, in this multilayer wiring board, the substrate is formed of a ceramic such as an aluminum oxide sintered body, and the ceramic such as the aluminum oxide sintered body has a coefficient of thermal expansion. About 5-1
0 × 10 ⁻⁶ / ° C., which is different from the coefficient of thermal expansion (about 20 to 30 × 10 ⁻⁶ / ° C.) of the organic resin insulating layer deposited on the upper surface. When connecting electronic components such as capacitors and capacitive elements to the bonding pad, or heat generated when the electronic components are activated, due to the difference in the coefficient of thermal expansion between the joints between the substrate and the organic resin insulation layer This causes a disadvantage that the organic resin insulating layer is peeled off from the substrate by the thermal stress.
In particular, when the substrate is large and the bonding area between the substrate and the organic resin insulating layer is large, the above-described disadvantage becomes extremely significant.

In the multilayer wiring board, the aluminum oxide sintered body or the like forming the board has a hard and brittle property. Therefore, when an impact force is applied from the outside, the aluminum oxide sintered body is easily broken by the impact force. Also had the disadvantage of generating

Further, in the multilayer wiring board, since a part of the wiring conductor is replaced by a thin film wiring conductor layer formed by a thin film forming technique, the formation density of the wiring conductor is increased to some extent, but the wiring conductor is formed on the substrate. Since the wiring conductor is still formed by employing a thick film forming technique such as a screen printing method, it has a drawback that it is not possible to cope with a higher density of the wiring conductor.

Further, the substrate made of the aluminum oxide sintered body or the like is liable to cause warpage or dimensional variation due to non-uniform firing shrinkage when the substrate is baked and manufactured. In this case, the organic resin insulating layer and the thin film wiring conductor layer cannot be accurately formed on the substrate surface.

Therefore, the substrate is made to have a high mechanical strength, a coefficient of thermal expansion close to the coefficient of thermal expansion of the organic resin insulating layer, and no occurrence of warpage or dimensional variation due to firing shrinkage. It is conceivable to form the insulating layer with a resin and a wiring conductor formed by etching a copper foil into a predetermined pattern.

However, in the case of this substrate, the wiring conductor provided on the substrate is formed of copper foil, and the copper has a poor bonding property with the organic resin insulating layer, and the surface roughness is the center line average roughness. Since Ra is less than 0.05 μm in (Ra), an organic resin insulating layer and a thin film wiring conductor layer are laminated on a substrate to form a multilayer wiring substrate, and when an external force is applied, the external force is applied. Separation easily occurs between the wiring conductor formed on the upper surface of the substrate and the organic resin insulating layer, and when the separation occurs, the electrical connection between the wiring conductor of the substrate and the thin film wiring conductor layer provided on the organic resin insulating layer is generated. The connection is broken, and a disadvantage that the function is lost as a multilayer wiring board is induced.

The present invention has been made in view of the above-mentioned drawbacks, and has as its object to form a wiring conductor on a substrate at high density, to approximate the thermal expansion coefficient between the substrate and the organic resin insulating layer, The bonding area between the provided wiring conductor and the organic resin insulating layer is increased so that the two are firmly bonded together, and furthermore, the mechanical strength of the substrate is strengthened and the substrate is flattened to provide a predetermined organic resin insulating layer and a thin film wiring conductor layer. It is an object of the present invention to provide a highly-reliable multilayer wiring board that can accurately form a wiring board.

[0016]

According to the present invention, a substrate and a plurality of organic resin insulating layers and thin-film wiring conductor layers, which are attached to at least one principal surface of the substrate and are alternately laminated, are positioned above and below. A multi-layer wiring board comprising a thin-film wiring conductor layer and a multi-layer wiring portion electrically connected via a through-hole conductor provided in an organic resin insulating layer, wherein the substrate is formed by containing an inorganic powder in an organic resin. And at least a main surface on which the multilayer wiring portion is adhered is electrically connected to the thin-film wiring conductor layer, and has a surface roughness having a center line average roughness (R
a) a wiring conductor formed of a copper foil satisfying 0.1 μm ≦ Ra ≦ 10 μm is applied.

Further, in the present invention, the particle diameter of the inorganic powder is 0.1.
It is characterized in that the thickness is from 05 μm to 10 μm.

Further, the present invention relates to a method for producing a composition comprising the inorganic powder having a content of 6%.
It is characterized in that the content is 0% to 95% by weight.

According to the multilayer wiring board of the present invention, the substrate on which the multilayer wiring portion composed of the organic resin insulating layer and the thin-film wiring conductor layer is to be adhered is made of an organic resin containing, for example, 60 to 95% by weight of an inorganic powder. %, The coefficient of thermal expansion of the substrate is close to the coefficient of thermal expansion of the organic resin insulating layer. As a result, even when heat is applied to the substrate and the organic resin insulating layer, the thermal expansion of the two layers is between them. There is no occurrence of stress due to the difference in the coefficients, and the two can be joined very firmly.

Further, according to the multilayer wiring board of the present invention, since the board is formed by incorporating an inorganic powder in an organic resin having excellent toughness, the mechanical strength of the board is increased, and an impact force is applied from the outside. It will not be easily damaged.

Further, according to the multilayer wiring board of the present invention,
The substrate is formed by incorporating inorganic powder into the organic resin.The organic resin solidifies by thermosetting or photocuring, and because it does not involve a firing step, warpage and dimensional variations occur due to uneven firing shrinkage accompanying firing. As a result, as a result, the substrate has a predetermined size with its surface flat, and the organic resin insulating layer and the thin-film wiring conductor layer can be accurately formed on the substrate surface.

Further, according to the multilayer wiring board of the present invention, the wiring conductor provided on the substrate is made of a copper foil processed into a predetermined pattern by etching or the like, and the thin film wiring conductor layer of the multilayer wiring portion is formed of a thin film. All wiring can be miniaturized because it is formed by adopting the forming technology,
As a result, it is possible to form the wiring with extremely high density.

Further, according to the multilayer wiring board of the present invention, the surface roughness of the wiring conductor made of copper foil provided on the upper surface of the substrate is defined as a center line average roughness (Ra) in a range of 0.1 μm ≦ Ra ≦ 10 μm. When a multilayer wiring portion is formed on a substrate because of moderate roughness, the bonding area between the wiring conductor on the upper surface of the substrate and the organic resin insulating layer of the multilayer wiring portion becomes large, and the bonding strength becomes strong. No delamination occurs even when applied.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of a multilayer wiring board according to the present invention, wherein 1 is a substrate, 2 is an organic resin insulating layer, and 3 is a thin-film wiring conductor layer.

On the upper surface of the substrate 1, there is provided a multilayer wiring portion 4 in which a large number of organic resin insulating layers 2 and thin film wiring conductor layers 3 are alternately laminated in multiple layers, and the multilayer wiring portion 4 is supported. Act as a supporting member.

The substrate 1 is formed by laminating an insulating layer 5 formed by incorporating an inorganic powder in an organic resin and a wiring conductor 6 formed by processing a copper foil into a predetermined pattern by etching. It has a structure in which upper and lower wiring conductors 6 are connected via via-hole conductors 7 provided in the insulating layer 5.

The insulating layer 5 of the substrate 1 is made of an organic resin such as polyphenylene ether resin, bismaleimide triazine resin, epoxy resin, polyimide resin, fluororesin, phenol resin, silicon oxide, aluminum nitride, silicon carbide, barium titanate. , Strontium titanate, zeolite, calcium titanate, and the like, and the inorganic powder contains the inorganic powder so that the thermal expansion coefficient of the substrate 1 can be reduced by the thermal expansion coefficient of the multilayer wiring portion 4 described later (about 20 to 3).
0 × 10 ⁻⁶ / ° C.), which is about 20 × 10 ⁻⁶ / ° C., so that even if heat is applied to both the substrate 1 and the multilayer wiring portion 4, the difference in the thermal expansion coefficient between the two. No thermal stress is generated due to the
Can be firmly joined.

In addition, since the insulating layer 5 of the substrate 1 is formed by including an inorganic powder in an organic resin having excellent toughness such as polyphenylene ether resin or bismaleimide triazine resin, the mechanical strength of the substrate 1 is increased. As a result, even when an impact force is applied to the substrate 1 from the outside, the substrate 1 is not easily damaged.

When the amount of the inorganic powder is less than 60% by weight, the thermal expansion coefficient of the insulating layer 5 can be reduced in the insulating layer 5 formed by incorporating the inorganic powder into the organic resin.
When heat is applied to both the substrate 1 and the multilayer wiring portion 4 formed by laminating the insulating layers 5 in multiple layers, the difference is caused by the difference between the two. There is a risk that a large thermal stress is generated, and the thermal stress causes peeling between the substrate 1 and the multilayer wiring portion 4. When the content exceeds 95% by weight, the inorganic powder to be added is contained in an organic resin. It cannot be firmly bonded, and it tends to be difficult to obtain an insulating layer 5 having a predetermined shape. Therefore, it is preferable that the amount of the inorganic powder in the insulating layer 5 formed by including the inorganic powder in the organic resin is in the range of 60% by weight to 95% by weight.

The insulating layer 5 formed by incorporating the inorganic powder in the organic resin has a particle diameter of the inorganic powder of 0.0%.
When the thickness is less than 5 μm, the inorganic powder is agglomerated and does not uniformly disperse in the organic resin. As a result, the mechanical strength of the insulating layer 5 is reduced, and the substrate 1 is formed by laminating the insulating layer 5 vertically. Also reduced the mechanical strength of
If it exceeds, large irregularities are formed on the surface of the insulating layer 5 and large irregularities are also formed on the surface of the substrate 1 formed by laminating the insulating layers 5 in layers vertically, so that the desired surface There is a tendency that it is difficult to accurately form the multi-layer wiring portion 4. Therefore, it is preferable that the insulating layer 5 formed by including the inorganic powder in the organic resin has a particle diameter of the inorganic powder in the range of 0.05 μm to 10 μm.

Further, the wiring conductor 6 of the substrate 1 is made of a copper foil processed into a predetermined pattern, and the wiring conductor 6 is electrically connected to a thin film wiring conductor layer 3 of a multilayer wiring portion 4 described later. It functions to electrically connect the layer 3 to an external electric circuit or to electrically connect a plurality of thin film wiring conductor layers 3 to each other.

The wiring conductor 6 is formed by attaching a copper foil having a predetermined pattern to the upper surface of the insulating layer 5 by etching or the like so that the upper and lower layers of the insulating layer 5 and the insulating layer 5 are separated from each other. The wiring conductors 6 are formed on the surface of the substrate 1 which is formed by alternately stacking the wiring conductors in multiple layers.

Since the wiring conductor 6 is formed by etching a copper foil, the line width of the wiring conductor 6 can be made extremely thin, thereby forming the wiring conductor 6 at a high density. Becomes possible.

The wiring conductor 6 is led out to the main surface of the substrate 1 on which the multilayer wiring portion 4 is to be adhered, but the surface has an appropriate center line average roughness (Ra) of 0.1 μm ≦ Ra ≦ 10 μm. It is rough. Therefore, when the multilayer wiring portion 4 is formed on the surface of the substrate 1, the bonding area between the wiring conductor 6 on the upper surface of the substrate 1 and the organic resin insulating layer 2 of the multilayer wiring portion 4 becomes large, and the bonding strength becomes strong. Separation does not occur even by the application.

The surface of the wiring conductor 6 exposed on the surface of the substrate 1 has a center line average roughness (Ra) of Ra.
If <0.1 μm, the bonding strength between the wiring conductor 6 on the upper surface of the substrate 1 and the organic resin insulating layer 2 of the multilayer wiring section 4 becomes weak, and if 10 μm <Ra, a large variation occurs in the thickness of the wiring conductor 6. The variation in the conduction resistance of the wiring conductor 6 becomes extremely large. . Accordingly, the surface of the wiring conductor 6 exposed on the surface of the substrate 1 has a center line average roughness (Ra) of 0.1 μm ≦ Ra ≦ 10 μm.
The range is preferably 2 μm ≦ Ra ≦ 6 μm.

The wiring conductors 6 are vertically arranged in multiple layers with the insulating layer 5 interposed therebetween. Each of the wiring conductors 6 positioned vertically with the insulating layer 5 interposed therebetween is a via hole provided in the insulating layer 5. They are electrically connected via conductors 7.

The via-hole conductor 7 serves to electrically connect the wiring conductors 6 positioned above and below, and is made of a conductive ink or the like containing a conductive resin or metal powder. It is formed by filling holes.

As a specific method of manufacturing the substrate 1 formed by alternately stacking the insulating layers 5 and the wiring conductors 6 in a multilayer, as shown in FIG. 2, first, as shown in FIG. ,
The insulating layer 5 having the via-hole conductor 7 is formed. The insulating layer 5 having the via-hole conductor 7 first forms a through hole 7a in the insulating layer 5. This through hole 7a is formed by, for example, laser processing, micro drilling, or the like.
The through hole 7a is formed by filling the conductive paste 7 containing the metal powder.

Next, as shown in FIG. 2B, a wiring conductor 6 to be formed on the surface of the insulating layer 5 is formed on the surface of the transfer sheet 12. The wiring conductor 6 is formed by bonding a copper foil to the surface of the transfer sheet 12, applying a resist on the surface of the copper foil in a predetermined pattern, and then performing an etching process and a resist removal.

Then, as shown in FIG. 2C, the transfer sheet 12 on which the wiring conductors 6 are formed is positioned on the surface of the insulating layer 5 having the via-hole conductors 7 and laminated and pressure-bonded. The sheet 12 is peeled off, thereby forming the insulating layer 5 having the wiring conductor 6 electrically connected to the via-hole conductor 7.

Finally, as shown in FIG. 2D, the substrate 1 is formed by vertically stacking a plurality of insulating layers 5 each having a wiring conductor 6 electrically connected to the via hole conductor 7. .

Further, the substrate 1 has a multilayer wiring portion 4 formed by alternately laminating a plurality of organic resin insulating layers 2 and thin film wiring conductor layers 3 on the upper surface thereof. The organic resin insulating layer 2 constituting the portion 4 functions to electrically insulate the thin film wiring conductor layers 3 located above and below, and the thin film wiring conductor layer 3 functions as a transmission path for transmitting electric signals.

The organic resin insulating layer 2 of the multilayer wiring section 4
It is made of an organic resin such as an epoxy resin, a bismaleimide triazine resin, a polyphenylene ether resin, and a fluororesin. For example, when it is made of an epoxy resin, it is amine-cured to a bisphenol A epoxy resin, a novolak epoxy resin, a glycidyl ester epoxy resin, or the like. And a curing agent such as an imidazole-based curing agent and an acid anhydride-based curing agent are added and mixed to obtain a paste-like epoxy resin precursor, and the epoxy resin precursor is applied to the upper portion of the substrate 1 by spin coating. After that, this is brought to 80 ° C. to 200 ° C.
It is formed by heat-treating with heat of 0.5 ° C. for 0.5 to 3 hours and heat curing. In this case, the surface of the substrate 1 is flat,
In addition, since the same organic resin as that of the organic resin insulating layer 2 is exposed, the organic resin insulating layer 2 and the substrate 1 are bonded very firmly, whereby the multilayer wiring portion 4 is firmly adhered on the substrate 1. I can put it.

The organic resin insulating layer 2 of the multilayer wiring section 4
Has a through hole 8 having a minimum diameter of about 1.5 times the thickness of the organic resin insulating layer 2 at each predetermined position.
, And acts as a forming hole for forming a through-hole conductor 9 for electrically connecting each of the thin-film wiring conductor layers 3 located above and below via.

The through-holes 8 provided in the organic resin insulating layer 2 are formed by applying a well-known photolithography technique to the organic resin insulating layer 2, specifically, by applying a resist material on each organic resin insulating layer 2. A window having a predetermined shape is formed at a predetermined position by performing exposure and development thereon, and then an etchant is disposed at the window of the resist material, and an organic resin insulating layer positioned at the window of the resist material is formed. 2, a hole (through hole) is formed in the organic resin insulating layer 2, and finally, the resist material is peeled off from the organic resin insulating layer 2 and removed to form a predetermined diameter.

Further, a thin-film wiring conductor layer 3 having a predetermined pattern is formed on the upper surface of each organic resin insulating layer 2, and a through-hole conductor 9 is formed on the inner wall of a through hole 8 provided in each organic resin insulating layer 2. Each of the thin film wiring conductor layers 3 located above and below the organic resin insulating layer 2 with the through-hole conductor 9 interposed therebetween is electrically connected.

The thin-film wiring conductor layer 3 and the through-hole conductor 9 formed on the upper surface of each organic resin insulating layer 2 and the inner wall of the through-hole 8 are made of a metal material such as copper, nickel, gold, and aluminum by electroless plating. It is formed by employing a thin film forming technique such as a vapor deposition method and a sputtering method and a photolithographic technique. For example, in the case of being formed of copper, the upper surface of the organic resin insulating layer 2 and the inner surface of the through hole 8 are formed. 0.06 mol / l copper sulfate, 0.3 mol / l formalin, 0.35 sodium hydroxide
Mol / l, an electroless steel plating bath consisting of 0.35 mol / l of ethylenediaminetetraacetic acid and a thickness of 1 μm.
Each of the organic resin insulating layers 2 is formed by depositing a copper layer having a thickness of 40 μm to 40 μm, and thereafter processing the copper layer into a predetermined pattern by employing photolithography technology.
The gap is formed on the inner wall of the through hole 8. in this case,
Since the thin-film wiring conductor layer 3 and the through-hole conductor 9 are formed by a thin-film forming technique, the wiring can be miniaturized, thereby making it possible to form the thin-film wiring conductor layer 3 at an extremely high density.

The multilayer wiring portion 4 formed by alternately laminating the organic resin insulating layers 2 and the thin film wiring conductor layers 3 in a multilayer structure has a center line average roughness (R
By setting a rough surface of 0.05 μm ≦ Ra ≦ 5 μm in a), the bonding between the organic resin insulating layer 2 and the thin-film wiring conductor layer 3 and the bonding between the organic resin insulating layers 2 located above and below can be made strong. . Therefore, the upper surface of each organic resin insulating layer 2 of the multilayer wiring portion 4 is roughened by an etching method or the like,
Center line average roughness (Ra): 0.05 μm ≦ Ra ≦ 5 μm
It is preferable to make the surface rough.

The count value of the height (Pc) of the unevenness at a length of 2.5 mm on the surface of the organic resin insulating layer 2 is 500 or more for 1 μm ≦ Pc ≦ 10 μm.
2500 μm of 1 μm ≦ Pc ≦ 1 μm, 0.01 μm
If ≦ Pc ≦ 0.1 μm is set to 12,500 or more, the bonding between the organic resin insulating layer 2 and the thin-film wiring conductor layer 3 and the bonding between the organic resin insulating layers 2 located above and below become stronger. Therefore, the organic resin insulating layer 2 has a thickness of 2.5
The count value of the height (Pc) of the unevenness in the length of mm is 1 μm ≦ Pc ≦ 10 μm.
2500 or more m ≦ Pc ≦ 1 μm, 0.01 μm ≦ P
It is preferable that c ≦ 0.1 μm is set to 12,500 or more.

The count value of the center line average roughness (Ra) of the upper surface of the organic resin insulating layer 2 and the height of the unevenness (Pc) at a length of 2.5 mm are obtained by measuring the surface of the organic resin insulating layer 2 with an atomic force. Microscope (Dimensio manufactured by Digital Instruments Inc.
n 3000-Nano Scope III)
m), the surface condition was inspected and measured, and each numerical value was obtained from the measurement result.

The center line average roughness (Ra) is 0.0
5 μm ≦ Ra ≦ 5 μm, the count value of the height of unevenness (Pc) at a length of 2.5 mm is 1 μm ≦ Pc ≦ 10 μm
m is 500 or more, and 0.1 μm ≦ Pc ≦ 1 μm is 250
0 or more, 0.01 μm ≦ Pc ≦ 0.1 μm is 1250
Zero or more organic resin insulating layers 2 are subjected to a reactive ion etching process by blowing a gas such as CHF ₃ , CF ₄ , Ar, etc. onto the upper surface of the organic resin insulating layers 2, whereby the surface is roughened to a predetermined roughness. Is done.

Further, when the thickness of each of the organic resin insulating layers 2 exceeds 100 μm, the etching processing time becomes longer when the through holes 8 are formed by employing photolithography technology in the organic resin insulating layers 2. It is difficult to form the through hole 8 into a desired clear shape, and if the thickness is less than 5 μm, rough surface processing for increasing the bonding strength of the organic resin insulating layer 2 located above and below the organic resin insulating layer 2 is performed. At the time of application, there is a risk that an unnecessary hole is formed in the organic resin insulating layer 2 and an unnecessary electric short circuit is caused in the thin film wiring conductor layer 3 located above and below. Accordingly, the organic resin insulating layer 2 has a thickness of 5 μm to 100 μm.
It is preferable to set the range of m.

Further, when the thickness of each thin-film wiring conductor layer 3 of the multilayer wiring portion 4 is less than 1 μm, the electric resistance of each thin-film wiring conductor layer 3 becomes large, and a predetermined value is applied to each thin-film wiring conductor layer 3. It is difficult to transmit the electric signal of
When the thickness exceeds 40 μm, a large stress is generated inside the thin-film wiring conductor layer 3 when the thin-film wiring conductor layer 3 is adhered to the organic resin insulating layer 2, and the large intrinsic stress causes the thin-film wiring conductor layer 3 to form an organic resin. It becomes easy to peel off from the insulating layer 2. Therefore, it is preferable that the thickness of each thin-film wiring conductor layer 3 of the multilayer wiring portion 4 be in the range of 1 μm to 40 μm.

The organic resin insulating layer 2 and the thin-film wiring conductor layer 3
And a multi-layer wiring portion 4 formed by alternately laminating the bonding pads 10 on the uppermost organic resin insulating layer 2, and further, a bonding pad 10 electrically connected to the thin film wiring conductor layer 3 is formed. The bonding pad 10 is used to connect the electrodes of the electronic component A such as a semiconductor element, a capacitance element and a resistor to the thin film wiring conductor layer 3.
To electrically connect to the

The bonding pad 10 has, for example, a circular shape with a diameter of 200 to 500 μm. If the electrode of an electronic component A such as a semiconductor element or a capacitor is connected to the bonding pad 10 via a brazing material, The electrodes of the electronic component A such as a semiconductor element and a capacitance element are electrically connected to the thin-film wiring conductor layer 3.

The bonding pad 10 is made of the same metal material as the thin film wiring conductor layer 3, specifically, copper, nickel, gold,
It is made of a metal material such as aluminum, and is formed at the same time as the thin-film wiring conductor layer 3 is formed on the uppermost organic resin insulating layer 2 so as to be electrically connected to the thin-film wiring conductor layer 3.

Thus, according to the above-described multilayer wiring board, the bonding pad 1 provided on the uppermost organic resin insulating layer 2
0, the electrodes of the electronic component A such as a semiconductor element and a capacitance element are connected via a brazing material made of solder or the like, and the electrodes of the electronic component A are electrically connected to the thin film wiring conductor layer 3 via the bonding pads 10. As a result, a semiconductor device or a hybrid integrated circuit device is obtained. If a part of the thin film wiring conductor layer 3 is connected to an external electric circuit, the electronic component A is connected to the external electric circuit.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. A multilayer wiring portion 4 formed by alternately laminating a plurality of organic resin insulating layers 2 and a plurality of thin film wiring conductor layers 3 is applied only on the side of the substrate 1. It may be provided only on the upper and lower surfaces.

In the above embodiment, the organic resin of the substrate 1 is made of a thermosetting epoxy resin or the like, but it may be made of a photocurable resin. In this case, since the organic resin of the substrate 1 is solidified by light irradiation and does not involve a firing step, there is no warpage or dimensional variation due to uneven firing shrinkage due to firing, and as a result, the substrate 1 has its surface Has a flat predetermined dimension, and it is possible to accurately form the multilayer wiring portion 4 including the organic resin insulating layer 2 and the thin film wiring conductor layer 3 on the surface of the substrate 1.

[0060]

According to the multilayer wiring board of the present invention, the substrate on which the multilayer wiring portion composed of the organic resin insulating layer and the thin-film wiring conductor layer is to be adhered is made of, for example, 60% by weight or less of inorganic powder in the organic resin. The thermal expansion coefficient of the substrate is close to the thermal expansion coefficient of the organic resin insulating layer because the substrate is formed so as to contain 95% by weight. There is no generation of stress due to the difference in the coefficient of thermal expansion, and the two can be joined very firmly.

Further, according to the multilayer wiring board of the present invention, since the board is formed by incorporating an inorganic powder in an organic resin having excellent toughness, the mechanical strength of the board is increased, and an impact force is applied from the outside. It will not be easily damaged.

Further, according to the multilayer wiring board of the present invention,
The substrate is formed by incorporating inorganic powder into the organic resin.The organic resin solidifies by thermosetting or photocuring, and because it does not involve a firing step, warpage and dimensional variations occur due to uneven firing shrinkage accompanying firing. As a result, as a result, the substrate has a predetermined size with its surface flat, and the organic resin insulating layer and the thin-film wiring conductor layer can be accurately formed on the substrate surface.

Further, according to the multilayer wiring board of the present invention, the wiring conductor provided on the substrate is made of a copper foil processed into a predetermined pattern by etching or the like, and the thin film wiring conductor layer of the multilayer wiring portion is formed of a thin film. All wiring can be miniaturized because it is formed by adopting the forming technology,
As a result, it is possible to form the wiring with extremely high density.

Further, according to the multilayer wiring board of the present invention, the surface roughness of the wiring conductor made of copper foil disposed on the upper surface of the substrate is set to a center line average roughness (Ra) in a range of 0.1 μm ≦ Ra ≦ 10 μm. When a multilayer wiring portion is formed on a substrate because of moderate roughness, the bonding area between the wiring conductor on the upper surface of the substrate and the organic resin insulating layer of the multilayer wiring portion becomes large, and the bonding strength becomes strong. No delamination occurs even when applied.

[Brief description of the drawings]

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

2 (a) to 2 (d) are cross-sectional views for explaining respective steps of a method for manufacturing the multilayer wiring board shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Organic resin insulating layer 3 ... Thin film wiring conductor layer 4 ... Multilayer wiring part 5 ... Insulating layer 6 ... Wiring conductor 7 ... Via-hole conductor 9 ... Through-hole conductor A: Electronic components

Claims (3)

[Claims] 1. A substrate and a plurality of organic resin insulating layers and a thin film wiring conductor layer which are attached to at least one main surface of the substrate and are alternately laminated, and the upper and lower thin film wiring conductor layers are organic resin insulation layers. A multilayer wiring board comprising a multilayer wiring portion electrically connected via a through-hole conductor provided in a layer, wherein the substrate is formed by incorporating an inorganic powder in an organic resin, and at least the multilayer The thin film wiring conductor layer is electrically connected to the main surface on which the wiring portion is attached, and has a surface roughness of 0.1 μm ≦ Ra ≦ in terms of center line average roughness (Ra).
A multilayer wiring board, on which a wiring conductor formed of a copper foil having a thickness of 10 μm is adhered. 2. The multilayer wiring board according to claim 1, wherein said inorganic powder has a particle size of 0.05 μm to 10 μm. 3. The multilayer wiring board according to claim 1, wherein the content of said inorganic powder is 60% by weight to 95% by weight.