JP2001298126A - Wiring substrate and electronic component using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems of low impact resistance and cracks since an insulation base constituting an electronic component consists of ceramics, and of low dielectric constant and that an electronic component cannot be miniaturized. SOLUTION: A wiring substrate 4 is formed by laminating a plurality of insulation layers 1a, 1b, 1c, 1d, 1e up and down which consist of inorganic insulation powder of 10 to 70 wt.% and organic material of 30 to 90 wt.% and are formed by binding inorganic insulation powder by organic material, and applying a wiring conductor 2 among the insulation layers 1a, 1b, 1c, 1d, 1e and/or to exposed insulation layers 1a, 1b, 1c, 1d, 1e surfaces. At least one layer of the insulating layers 1a, 1b, 1c, 1d, 1e has permittivity in upper and lower surface direction of 30 or more and at least a pair of counter electrode 3 are disposed between the upper and lower surfaces. Since the insulation base 1 is formed by binding inorganic insulation powder by organic material which is excellent in tenacity, cracks or the like are not generated in the insulation base 1 even if the wiring substrate 4 collide hard against each other.

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 electronic components used for electronic devices such as various AV devices, home appliances, communication devices, computers, and peripheral devices thereof.

[0002]

2. Description of the Related Art Generally, current electronic components are required to be small, light, thin, high-performance, high-performance, high-quality, and high-reliable, as represented by mobile communication devices. Wiring boards used for electronic components have also been required to be reduced in size.

Such a wiring board, for example, a wiring board used for a package for housing a semiconductor element for housing a semiconductor element has a plurality of insulating layers made of ceramics such as a sintered body of aluminum oxide. An insulating substrate having a concave portion for accommodating a semiconductor element in the center of the upper surface, and a wiring conductor made of a high melting point metal such as tungsten and molybdenum led out from the periphery of the concave portion to the lower surface of the insulating substrate. The semiconductor element is bonded and fixed to the bottom surface of the concave portion with an adhesive such as glass, resin, brazing material, etc., and each electrode (power supply electrode, ground electrode, signal electrode) of the semiconductor element is connected via an electrical connection means such as a bonding wire. To electrically connect to the wiring conductor, and then, on the upper surface of the insulating base, place a lid made of metal, ceramics, etc. on the upper surface of the insulating base. A block way, glass, resin,
A semiconductor device as a product is formed by joining a semiconductor element in a concave portion of the insulating base in an airtight manner by joining through a sealing material such as a brazing material, and a portion of the wiring conductor led out to the lower surface of the insulating base is an external electric circuit. Each electrode of the semiconductor element is electrically connected to the external electric circuit board by connecting to the wiring conductor of the board.

Further, in this conventional wiring board, an insulating layer constituting an insulating base inside the insulating base is provided in order to prevent a malfunction of the semiconductor element due to a fluctuation of a power supply voltage and a ground power supply connected to the semiconductor element. By disposing a pair of wide-area opposed electrodes made of a high melting point metal powder such as tungsten and molybdenum opposed to each other with one of them sandwiched, a capacitance element is formed between the pair of opposed electrodes, One is electrically connected to the power supply electrode of the semiconductor element and the other is electrically connected to the ground electrode of the semiconductor element, so that the fluctuation of the power supply voltage connected to the semiconductor element is suppressed.

Further, in this wiring board, a high melting point metal powder such as tungsten and molybdenum is dispersed in an insulating layer sandwiched between a pair of opposing electrodes, thereby increasing the dielectric constant of the insulating layer to form a pair of opposing electrodes. A device for providing a large capacitance to a capacitor formed between electrodes has also been devised.

A conventional wiring board is manufactured by a ceramic green sheet laminating method. Specifically, an organic binder suitable for a ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide is used.
A plurality of ceramic green sheets are obtained by adding and mixing a solvent or the like to form a slurry and forming the sheet into a sheet shape by employing a conventionally known doctor blade method. Thereafter, an appropriate punching process is performed on the ceramic green sheet. Apply and paste the metal paste that will be the wiring conductor and the counter electrode in a predetermined pattern, and finally laminate the ceramic green sheets in a predetermined order to form a green ceramic molded body and place the green ceramic molded body in a reducing atmosphere at about 1600 ° C.
It is manufactured by firing at a high temperature.

[0007]

However, in this conventional wiring board, since the ceramics such as the aluminum oxide sintered body constituting the insulating base have a hard and brittle property, the automatic wiring of the transfer process and the semiconductor device manufacturing is difficult. When the wiring boards collide with each other or the wiring board and a part of the semiconductor device manufacturing automatic line violently collide with each other, chips, cracks, cracks, etc. occur in the insulating base, and as a result, the semiconductor element can be housed in an airtight manner. In addition, the semiconductor device cannot operate normally and stably for a long period of time.

Further, in this conventional wiring board, since the relative dielectric constant of an aluminum oxide sintered body or the like constituting the insulating base is as low as about 10 at most, the insulating layer constituting the insulating base is sandwiched inside the insulating base. It is difficult to provide a large capacitance to a capacitor formed by facing a pair of counter electrodes, and as a result, the area of the counter electrode needs to be large in order to obtain a large capacitance. There is a problem that it is difficult to reduce the size of the wiring board.

[0009] Even when a high melting point metal powder such as tungsten and molybdenum is dispersed in an insulating layer sandwiched between a pair of opposing electrodes to increase the dielectric constant of the insulating layer,
By increasing the amount of the refractory metal powder to be dispersed, the relative dielectric constant of the insulating layer can be gradually increased, but the refractory metal powders in the insulating layer come into contact with each other and the electric power is applied between the opposing electrodes. There is a problem that a short circuit occurs or the withstand voltage of the capacitance element is reduced, so that the semiconductor element cannot be operated normally and stably.

The insulating layer sandwiched between the pair of counter electrodes is formed of a high dielectric material such as barium titanate porcelain, and a capacitor formed between the counter electrodes while maintaining electrical insulation between the counter electrodes. It is conceivable to increase the capacitance of the element. In this case, however, a high-dielectric material such as barium titanate has a firing temperature, a firing atmosphere, or a firing shrinkage rate of an aluminum oxide sintered body or tungsten.・ Firing temperature and firing atmosphere of high melting point metal powder such as molybdenum,
Alternatively, since it is significantly different from the firing shrinkage, it is difficult to fire simultaneously with a high melting point metal powder such as an aluminum oxide-based sintered body or tungsten / molybdenum, so that a predetermined wiring board cannot be obtained. I was

In order to solve such a problem, there has been proposed a composite material having a high dielectric constant obtained by binding an inorganic dielectric powder with an organic resin (Japanese Patent Laid-Open No. 11-68322). However, the relative permittivity of this composite material is as low as about 20, and the relative permittivity of the dielectric powder contained therein cannot be sufficiently exhibited. As a result, in order to obtain a large capacitance, There is a problem that the area of the counter electrode needs to be increased, and a small-sized wiring board cannot be obtained.

The present invention has been devised in view of the problems of the prior art, and has as its object to provide a small-sized electronic component excellent in impact resistance using a wiring board having a high dielectric constant. It is in.

[0013]

According to the present invention, there is provided a wiring board comprising:
Up to 70% by weight of an inorganic insulating powder and 30 to 90% by weight of an organic material, wherein a plurality of insulating layers are formed by combining the inorganic insulating powder with an organic material, and a plurality of insulating layers are laminated one above another, and the insulating layers are exposed and / or exposed. What is claimed is: 1. A wiring board comprising a wiring conductor provided on a surface of an insulating layer, wherein the insulating layer has a relative dielectric constant of at least one of upper and lower surfaces of 30 or more, and at least one pair of opposing electrodes disposed between upper and lower surfaces. It is characterized by being provided.

Further, the wiring board of the present invention is characterized in that an insulating layer having a relative dielectric constant of 30 or more in the vertical direction has a dielectric powder of 10 to 70% by weight and an organic material having an anisotropic dielectric of 30 to 90% by weight. Wherein the relative permittivity in the direction in which the relative permittivity is maximum is 1/100 to 1/2 of the relative permittivity of the dielectric powder.

Further, an electronic component according to the present invention is characterized by comprising the above-mentioned wiring board and an electronic element mounted on the wiring board and electrically connected to a wiring conductor.

According to the wiring substrate of the present invention, since the insulating base is formed by bonding inorganic insulating powder or dielectric powder with an organic material having excellent toughness, the wiring substrates or the wiring substrate and the semiconductor device are manufactured. Even if a part of the automatic line collides violently, the insulating substrate does not chip, crack, crack, etc. With this arrangement, a capacitor having a large capacitance can be obtained between the pair of opposed electrodes.

Further, according to the electronic component of the present invention, it is not necessary to increase the area of the counter electrode more than necessary in order to obtain a large capacitance, and a small electronic component can be obtained.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a wiring board and an electronic component according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an example of an electronic component when a semiconductor element is mounted as an electronic element on the wiring board of the present invention. In this figure, 1 is an insulating base, 2 is a wiring conductor, 3 is a counter electrode, and the wiring board 4 is mainly composed of these. Reference numeral 5 denotes a semiconductor element, and the electronic component 6 of the present invention mainly includes the wiring board 4 and the semiconductor element 5.

In this embodiment, the insulating substrate 1 has five insulating layers 1a,
1b, 1c, 1d and 1e are laminated, and a stepped recess A for accommodating the semiconductor element 5 is provided in the center of the upper surface thereof. It is adhesively fixed via an agent.

The insulating layers 1a, 1a constituting the insulating base 1 are
At least one of the layers b, 1c, 1d, and 1e (the insulating layer 1d in the example of this figure) is formed of an insulating layer having a relative dielectric constant of 30 or more in the upper and lower surface directions. When a pair of opposing electrodes 3 are provided on the lower surface and a capacitance element is formed between the opposing electrodes 3, the capacitance of the capacitance element is extremely high because the relative permittivity in the upper and lower direction of the insulating layer 1d is as high as 30 or more. It can be big.

Since the dielectric powder contained in the insulating layer 1d does not conduct electricity, there is no possibility that an electric short circuit or a decrease in withstand voltage occurs between the opposing electrodes 3 opposed to each other with the insulating layer 1d interposed therebetween. Not at all.

The insulating layers 1a, 1b, 1c,
1e is an inorganic insulating powder of aluminum oxide, silicon nitride, aluminum nitride, silicon carbide, titanium oxide, barium oxide, strontium oxide, zirconium oxide, calcium oxide, zeolite, etc., epoxy resin, phenol resin, polyimide resin, bismaleimide resin It is formed by bonding with a thermosetting resin such as a thermosetting polyphenylene ether resin or a thermoplastic resin such as a liquid crystal polyester / polyphenylene ether-based resin, and each of them, together with an insulating layer 1d described below, is made of inorganic toughness powder. Is formed by bonding with an organic material such as a thermosetting resin or a thermoplastic resin, which is excellent in heat resistance, so that even if an external force is applied to the insulating base 1, the insulating base 1 may be chipped, cracked, or cracked by the external force. Never.

The insulating substrate 1 has, for example, a particle size of 0.1 to 15 μm.
Inorganic insulating powder such as aluminum oxide, silicon nitride, aluminum nitride, silicon carbide, titanium oxide, barium oxide, strontium oxide, zirconium oxide, calcium oxide, epoxy resin, phenol resin, polyimide resin, bismaleimide resin, and thermosetting Thermosetting resin such as reactive polyphenylene ether resin or liquid crystal polyester
A paste obtained by adding a thermoplastic resin such as a polyphenylene ether-based resin and a solvent, a plasticizer, a dispersant, and the like is formed into a sheet by employing a conventionally known sheet forming method such as a doctor blade method. Insulating layers 1a, 1 in
b, 1c, and a plurality of precursor sheets to be used as the insulating layers 1a, 1b, 1c, and 1e, and a precursor sheet to be the insulating layer 1d as described below. The punching process is performed by using a conventionally known punching method, and the insulating layers 1a, 1b, 1c,
1d and 1e are laminated and crimped in a predetermined order, and finally, the laminated and crimped insulating layers 1a, 1b, 1c, 1d and 1e are heated at a temperature of about 100 to 300 ° C.
It is manufactured by hot-pressing at a pressure of 0.4 to 10 MPa for 30 minutes to 24 hours and thermally curing the same.

An insulating layer 1d having a relative dielectric constant of 30 or more in the vertical direction.
Is composed of 10 to 70% by weight of a dielectric powder and 30 to 90% by weight of an organic material having anisotropic dielectric property. When the dielectric powder is less than 10% by weight, the relative dielectric constant is smaller than 30. When the content exceeds 70% by weight, the amount of the organic resin decreases, and the strength of the composite member tends to decrease.
Therefore, it is preferable that the compounding ratio between the dielectric powder and the organic material be 10 to 70% by weight of the dielectric powder and 30 to 90% by weight of the organic material.

The insulating layers 1a, 1a constituting the insulating base 1
As for b, 1c, and 1e, it is preferable that the content of the inorganic insulating powder contained is made substantially the same as the content of the dielectric powder contained in the insulating layer 1d. If the content of the inorganic insulating powder and the content of the dielectric powder are significantly different, the insulating layer 1d and the other insulating layers 1a, 1
When the thermal expansion coefficients of b, 1c, and 1e are significantly different, the semiconductor element 4 generates heat during operation, and when this heat is applied to both the insulating layer 1d and the other insulating layers 1a, 1b, 1c, and 1e, A large stress is generated between the two due to the difference in the coefficient of thermal expansion between them, and this stress causes separation between the two or cracks or chips occur in the insulating layer 1d or the insulating layers 1a, 1b, 1c, 1e. There is a tendency. Therefore, it is preferable that the amount of the inorganic insulating powder contained in the insulating layers 1a, 1b, 1c, and 1e substantially coincides with the content of the dielectric material contained in the insulating layer 1d.

The insulating layer 1d is made of an inorganic dielectric powder such as titanium oxide, barium oxide, strontium oxide, zirconium oxide, calcium oxide or the like having a relative dielectric constant of about 100 to 5,000, or a compound or mixture thereof, or a potassium titanate whisker.
Fibrous high dielectric powder such as aluminum borate whisker, acicular titanium oxide, silica alumina fiber, alumina fiber, etc.
High dielectric powders such as barium titanate, calcium titanate, barium stannate, barium zirconate, and strontium zirconate have anisotropic dielectric properties, have orientational sites in the molecule, and have the principal axis direction of the molecule. Relative permittivity ε
The ratio ε _P / ε _{V of P} and the relative permittivity ε _{V in} the direction orthogonal to the main axis direction
Are formed by bonding with an organic material of 1.2 to 10.

When the dielectric powder used for the insulating layer 1d has a relative dielectric constant of less than 100, the relative dielectric constant of the insulating layer 1d tends to be smaller than 30. 50
If it exceeds 00, the dielectric loss of the insulating layer 1d tends to be large. Therefore, the relative permittivity of the dielectric powder is preferably in the range of 100 to 5,000.

The average particle size of the dielectric powder is determined by the thickness of the insulating layer.
It is preferably 0.1 μm or more from the viewpoint of the heat resistance of 1d, and preferably 15 μm or less, and more preferably 0.3 to 10 μm, from the viewpoint of the smoothness of the surface of the insulating layer 1d. .

Examples of the organic material having anisotropic dielectric properties include phenol resin, epoxy resin, polyimide resin, unsaturated polyester resin, triazine resin such as bismaleimide-triazine resin, and polyphenylene subjected to thermosetting denaturation. Thermosetting resins such as ether resins, and thermoplastics such as polyethylene, polystyrene, polycarbonate, polyethylene terephthalate, polyamide, polystyrene sulfide, polyethylene naphthalate, polyallyl sulfone, polyallyl ether ketone, liquid crystal polyester, and polyphenylene ether resins A resin is used, and a liquid crystal polymer represented by a liquid crystal polyester is preferable from the viewpoint of moisture resistance and dimensional accuracy.

The insulating layer 1d has, for example, an average particle diameter of 0.1 to 1
5μm low barium titanate or calcium titanate
Thermosetting resins such as epoxy resin, phenolic resin, polyimide resin, bismaleimide resin, thermosetting polyphenylene ether resin, or liquid crystal polyester / polyphenylene ether based dielectric powder such as barium stannate / barium zirconate / strontium zirconate A thermoplastic resin such as a resin, and a paste obtained by adding an appropriate solvent, plasticizer, dispersant, and the like are formed into a sheet by employing a conventionally known sheet forming method such as a doctor blade method.
By heating at a temperature of 100 ° C. for 5 minutes to 3 hours, a semi-cured precursor sheet to be the insulating layer 1d of the insulating substrate 1 is obtained, and a plating method or a metal foil is applied to the upper and lower surfaces of the semi-cured precursor sheet. A metal electrode is adhered by using a transfer method for transferring, and a DC voltage of 1 to 20 KV / mm is applied between the metal electrodes at a temperature of 60 to 100 ° C. for 30 minutes to 24 hours, thereby forming molecules of the organic material. Is oriented in the direction to which a DC voltage is applied, and finally, the metal electrode is removed by etching or lapping, whereby a precursor sheet serving as the insulating layer 1d of the insulating substrate 1 having a dielectric constant of 30 or more in the vertical direction is manufactured. You.

In general, molecules of an organic material have a rod-like shape and have a dipole moment. When a high DC voltage is applied to the molecules of the organic material from the outside, the direction of the dipole moment is substantially the same. When aligned and aligned, a large relative dielectric constant is exhibited in the direction in which the molecules are aligned. Furthermore, the dielectric powder contained in the insulating layer 1d in such a state that the molecules of the organic resin are oriented tends to easily align the dipole moment in the same direction. The relative dielectric constant of the insulating layer 1d in the direction in which the dipole moments of the molecules are aligned can be set to 1/100 to 1/2 of the relative dielectric constant of the dielectric powder. Insulation layer 1
If the relative permittivity of d is less than 1/100 of the relative permittivity of the dielectric powder, it tends to be difficult to obtain a high relative permittivity of 30 or more. Tend to be large. Therefore, the relative dielectric constant of the insulating layer 1d in the direction in which the dipole moment directions of the molecules of the organic material are aligned is 1/100 to the relative dielectric constant of the dielectric powder.
Preferably it is 1/2.

The term "orientation site" here mainly means a rigid P-substituted aromatic ring or a linear biphenyl, cyclohexyl- or substituted naphthyl-based aromatic ring. By having an orientation site of
The molecules have an elongated rod-like or plate-like shape and have good orientation.

The organic material used for the insulating layer 1d is as follows:
It is preferable that the molecule has an oriented site and that the ratio ε _P / ε _V of the relative dielectric constant ε _P in the principal axis direction of the molecule and the relative dielectric constant ε _{V in} the direction orthogonal to the principal axis direction be 1.2 to 10.

When the organic resin does not have an oriented portion, it becomes difficult to orient the organic resin satisfactorily, and it tends to be difficult to obtain a high relative dielectric constant of 30 or more. Therefore, the organic material used for the insulating layer 1d preferably has an oriented site in the molecule. In addition, when the ratio ε _P / ε _V of the relative permittivity ε _P of the molecules of the organic material in the main axis direction and the relative permittivity ε _V in the direction orthogonal to the main axis direction is less than 1.2, the organic material is well oriented. Tends to be difficult, and as a result, it is difficult to obtain a high relative dielectric constant of 30 or more, and if it exceeds 10, the degree of orientation of the molecules of the organic material becomes too large, and the reliability of the temperature cycle test etc. There is a tendency that cracks are generated or broken along the direction in which the molecules of the organic resin are oriented due to the stress generated at the time of thermal expansion and thermal contraction of the insulating layer 1d in the performance test. Therefore, the ratio ε _P / ε _V of the relative permittivity ε _P of the molecule in the principal axis direction to the relative permittivity ε _{V in} the direction orthogonal to the principal axis direction is 1.2.
It is preferably in the range of 10 to 10.

The term "major axis direction of a molecule" refers to a direction in which the relative dielectric constant of the molecule is the highest, and is usually the direction of the main chain in which atoms in the molecule are the longest. Further, the direction orthogonal to the molecule indicates all directions orthogonal to each other.

The insulating layers 1a, 1a constituting the insulating base 1
In b, 1c, 1d, and 1e, the insulating layers 1a, 1b, and 1b serving as the insulating base 1 are provided for the purpose of increasing the affinity between the organic material and the inorganic insulating powder, improving the bonding properties thereof, and increasing the mechanical strength of the insulating base 1. 1c,
One or more coupling agents such as a silane coupling agent and a titanate coupling agent may be added to 1d and 1e.

The same resin and hardener as the resin and hardener forming the precursor sheet forming the insulating layer 1d are used as the resin forming the precursor sheet forming the insulating layers 1a, 1b, 1c and 1e. By doing so, it becomes possible to simultaneously heat-cure the precursor sheet to be the insulating layer 1d and the precursor sheet to be the insulating layers 1a, 1b, 1c, and 1e under the same curing conditions,
Thus, the insulating layer 1d sandwiched between the opposing electrodes 3 for forming the capacitive element can be integrally formed in the insulating base 1 without any special difficulty.

Such an insulating substrate 1 includes copper, silver, and gold that pass through the insulating layers 1b, 1c, 1d, and 1e from the upper surface of the insulating layer 1b and pass through the insulating layers 1b, 1c, 1d, and 1e to the lower surface of the insulating layer 1e. A wiring conductor 2 is formed by bonding a metal powder such as an epoxy resin or the like with an organic material such as a thermosetting resin such as an epoxy resin or a thermoplastic resin such as a polyphenylene ether-based resin.

The wiring conductor 2 serves to electrically connect the semiconductor element 4 housed therein to an external electric circuit, and the electrode of the semiconductor element 5 (power supply electrode Ground electrode / signal electrode) is bonding wire 7
Are electrically connected to each other, and a portion extending to the lower surface of the insulating layer 1e is electrically connected to a wiring conductor of an external electric circuit board.

The metal powder contained in the wiring conductor 2 has an effect of imparting conductivity to the wiring conductor 2, and when the content in the wiring conductor 2 is less than 70% by weight, the conductivity of the wiring conductor 2 tends to decrease. If the content exceeds 95% by weight, it tends to be difficult to firmly bond the metal powder with a thermosetting resin or a thermoplastic resin. Therefore, the wiring conductor 2
Is preferably in the range of 70 to 95% by weight.

The wiring conductor 2 is made of insulating layers 1a, 1b, 1c, 1d, 1e as thermosetting resin or thermoplastic resin contained therein.
By using the same resin as the thermosetting resin or the thermoplastic resin contained in the insulating layer, the insulating layers 1a, 1b, 1c, 1d, and 1e can be satisfactorily adhered and formed.

Further, the wiring conductor 2 may be provided with a metal having excellent corrosion resistance, such as nickel or gold, and a good conductivity by a plating method to a thickness of 1.0 to 20 μm on the exposed surface. Can be effectively prevented, and the wiring conductor 2 and the bonding wire 7 can be firmly electrically connected. Therefore, on the exposed surface of the wiring conductor 2, a metal having excellent corrosion resistance and good conductivity, such as nickel or gold, is applied by plating to a thickness of 1.0 to 20 μm.
It is preferable that the film is adhered to a thickness of 10 mm.

When the metal powder contained in the wiring conductor 2 is copper and the organic material is an epoxy resin, for example, the copper powder having a particle size of about 0.1 to 10 μm is added to the wiring resin 2 by epoxy resin and amine curing. A paste is added to a semi-cured sheet serving as the insulating base 1 in a predetermined pattern by using a well-known screen printing method or the like. The semi-cured sheet is heat-cured together with the semi-cured sheet to be formed at a predetermined position on the insulating substrate 1.

Further, a pair of opposing electrodes 3 are disposed inside the insulating base 1 with the insulating layer 1 d interposed therebetween, and one of the pair of opposing electrodes 3 is connected to the power supply electrode of the semiconductor element 5 of the wiring conductor 2. The other end of the wiring conductor 2 is electrically connected to the wiring conductor 2 connected to the ground electrode of the semiconductor element 5.

The pair of opposing electrodes 3 are made of, for example, a metal powder such as copper, silver, or gold bonded by a thermosetting resin or a thermoplastic resin. It functions to form a capacitance element having a capacitance according to the thickness of the insulating layer 1d.

Since the insulating layer 1d sandwiched between the opposing electrodes 3 has a high dielectric constant of 30 or more as described above, a capacitive element having an extremely large capacitance is formed between the opposing electrodes 3. The malfunction of the semiconductor element 5 can be effectively prevented by the capacitive element having the large capacitance. In addition, by increasing the relative dielectric constant of the insulating layer 1d by changing the type of dielectric powder contained in the insulating layer 1d, the area of the counter electrode 3 can be reduced, and the size of the wiring board 4 can be reduced. It becomes possible.

The metal powder contained in the counter electrode 3 acts to impart conductivity to the counter electrode 3, and when the content in the counter electrode 3 is less than 70% by weight, the conductivity of the counter electrode 3 tends to decrease. If the content exceeds 95% by weight, it tends to be difficult to firmly bond the metal powder with a thermosetting resin or a thermoplastic resin. Therefore, the counter electrode 3
Is preferably in the range of 70 to 95% by weight.

The wiring conductor 2 and the counter electrode 3 formed on the surface of the insulating layers 1a, 1b, 1c, 1d, 1e may be formed of a metal foil made of copper, gold, or the like. , 1c, 1d, and 1e may be previously formed on the precursor sheet by a transfer method or the like.

Further, the semiconductor element 5 is bonded and fixed to the bottom surface of the concave portion A of the insulating base 1 with an adhesive such as resin, glass, brazing material or the like, and each electrode of the semiconductor element 5 is bonded via the bonding wire 7 to the concave portion A. Then, the semiconductor element 5 is hermetically sealed in the recess A with the lid 8 to provide an electronic component as a product.

Thus, according to the present invention, since the wiring board 4 is formed by bonding the inorganic insulating powder with the organic material having excellent toughness, the wiring board 4 having good impact resistance can be obtained. Further, since the opposing electrode 3 is disposed between the upper and lower surfaces of the insulating layer having a relative dielectric constant of 30 or more, a capacitive element having a large capacitance can be formed between the opposing electrodes 3, and a small electronic component 6 can be formed. It can be.

The wiring board of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. Although the wiring board is manufactured by stacking the insulating layers, the wiring board may be manufactured by stacking four or less insulating layers or six or more insulating layers. Insulating layer 1
As a reinforcing material to increase the strength of a, 1b, 1c, 1d, 1e, an inorganic filler such as glass fiber or silicon oxide / aluminum oxide / aluminum nitride is added to the insulating layers 1a, 1b, 1c, 1d, 1e. Is also good. The inorganic filler is the insulating layer 1a, 1
It has the effect of reinforcing the strength of b, 1c, 1d, and 1e and smoothing the surface, and is preferably a substantially spherical powder having an average particle diameter of 10 μm or less.

Further, a light stabilizer such as an antioxidant for improving thermal stability and an ultraviolet absorber for improving light resistance, and a halogen-based or phosphoric-based flame retardant for improving flame retardancy. Agents, antimony compounds, flame retardant aids such as zinc borate, barium metaborate and zirconium oxide, higher fatty acids and higher fatty acid esters to improve lubricity.
One or more compounds having an external lubricant hardening such as a higher fatty acid metal salt or a fluorocarbon surfactant may be added.

[0054]

According to the wiring board of the present invention, since the insulating base is formed by bonding inorganic insulating powder or dielectric powder with an organic material having excellent toughness, the wiring boards or the wiring board and the semiconductor are formed. No chipping, cracking, or cracking occurs in the insulating substrate even when a part of the automatic device manufacturing line collides violently.In addition, between the upper and lower surfaces of the insulating layer made of a composite member with a relative dielectric constant of 30 or more Since at least a pair of opposed electrodes is provided, a capacitor having a large capacitance can be obtained between the pair of opposed electrodes.

According to the electronic component of the present invention, it is not necessary to increase the area of the counter electrode more than necessary in order to obtain a large capacitance.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an electronic component when a semiconductor element is mounted as an electronic element on a wiring board according to the present invention.

[Explanation of symbols]

1 ... insulating base 1a, 1b, 1c, 1e ... insulating layer 1d ... relative dielectric constant in the vertical direction Is 30
The above insulating layer 2 ... wiring conductor 3 ... counter electrode 4 ... wiring board 5・ ・ ・ ・ ・ Semiconductor devices 6 ・ ・ ・ ・ Electronic components

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/46 H01L 23/14 RF term (Reference) 4E351 AA01 AA07 BB01 BB03 BB24 BB29 BB31 DD48 GG02 4J002 BB031 BC031 BH021 CC031 CD001 CF061 CF081 CF211 CG001 CH071 CH091 CL001 CM031 CM041 CN011 CN031 DE086 DE096 DE136 DE146 DF006 DJ006 GQ05 5E346 AA12 AA13 AA15 AA23 AA38 BB02 BB03 BB04 BB16 HBB BB20 CC08 CC16 DD21

Claims (3)

[Claims] 1 to 10% by weight of inorganic insulating powder and 30% by weight.
To 90% by weight of an organic material, and a plurality of insulating layers formed by bonding the inorganic insulating powder with the organic material. The insulating layers are vertically stacked, and a wiring conductor is formed on the insulating layer and / or on the surface of the exposed insulating layer. A wiring substrate formed by attaching the insulating layer, wherein at least one of the insulating layers has a relative dielectric constant of 30 or more in the upper and lower surface directions, and at least one pair of opposing electrodes is disposed between upper and lower surfaces thereof. Characteristic wiring board. 2. The insulating layer having a relative dielectric constant of 30 or more in the upper and lower surface directions comprises 10 to 70% by weight of dielectric powder and 30 to 90% by weight.
% By weight of an organic material having anisotropic dielectric property, and the relative permittivity in the direction in which the relative permittivity is the maximum is 1/100 to 1/2 of the relative permittivity of the dielectric powder. The wiring board according to claim 1, wherein: 3. An electronic component, comprising: the wiring board according to claim 1; and an electronic element mounted on the wiring board and electrically connected to the wiring conductor.