JP2003040670A - High thermal expansion porcelain composition, high thermal expansion porcelain, method of manufacturing the same, multilayer wiring board and mounting structure thereof - Google Patents

Abstract

(57) Abstract: A high thermal expansion porcelain made of a composite composition of a glass containing BaO and a filler, having a low dielectric constant, excellent chemical resistance and strength, and a high dielectric constant using the porcelain. A multilayer wiring board that is laminated with layers and has excellent mounting reliability over a long period of time is obtained. A metallized wiring layer (3) is disposed on the surface and / or inside of an insulating substrate (1).
a and a high dielectric constant layer 1b, a low dielectric constant layer 1a, a BaO of 5 to 6
20 to 80% by volume of a glass containing 0% by weight and 20 to 80% by volume of an inorganic filler, wherein the inorganic filler has a linear thermal expansion coefficient at 40 ° C. to 400 ° C. of 6 ppm.
The linear thermal expansion coefficient at 40 ° C. to 400 ° C. obtained by calcining a composition containing 20 to 99% by weight of a metal oxide of at least / ° C. and 1 to 80% by weight of cordierite is 8 to 15 p.
It is composed of a high thermal expansion porcelain having a relative dielectric constant of less than 7 at pm / ° C. and 1 MHz.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a porcelain composition having a high thermal expansion property, a porcelain and a method for manufacturing the same, a multilayer wiring board used for a package for storing a semiconductor element, which uses it as an insulating substrate, and its mounting. It is about structure.

[0002]

2. Description of the Related Art Conventionally, a multilayer wiring board has a structure in which a metallized wiring layer is provided on the surface or inside of an insulating substrate in which insulating layers are laminated in multiple layers.
And other semiconductor element housing packages. As such a package, a package in which an insulating layer is made of ceramics such as alumina is often used, and more recently, a package in which a low temperature fired porcelain capable of simultaneous firing with copper metallization is used as an insulating substrate has been put into practical use.

In such a ceramic multilayer wiring board, the number of connection terminals for connecting to an external circuit board such as a printed circuit board tends to increase as the degree of integration of semiconductor elements increases. As the BGA, a ceramic multi-layer wiring board having a spherical connection terminal made of solder attached to the lower surface thereof is used. This BGA is
The connection terminal is placed on the wiring conductor on the external circuit board, and the connection terminal is melted and connected by heat treatment at a temperature of 250 to 400 ° C.

However, in this mounting method, when conventional ceramics such as alumina and mullite are used, the coefficient of linear thermal expansion of the ceramic circuit board is about 4 to 7 × 10 ^-6.
/ ° C., Whereas the linear thermal expansion coefficient of a printed circuit board using a glass-epoxy insulating layer for soldering the substrate is about 11 to 18 × 10 ⁻⁶ / ° C. There is a problem that a large thermal stress is generated due to the difference in thermal expansion between the ceramic multilayer wiring board and the external circuit board due to the heat. The thermal stress has a greater effect as the number of connection terminals increases, and the thermal stress is applied to the connection terminals by repeating the operation and stop of the semiconductor element,
There is a problem that the connection terminal is separated from the wiring conductor.

In order to solve such a problem, the applicant of the present invention has previously proposed that a high thermal expansion porcelain obtained by mixing a predetermined filler with a high thermal expansion glass and firing the glass is used as an insulating substrate.

On the other hand, with the rapid spread of portable information terminals such as mobile phones and notebook computers, there is a strong demand for downsizing of electronic components mounted therein. As an example, a switching circuit and a power amplifier circuit of a mobile phone are composed of a plurality of resistors and capacitors, and conventionally, these elements are individually installed on a circuit board, which hinders miniaturization and reduction of manufacturing cost. Was becoming.

[0007]

In order to reduce the size of electronic components mounted on portable electronic equipment, not only ceramic wiring boards that house semiconductor elements but also printed circuit boards and the like on which the wiring boards are mounted are mounted. It is necessary to downsize the external circuit board. However, conventionally, since the ceramic wiring board, the capacitor, and the resistor are individually mounted on the external circuit board, there are problems that miniaturization is difficult and manufacturing cost for mounting is high.

Therefore, there has been proposed a capacitor-embedded substrate in which a ceramic layer having a high dielectric constant is provided inside a ceramic multilayer wiring substrate. As a dielectric material having a high dielectric constant, a composite perovskite-based dielectric material mainly composed of BaO—TiO ₂ system, PbO—TiO ₂ system, etc. has been conventionally known, and such a dielectric material is a low temperature fired porcelain. There was a problem that it was not possible to perform simultaneous firing.

Therefore, the applicant of the present invention previously contained BaO.
High thermal expansion glass and BaTiO ₃, CaTiO₃Etc.
High thermal expansion obtained by adding a high dielectric constant filler component and firing
Zhang, proposed a high-permittivity porcelain, and
Stacking the container with the low-k layer and placing the
We proposed a multilayer wiring board with a built-in capacitor that draws out the capacity.
It was

In this case, the low dielectric constant layer has a high dielectric constant in order to control the contraction rate when co-firing with the high dielectric constant layer and the diffusion between different materials. It is desired that it consists of the same glass as the layer.

However, when a porcelain using a glass having a low softening point and a high thermal expansion containing BaO is to be used as the low dielectric constant layer, the relative dielectric constant cannot be lowered or the chemical resistance is poor, and the plating process, etc. There was a problem that the porcelain was discolored or the strength was low when it was treated with an acidic solution or an alkaline solution used in.

Therefore, the present invention comprises a composite composition of a glass containing BaO and a filler, and has a high thermal expansion porcelain composition and a high thermal expansion porcelain excellent in low dielectric constant, chemical resistance and strength, and the production thereof. It is intended to provide a method.

The present invention also provides a multilayer wiring board using the above-mentioned high thermal expansion porcelain, particularly a multilayer wiring board laminated with a high dielectric constant layer, and a mounting structure excellent in long-term stability. It is intended.

[0014]

Means for Solving the Problems As a result of repeated studies on the above problems, the present inventors have combined BaO-containing glass with a filler having high thermal expansion and a cordierite at a predetermined ratio as fillers. The present inventors have found that it is possible to improve the dielectric constant, chemical resistance and strength of the porcelain as well as increase the thermal expansion of the porcelain.

That is, the high thermal expansion porcelain composition of the present invention comprises B
It is composed of 20 to 80% by volume of glass containing 5 to 60% by weight of aO and 20 to 80% by volume of inorganic filler, and the inorganic filler has a linear thermal expansion coefficient of 6 ppm / ° C or more at 40 ° C to 400 ° C. 20 to 99% by weight of the metal oxide and 1 to 80% by weight of cordierite, respectively, and the composition has a linear heat at 40 ° C. to 400 ° C. after firing. The expansion coefficient is 8 to 15 ppm / ° C., and the relative dielectric constant at 1 MHz is less than 7.

Further, the high thermal expansion porcelain of the present invention is produced by molding and firing the above composition, and is composed of a crystal phase and a glass phase, and the crystal phase is 40 ° C. to 400 ° C. Linear thermal expansion coefficient at 6 ℃ is 6ppm / ℃
With the above metal oxides, mainly formed in Celsian,
The amount of BaO in the glass phase is 10 wt% or less, 4
Coefficient of linear thermal expansion at 0 ° C to 400 ° C is 8 to 15 ppm
It is characterized in that the relative dielectric constant at / ° C. and 1 MHz is less than 7, and the Celsian is preferably a hexagonal Celsian having an average aspect ratio of 3 or more in order to achieve high strength.

Further, the method for manufacturing a high thermal expansion porcelain of the present invention comprises 20 to 8 of glass containing 5 to 60% by weight of BaO.
0% by volume and 20-80% by volume of an inorganic filler, wherein the inorganic filler has a coefficient of linear thermal expansion at 40 ° C. to 400 ° C. of 6 to 9 ppm / ° C. or higher and a metal oxide of 20 to 9%.
After molding a composition containing 9% by weight and cordierite at a ratio of 1 to 80% by weight, respectively, 800 ° C. to 1100 ° C.
In particular, after the composition is molded, the composition is temporarily held at a temperature lower than the optimum baking temperature within a temperature range of 750 to 900 ° C.
Firing at an optimum firing temperature of ℃ to 1100 ℃ is desirable for precipitating Celsian.

Furthermore, according to the present invention, in a multilayer wiring board in which a metallized wiring layer is provided on the surface and / or inside of an insulating substrate in which ceramic insulating layers are laminated in multiple layers, at least one of the ceramic insulating layers is provided. One layer is formed by a low dielectric constant layer made of the high thermal expansion porcelain, and at least one of the ceramic insulating layers has a linear thermal expansion coefficient of 8 to 1 at 40 to 400 ° C.
The relative dielectric constant at 5 ppm / ° C. and 1 MHz is 10 or more, and further, the glass containing BaO and the linear thermal expansion coefficient at 40 to 400 ° C. as a crystal phase are 8 ppm /
It is preferable that the high dielectric constant layer includes a metal oxide having a relative dielectric constant of 40 or more at 1 ° C. or higher at a temperature of 1 ° C. or higher. By disposing the high dielectric constant layer between a pair of electrode layers, a high dielectric constant layer is provided between the pair of electrodes. A predetermined capacitance can be extracted.

Further, in the above multilayer wiring board, the difference in linear thermal expansion coefficient between the low dielectric constant layer and the high dielectric constant layer at 40 to 400 ° C. is 0.5 ppm / ° C. or less. It is desirable to prevent peeling of the film.

Further, the above-mentioned multilayer wiring board is one in which a semiconductor element is mounted on the surface of the insulating substrate, and a connection terminal for connecting to an external circuit is provided on the back surface of the insulating substrate, and at least an organic resin is used. The multilayer wiring board is placed on an external circuit board having wiring conductors adhered to the surface of an insulating body, and the connection terminals of the multilayer wiring board and the wiring conductors are brazed to each other, thereby forming a multilayer wiring board. Can be mounted on an external circuit board, but according to the present invention,
Since the coefficient of thermal expansion of the multilayer wiring board is similar to that of the external circuit board, it has high mounting reliability even when the connection terminals are ball-shaped terminals.

[0021]

The high thermal expansion porcelain composition of the present invention comprises:
20 to 80% by volume of glass containing 5 to 60% by weight of BaO and 20 to 80% by volume of inorganic filler,
The inorganic filler contains a metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or higher at 40 ° C. to 400 ° C. of 20 to 99% by weight and cordierite at a ratio of 1 to 80% by weight, respectively. .

The amount of metal oxide and cordierite having a linear thermal expansion coefficient of 6 ppm / ° C. or more at 40 ° C. to 400 ° C. contained in the filler is limited to the above range at 40 ° C.
If the amount of the metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or more at ˜400 ° C. is less than 20% by weight or the amount of cordierite is more than 80% by weight, the porcelain obtained after firing has a temperature of 40 ° C. to 400 ° C. It becomes difficult to increase the linear thermal expansion coefficient at 8 ° C to 8 ppm / ° C or higher. Also, 4
If the amount of metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or more at 0 ° C. to 400 ° C. is more than 99% by weight or the amount of cordierite is less than 1% by weight, the dielectric constant of the obtained porcelain at 1 MHz is obtained. It becomes difficult to make the rate less than 7, or the chemical resistance is poor and the porcelain becomes discolored when treated with an acidic solution or an alkaline solution used in the plating process, or the strength is low. This is because Particularly, the amount of metal oxide is preferably 35 to 95% by weight, and the amount of cordierite is preferably 5 to 65% by weight. The above metal oxide and cordierite are contained in the filler in a total amount of 80% by weight or more, particularly 90% by weight or more, and further 95% by weight or more.

Further, according to the present invention, B in the glass is
It is important that the aO content is 5 to 60% by weight.
When the BaO content is less than 5% by weight, it becomes difficult to soften the glass and the linear thermal expansion coefficient becomes low, and the linear thermal expansion coefficient of the obtained porcelain at 40 ° C to 400 ° C is 8 ppm / ° C or more. It becomes difficult to raise it, and B
If the amount of aO is more than 60% by weight, vitrification is difficult and the characteristics tend to be unstable.
It becomes difficult to make the relative dielectric constant at less than 7 at MHz, or the chemical resistance is poor, and the porcelain becomes discolored when treated with an acidic solution or an alkaline solution used in the plating step, etc. Alternatively, the strength becomes low.

According to the present invention, the glass and the filler are mixed in an appropriate ratio according to the purpose such as the firing temperature and the thermal expansion characteristics of the finally obtained porcelain. The glass used in the present invention has a shrinkage initiation temperature of 700 ° C. or lower without adding a filler and melts at 850 ° C. or higher, so that a metallized wiring layer and the like cannot be disposed. However, by mixing the filler, crystals are precipitated during the firing process, and a liquid phase for liquid-phase sintering the filler can be formed at an appropriate temperature. Further, since the shrinkage start temperature of the entire compact can be raised, by adjusting the content of such filler, it is possible to match the simultaneous firing conditions with the metallized wiring layer depending on the type of metallization used.

In the high thermal expansion ceramic composition of the present invention, the glass amount is 20 to 80% by volume and the filler amount is 80%.
It is mixed at a ratio of 20% by volume. The amount of the glass and the filler is limited to the above range because the amount of the glass is less than 20% by volume, in other words, the amount of the filler is 8%.
If it is more than 0% by volume, it is difficult to perform liquid phase sintering, the firing temperature becomes high, and the metallized wiring layer may be melted at the time of simultaneous firing with the metallized wiring layer. Further, when the glass amount is more than 80% by volume, in other words, when the filler amount is less than 20% by volume, the characteristics of the porcelain largely depend on the characteristics of the glass, and it becomes difficult to control the material characteristics, and the sintering start temperature becomes low. Therefore, there is a problem in that co-firing with the metallized wiring layer becomes difficult because of the low value. Also,
The cost of raw materials tends to increase due to the large amount of glass.

Further, it is desirable that the amount of the filler is appropriately adjusted according to the yield point of the glass. That is, when the yield point of the glass is as low as 400 ° C. to 700 ° C., the sinterability at low temperature is enhanced, so that the filler amount is 40 to 80% by volume.
Can be mixed in relatively large amounts On the other hand, when the deformation point of the glass is as high as 700 ° C. to 800 ° C., the sinterability is lowered, so that it is desirable to mix the filler in a relatively small amount of 20 to 50% by volume.

In the above composition, as one of the filler components, as a coloring component, chromium oxide, cobalt oxide, manganese oxide, nickel oxide, iron oxide, copper oxide,
You may mix | blend at least 1 sort (s) selected from the group of barium chromate and a silicon | silicone by the ratio of 10 weight% or less.

According to the above-mentioned high thermal expansion porcelain composition of the present invention, a mixture of this composition is molded and then 800 to 1100 ° C.
By firing at, the cordierite reacts with the BaO component of the glass, resulting in the formation of Celsian and the reduction of the BaO component of the balance glass phase, resulting in a decrease in the permittivity of the balance glass phase in the porcelain and resistance to The chemical properties can be improved. As a result, the obtained porcelain has a low dielectric constant, excellent chemical resistance, and can suppress the occurrence of discoloration due to treatment with an acidic solution or an alkaline solution.

That is, the high thermal expansion porcelain of the present invention obtained by firing the above composition is composed of a crystal phase and a glass phase, and the crystal phase is 40 ° C. to 4 ° C.
A metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or higher at 00 ° C. and a metal oxide are mainly formed in Sergian. In particular, when the Sergian is precipitated as hexagonal Sergian with an average aspect ratio of 3 or more, and the hexagonal Sergian crystals are dispersed in the porcelain, the fracture toughness is improved due to deflection of crack propagation in the porcelain. However, the strength of the porcelain increases.

Another major feature is that the amount of BaO in the glass phase in this porcelain is 10% by weight or less. That is, when the amount of BaO in the glass phase is large, the porcelain formed by this has a high relative dielectric constant and poor chemical resistance, but the amount of BaO is controlled to 10% by weight or less. As a result, the relative dielectric constant can be reduced and the chemical resistance can be improved.

Further, the porcelain of the present invention has a high thermal expansion coefficient of linear thermal expansion of 8 to 15 ppm / ° C. at 40 ° C. to 400 ° C. and a relative dielectric constant of less than 7 at 1 MHz, due to the above-mentioned structure. It is made of low-permittivity porcelain.

The high thermal expansion porcelain composition and high heat
In expansion porcelain, the coefficient of linear thermal expansion is 6ppm / ℃ or more
As the metal oxide, quartz (SiO₂, Cristoba
Light (SiO₂), Tridymite (SiO₂),
Stellite (2MgO ・ SiO₂), Spinel (MgO
・ Al₂O₃), Wollastonite (CaO ・ Si
O₂), Monticellanite (CaO ・ MgO ・ Si
O₂), Nepheline (Na₂O ・ Al₂O₃・ SiO₂),
Diopside (CaO ・ MgO ・ 2SiO₂), Melbi
Night (3CaO ・ MgO ・ 2SiO₂), Akermai
G (2CaO ・ MgO ・ 2SiO₂), Magnesia (M
gO), alumina (Al₂O₃), Carnegiaite (Na
₂O ・ Al₂O₃・ 2SiO₂), Enstatite (MgO
・ SiO₂), Magnesium borate (2MgO · B
₂O₃), Sergian (BaO ・ Al₂O₃・ 2Si
O ₂), B₂O₃・ 2MgO ・ 2SiO₂, Garnite (Z
nO / Al₂O₃) At least one selected from the group
You can Among these, quartz and Cristobalai
SiO such as grit and tridymite₂Materials and forste
At least one selected from the group of light and enstatite
Seeds are desirable for achieving high thermal expansion.

In the present invention, the specific manufacturing method for obtaining the above-mentioned high thermal expansion porcelain is first suitable for the mixture of glass and filler as described in the above-mentioned high thermal expansion porcelain composition. After adding an organic resin binder for molding, a desired molding means, for example, a die press, cold isostatic pressing, injection molding, extrusion molding, doctor blade method, calender roll method, rolling method, etc., into an arbitrary shape. It shape | molds and the obtained molded object is baked. In firing, first, the binder component blended for molding is removed. The binder is removed at 500 to 800 ° C. in the atmosphere or nitrogen atmosphere. At this time, the shrinkage starting temperature of the molded body is preferably about 700 to 850 ° C. If the shrinking starting temperature is lower than this, it becomes difficult to remove the binder.

When a wiring board is prepared, a slurry is prepared by adding and mixing an appropriate organic binder, solvent and plasticizer to the above mixture of glass and filler, and the slurry is well known. By the green sheet molding method by the coating method such as doctor blade of
Make a green sheet. Further, a metal paste obtained by adding and mixing an organic binder, a plasticizer, and a solvent to a metal powder made of one or more of copper, silver, nickel, palladium, and gold is predetermined on the green sheet by a known screen printing method. Apply the pattern by printing. In some cases, the green sheet is appropriately punched to form a via hole, and the metallizing paste is filled in the via hole. Then, a plurality of these green sheets are laminated and pressure-bonded, and then fired. During firing, the binder component mixed for molding is removed, but the binder is removed at 100 to 800 ° C. when copper is used as the wiring conductor forming the metallized wiring layer.
Is performed in a nitrogen atmosphere containing water vapor.

The firing is carried out in an oxidizing atmosphere or a non-oxidizing atmosphere, and in order to improve the strength of the porcelain, it is 75
After the needle-like or columnar hexagonal Celsian crystal is temporarily maintained at a temperature lower than the optimum firing temperature within a temperature range of 0 to 900 ° C., and then performed at the optimum firing temperature of 800 ° C. to 1100 ° C. Is desirable. The optimum firing temperature is 80
If it is lower than 0 ° C., it cannot be densified, and if it is higher than 1100 ° C., it becomes difficult to co-fire with the metallized wiring layer.
However, when copper is used as a component of the wiring conductor,
It is desirable to perform firing in a non-oxidizing atmosphere at 0 to 1000 ° C.

FIG. 1 shows an example in which the high thermal expansion porcelain of the present invention is applied as a low dielectric constant layer. It shows a wiring board, especially a BGA (ball grid array) type semiconductor element housing package and its mounting structure. It is a schematic sectional drawing which shows one Example. This package has a basic structure of a so-called wiring board in which a metallized wiring layer is provided on the surface or inside of an insulating substrate. A indicates a semiconductor element housing package and B indicates an external circuit board.

The semiconductor element housing package A is composed of an insulating substrate 1, a lid body 2, a metallized wiring layer 3 and a connecting terminal 4, and the insulating substrate 1 and the lid body 2 hermetically house the semiconductor element 5 therein. To form the cavity 6. Then, in the cavity 6, the semiconductor element 5 is adhesively fixed to the insulating substrate 1 via an adhesive material such as glass or resin.

On the surface and inside of the insulating substrate 1,
The metallized wiring layer 3 is provided so as to be electrically connected to the semiconductor element 5 and the connection terminal 4 formed on the lower surface of the insulating substrate 1. According to the package of FIG. 1, the connection terminal 4 has a ball-shaped terminal 4b made of high-melting point solder (tin-lead alloy) attached by a brazing material via a connection pad 4a.

On the other hand, the external circuit board B is composed of an insulator 7 and a wiring conductor 8, and the insulator 7 is made of an insulating material containing at least an organic resin, specifically, a glass-epoxy composite material. As described above, the linear thermal expansion coefficient at 40 to 400 ° C. is 12 to 16 ppm / ° C., and a printed circuit board or the like is generally used. The wiring conductor 8 formed on the surface of the substrate B is usually made of copper, gold, or the like in terms of the matching of the thermal expansion coefficient with the insulator 7 and the good electrical conductivity.
It is made of a metal conductor such as silver, aluminum, nickel, or lead-tin.

In order to mount the semiconductor element housing package A on the external circuit board B, the ball-shaped terminals 4b on the lower surface of the insulating substrate 1 of the package A are placed on the wiring conductors 8 of the external circuit board B and brought into contact therewith. After that, the solder is melted at a temperature of about 250 to 400 ° C. with a brazing material such as low melting point solder, and the wiring conductor 8 and the ball-shaped terminal 4b are bonded to each other for mounting. At this time, the ball-shaped terminal 4 is formed on the surface of the wiring conductor 8.
It is desirable that the brazing material is previously formed by adhesion in order to facilitate the connection with b by the brazing material.

The insulating substrate 1 in this package A is
As shown in FIG. 1, a low dielectric constant layer 1a and a high dielectric constant layer 1b
Composed of and. The low dielectric constant layer 1a is made of the high thermal expansion ceramic of the present invention. In addition, the high dielectric constant layer 1b
Electrode layers 9 made of a metal conductor such as copper are formed on the upper and lower sides of the wirings and are connected to the metallized wiring layer 3 on the surface of the substrate via the via-hole conductors 10 and the like, so that a predetermined capacitance is provided between the wiring layers 3. You can take it out.

Such a high dielectric constant layer has a temperature of 40 to 400 ° C.
Coefficient of linear thermal expansion at 8-15ppm / ° C and 1M
It is desirable to use a high thermal expansion porcelain having a high thermal expansion and a high dielectric constant having a relative dielectric constant of 10 or more at Hz.

The high-thermal-expansion, high-dielectric-constant porcelain has a relative dielectric constant of 40 and glass containing BaO in an amount of 5 to 60% by weight, like the high-thermal-expansion porcelain composition for forming the low-dielectric constant layer of the present invention. It is desirable to be formed from the above high dielectric constant filler and a filler of a metal oxide having a thermal expansion coefficient at 40 to 400 ° C. of 8 pm / ° C. or more.

This is because the metal oxide is contained as a crystal phase of the high-thermal-expansion, high-dielectric constant porcelain after firing, and the high-thermal-expansion, high-dielectric constant porcelain 40-400 is included.
The linear thermal expansion coefficient at 8 to 15 ppm / ° C, and 1
This is because it becomes easy to set the relative dielectric constant at 10 MHz or higher. Examples of such metal oxides include, but are not limited to, titania (coefficient of linear thermal expansion: 9 ppm / ° C., relative dielectric constant: 80), calcium titanate (coefficient of linear thermal expansion: 13 ppm / ℃, ε = 18
0), strontium titanate (coefficient of linear thermal expansion: 9 pp
m / ° C, relative permittivity: 300), barium titanate (coefficient of linear thermal expansion: 14 ppm / ° C, relative permittivity: 13000),
At least one selected from the group of titania compounds such as lanthanum titanate (coefficient of linear thermal expansion: 15 ppm / ° C., relative dielectric constant: 45) can be used.

For this porcelain having a high dielectric constant and high thermal expansion, the same glass as that for forming the low dielectric constant layer 1a is used, and a high dielectric constant filler having a relative dielectric constant of 40 or more and 40 to 4 are used.
It can be prepared by mixing a composition with a filler of a metal oxide having a thermal expansion coefficient at 00 ° C. of 8 pm / ° C. or more and firing it. Particularly, in preparing a multilayer wiring board, the low dielectric constant layer 1 a The composition for the high dielectric constant layer is formed, punched out, and printed with an electrode layer to produce a green sheet having a high thermal expansion and a high dielectric constant, and the low dielectric constant of the present invention. After laminating with the green sheet for the rate layer, the green sheet laminated body and the metallization are simultaneously fired to obtain a multilayer wiring board having a built-in capacitor.

The difference in linear thermal expansion coefficient between the low dielectric constant layer 1a and the high dielectric constant layer 1b at 40 to 400 ° C. is preferably 0.5 ppm / ° C. or less. If the difference in the linear thermal expansion coefficient is larger than 1 ppm / ° C., breakage is likely to occur in or between the low dielectric constant layer 1a and the high dielectric constant layer 1b in the firing step, and the linear thermal expansion coefficient difference is large. Is more than 0.5 ppm and 1 ppm / ° C. or less, co-firing is possible, but cracks may occur in the layers or between the layers. Therefore, in order to co-fire the low dielectric constant layer 1a and the high dielectric constant layer 1b and prevent the occurrence of cracks in the multilayer wiring board, the difference in linear thermal expansion coefficient between them is 0.5 p.
It is desirable to set it to pm / ° C. or less.

The adjustment of the thermal expansion is performed by adjusting the thermal expansion coefficient of the high thermal expansion porcelain forming the low dielectric constant layer 1a to the high dielectric constant layer 1b.
In order to match the linear thermal expansion coefficient of the high thermal expansion porcelain that forms the film, the filler component in the low dielectric constant layer 1a is 40 ° C.
It can be easily controlled by appropriately adjusting the contents of the metal oxide and the cordierite having a linear thermal expansion coefficient of 6 ppm / ° C. or more at ˜400 ° C.

According to the present invention, the high thermal expansion low dielectric constant layer 1a
And a high thermal expansion multilayer wiring board having a built-in capacitor of the present invention constituted by the high thermal expansion high dielectric constant layer 1b is mounted on a printed circuit board or the like containing an organic resin through solder ball-shaped terminals 4b or solder. Even in this case, since the coefficient of thermal expansion is similar to that of the external circuit board B, it is possible to implement long-term reliability with respect to the temperature cycle. Moreover, by incorporating the capacitor, it is possible to reduce the size of the external circuit board B such as a printed board on which the board is mounted.

[0049]

[Example] Example 1 As BaO-containing glass, SiO₂: 44 wt% -Al₂
O₃: 7 wt% -B₂O ₃: 14% by weight-CaO: 12 times
% -BaO: 23% by weight of glass A (yield point:
690 ° C), SiO₂: 37 wt% -Al₂O₃: 5 weight
% -B₂O₃: 13 wt% -CaO: 17 wt% -Ba
O: 25 wt% -ZrO₂: Glass B consisting of 3% by weight
(Yield point: 710 ° C), Quartz and foam as filler
Rosterite, cordierite, chromium oxide
They were prepared and weighed and mixed at the ratios shown in Table 1 and Table 2.
After crushing this mixture, add organic binder and organic solvent
And mix well to make slurry, doctor blade
A green sheet having a thickness of 300 μm was produced by the method.
50 m after laminating and pressing 8 sheets of the obtained green sheets
A sample of mx 50 mm was prepared and steam at 700 ° C was added.
860 after debinding process in nitrogen atmosphere containing
℃ × 1 hour + 910 ℃ × 1 hour firing in a nitrogen atmosphere
I went.

Next, for the porcelain obtained as described above, the linear thermal expansion coefficient at 40 to 400 ° C. and 1 MHz were used.
Was measured. Furthermore, the above porcelain was alkali-melted with sodium carbonate and dissolved in a hydrochloric acid solution, and Ba in the solution was analyzed by an ICP emission spectrophotometer, and BaO of the glass component was quantitatively evaluated from the obtained data. . The results are shown in Tables 1 and 2.

In addition, the above porcelain was replaced with 10 g of NH ₄ F.HF.
Was evaluated for presence or absence of change in color tone after dipping for 90 seconds in a hydrofluoric acid solution at room temperature dissolved in 1 L of water. The results are shown in Tables 1 and 2.

Further, when X-ray diffraction measurement was performed on the above-mentioned porcelain, the quartz crystal phase was found to be present in all of the samples to which quartz was added, and diopside and forsterite were found to be obtained in all of the samples to which forsterite was added. It was confirmed that the hexagonal Celsian crystal phase was present in all the samples to which cordierite was added. Then, the porcelain surface was sharply polished, and the average aspect ratio of the hexagonal Sergian crystal (major axis /
The minor axis was calculated to be 3 to 3 for any sample.
It was confirmed to be within the range of 10.

Subsequently, JISR16 was applied to the above porcelain.
Based on 01, the 4-point bending strength was measured. The results are shown in Tables 1 and 2. Example 2 Further, a green sheet having a thickness of 500 μm was produced by the doctor blade method using the composition of Example 1, and a copper metallizing paste was applied to the surface of the sheet by a screen printing method. Also, via holes were formed at predetermined locations on the green sheet, and copper metallizing paste was also filled in the via holes. Then, six green sheets coated with the metallizing paste were laminated between the through holes and pressure-bonded. After debinding the laminate in a nitrogen atmosphere containing water vapor at 700 ° C.,
The metallized wiring layer and the insulating substrate were co-fired in a nitrogen atmosphere at 860 ° C. × 1 hour + 910 ° C. × 1 hour to produce a wiring board.

Next, as shown in FIG. 1, a ball-shaped terminal made of 90% by weight of lead and 10% by weight of tin is attached to the electrode pad provided on the lower surface of the wiring board with low melting point solder (37% by weight of lead and 6% of tin).
3% by weight). The connection terminal is 1 cm
^It was formed on the entire lower surface of the wiring board with a density of 30 terminals per ² pieces.

This wiring board is mounted on the surface of a printed board having a wiring conductor made of copper foil formed on the surface of an insulator made of a glass-epoxy board and having a linear thermal expansion coefficient of 13 ppm / ° C. at 40 to 800 ° C. did. The mounting was performed by aligning the wiring conductors on the printed circuit board and the ball-shaped terminals of the wiring board, and connecting and mounting with a low melting point solder.

Next, the test sample was mounted on the surface of the printed circuit board for packaging as described above, and the test sample was placed in a constant temperature bath controlled at temperatures of -40 ° C. and 125 ° C. in the atmosphere for 15 minutes / Holding for 15 minutes was set as one cycle, and the cycle was repeated up to 1000 cycles. Then, the electric resistance between the wiring conductor of the printed circuit board and the package wiring board is measured for each cycle, and the number of cycles until a change in the electric resistance appears is measured. What was called NG. The results are shown in Tables 1 and 2. Example 3 Further, with respect to 50% by volume of glass A described in Example 1, 20% by weight of calcium titanate and 80% by weight of lanthanum titanate were added as a composition C (40 to 40% by weight).
Coefficient of linear thermal expansion at 400 ° C: 9.0 ppm / ° C, 1
20% by weight of calcium titanate and 80% by weight of lanthanum titanate as fillers with respect to relative dielectric constant in MHz: 18) and 50% by volume of glass B described in Example 1.
A composition D (40 to 400 ° C. linear thermal expansion coefficient: 9.5 ppm / ° C., relative permittivity at 1 MHz: 20) is prepared, and a green sheet is prepared in the same manner as in Example 1. did.

Next, three green sheets each consisting of the compositions shown in Tables 1 and 2 in Example 1 were laminated on the upper and lower sides of the above green sheet, and a total of 3 sheets were laminated and pressure-bonded, and then 50 mm ×
A sample of 50 mm is prepared, and after debinding in a nitrogen atmosphere containing water vapor at 700 ° C., 860 ° C. ×
Firing was performed in a nitrogen atmosphere for 1 hour + 910 ° C. × 1 hour.

Next, with respect to the wiring board obtained as described above, the interface between the high dielectric constant layer and the insulating layer was observed with a binocular microscope. The sample in which cracks were present was designated as Δ, and the sample in which peeling occurred during the firing stage was designated as ×. The results are shown in Tables 1 and 2.

[0059]

[Table 1]

[0060]

[Table 2]

As is clear from the results shown in Tables 1 and 2, the sample No. 7-19, 21-26, 29-3
3 has a linear thermal expansion coefficient of 8 at 40 ° C to 400 ° C.
The relative dielectric constant at -15 ppm / ° C and 1 MHz was less than 7. In addition, the balance glass phase BaO of the above sample
The component ratio was lower than that of the glass phase before firing, and it was excellent in resistance to hydrofluoric acid solution and strength.

According to the result of the heat cycle test, 4
The sample No. of the present invention having a coefficient of thermal expansion of 0 to 400 ° C. of 8 to 15 ppm / ° C. 7-19, 21-26, 29-33
The wiring board using was sufficiently resistant to the test up to 1000 cycles.

Further, the difference in linear thermal expansion coefficient from the high dielectric constant layer is 1
The sample No. of the present invention having a concentration of ppm / ° C. or less 12, 1
Sample Nos. 5 to 19, 24, 25, and 29 to 32, which had no peeling at the firing stage, had a difference of 0.5 ppm / ° C. or less. 16, 17, 25, 29, 30, 3
No. 2 generated no cracks even after the heat cycle test. In addition, sample No. outside the scope of the present invention. In No. 3 as well, simultaneous firing with the high dielectric layer was possible, but in such a sample, the relative permittivity at 1 MHz was 7 or more, and the resistance to the hydrofluoric acid solution was poor.

[0064]

As described in detail above, according to the present invention,
Since it is possible to obtain a porcelain excellent in low dielectric constant, chemical resistance, and strength, and further, it is possible to co-fire with high thermal expansion and high dielectric constant porcelain, it is possible to obtain a high thermal expansion with a built-in capacitor manufactured using this. The multilayer wiring board can be mounted with long-term reliability against temperature cycles even when mounted on a printed circuit board or the like containing an organic resin via ball-shaped terminals or solder. Moreover, since the multilayer wiring board with a built-in capacitor does not require the capacitor conventionally mounted on the external circuit board, it is effective for downsizing the external circuit board and reducing the mounting cost, and is rapidly spreading. It is expected to contribute greatly to the miniaturization of portable electronic devices.

[Brief description of drawings]

FIG. 1 is a schematic sectional view for explaining an embodiment of a multilayer wiring board of the present invention.

[Explanation of symbols]

1 Insulation board 1a Low dielectric constant layer 1b High dielectric constant layer 2 lid 3 Metallized wiring layer 4 connection terminals 4a electrode pad 4b Ball terminal 5 Semiconductor element 6 cavities 7 insulator 8 wiring conductors 9 electrode layers 10 Via hole conductor A Semiconductor element storage package B External circuit board

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05K 3/46 H01L 23/14 C (72) Inventor Yoji Kokubo 1-4 Yamashita-cho, Kokubun-shi, Kagoshima Kyocera Incorporated Research Institute F-term (reference) 4G030 AA07 AA08 AA10 AA17 AA22 AA35 AA36 AA37 BA12 BA21 CA01 CA04 CA08 GA03 GA04 GA14 GA17 GA20 GA24 GA28 HA01 HA09 HA18 5E346 AA12 AA13 AA43 BB16 CC18 CC21 CC32 DD13 DD34 EE

Claims (15)

[Claims] 1. A glass containing 5 to 60% by weight of BaO in an amount of 20 to 80% by volume and an inorganic filler in an amount of 20 to 80% by volume.
The inorganic filler contains 20 to 99% by weight of a metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C or more at 40 ° C to 400 ° C and 1 to 80% by weight of cordierite. A high thermal expansion porcelain composition characterized by: 2. A high thermal expansion ceramic composition according to claim 1, wherein the linear thermal expansion coefficient at 40 ° C. to 400 ° C. after firing is 8 to 15 ppm / ° C. and the relative dielectric constant at 1 MHz is less than 7. . 3. A crystalline phase and a glass phase, wherein the crystalline phase has a linear thermal expansion coefficient of 6 pp at 40 ° C. to 400 ° C.
m / ° C. or higher metal oxide and Cergian are mainly formed, the amount of BaO in the glass phase is 10 wt% or less, and the linear thermal expansion coefficient at 40 ° C. to 400 ° C. is 8 to 15
High thermal expansion porcelain having a relative dielectric constant of less than 7 at ppm / ° C. and 1 MHz. 4. The high thermal expansion porcelain according to claim 3, wherein the Celsian is a hexagonal Celsian having an average aspect ratio of 3 or more. 5. After molding the composition according to claim 1, 800 to
The high thermal expansion porcelain according to claim 3 or 4, which is formed by firing at 1100 ° C. 6. Glass containing 20 to 80% by volume of glass containing 5 to 60% by weight of BaO and 20 to 80% by volume of inorganic filler.
The composition in which the inorganic filler contains a metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or more at 40 ° C. to 400 ° C. of 6 ppm / ° C. or more and cordierite at a ratio of 1 to 80% by weight. 800 ℃ ~ 1 after molding
A method for manufacturing a high thermal expansion ceramics, which comprises firing at a temperature of 100 ° C. 7. After the composition is molded, it is temporarily held at a temperature lower than the optimum firing temperature within a temperature range of 750 to 900 ° C., and then fired at an optimum firing temperature of 800 ° C. to 1100 ° C. The method for manufacturing a high thermal expansion porcelain according to claim 6, which is characterized in that. 8. A multilayer wiring board in which a metallized wiring layer is provided on the surface and / or inside of an insulating substrate in which ceramic insulating layers are laminated in multiple layers, wherein at least one of the ceramic insulating layers is formed. A multilayer wiring board formed by the low dielectric constant layer made of the high thermal expansion ceramic according to claim 5. 9. A linear thermal expansion coefficient at 40 to 400 ° C. of at least one of the ceramic insulating layers is 8 to 1.
9. The multilayer wiring board according to claim 8, comprising a high dielectric constant layer having a relative dielectric constant of 10 or more at 5 ppm / ° C. and 1 MHz. 10. The high dielectric constant layer comprises glass containing BaO and a metal oxide having a linear thermal expansion coefficient of 8 ppm / ° C. or higher at 40 to 400 ° C. as a crystal phase and a relative dielectric constant of 40 or higher at 1 MHz. The multilayer wiring board according to claim 9, comprising: 11. The high dielectric constant layer is disposed between a pair of electrode layers, and a predetermined capacitance is extracted by the pair of electrodes.
0 multilayer wiring board. 12. The low dielectric constant layer and the high dielectric constant layer
The difference in linear thermal expansion coefficient at 0 to 400 ° C is 0.5 ppm /
The temperature is not higher than 0 ° C.
The multilayer wiring board according to any one of 1. 13. A semiconductor device is mounted on the front surface of the insulating substrate, and a connection terminal for connecting to an external circuit is provided on the rear surface of the insulating substrate. Or a multilayer wiring board as described above. 14. An external circuit board having a wiring conductor deposited on the surface of an insulator containing at least an organic resin.
3. A multilayer wiring board mounting structure, wherein the multilayer wiring board No. 3 is mounted, and the connection terminal of the multilayer wiring board and the wiring conductor are brazed to each other. 15. The mounting structure for a multilayer wiring board according to claim 14, wherein the connection terminals are ball-shaped terminals.