JP2002290039A - Method of manufacturing ceramic multilayer board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceramic multilayer board manufacturing method which is capable of easily reducing a change or a variation in the size of a ceramic multilayer board after baking and keeping it high in characteristics and reliability. SOLUTION: This manufacturing method comprises a first process of forming a first slip which contains a first insulating inorganic material and photo-curing resin, and a second slip which contains a second insulating inorganic material whose burning shrinkage starting temperature is higher than that of the first insulating inorganic material by 20 deg.C or above and photo-curing resin; a second process of applying the second slip on a support board 9 and forming it into a second insulating layer molded body 10a by drying; a third process of curing the second insulating layer molded body 10a by light exposure; and a fourth process of applying the first slip on the second insulating layer molded body 10a, forming it into a first insulating layer molded body 10b by drying, and curing the first insulating layer molded body 10b by light exposure. Furthermore, the second to fourth process are repeatedly carried out to form first insulating layer molded bodies 10b to 10g and second insulating layer molded bodies 10a to 10h, and an additional process of separating the laminated molded body from the support board 9 and burning the laminated molded body is included.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic multilayer substrate, and more particularly to a method for manufacturing a ceramic multilayer substrate to be mounted as a component for high frequency use in communication equipment and electronic equipment.

[0002]

2. Description of the Related Art As a method of manufacturing a ceramic multilayer substrate, a green sheet lamination method has conventionally been the mainstream. This is a method of obtaining a substrate by batch-baking a laminated molded body produced by laminating and pressing a plurality of ceramic green sheets on which a pattern serving as an internal wiring and a conductive member serving as a via-hole conductor are formed.

Here, as the conductive material, a silver-based or copper-based conductive material having a lower conductor resistance than that of tungsten or molybdenum and having good high-frequency characteristics is used, and the substrate material can be co-fired with these conductive materials. A low-temperature fired glass-ceramic material was used.

In this manufacturing method, a through-hole for forming a via-hole conductor is formed by mechanical punching with an NC punch or a die. However, in the case of a mold, the number of steps can be reduced by collective formation, but there is a problem of manufacturing cost such as a high mold cost, and a problem of handleability particularly when a thin sheet is punched. Also,
Since the green sheet expands and contracts during handling, there is a problem that the positional accuracy between layers during lamination is not good due to the influence of the deformation.

As a solution to the problem caused by the green sheet laminating method, a ceramic slip containing a photocurable resin is conventionally applied on a supporting substrate by a doctor blade method or the like, and a selective insulating film is applied to the applied insulating film. After the exposure process, a developing process is performed to form a through-hole for forming a via-hole conductor, a process of filling the through-hole with a conductive paste and forming a conductive film for internal wiring on the insulating film. There is known a method of manufacturing a ceramic multilayer substrate using a so-called build-up multilayer method in which a required number of laminations is repeated, and finally, a conductive film to be a surface wiring is formed, and the obtained multilayer molded body is fired at a time to obtain a substrate. .

In such a manufacturing method, for example, a ceramic slip composed of a ceramic powder, an organic binder containing a photocurable resin and a solvent is applied and dried to form an insulating layer molded body on a support substrate. The molded body is exposed and developed to form a through-hole for a via hole, and such a through-hole is filled with a general conductive paste by a screen printing method or the like, heated to disperse the solvent, and dried. A ceramic multilayer substrate is formed by forming a dry conductor, then screen-printing a conductive paste as necessary to form a wiring pattern, and firing the laminated molded body obtained by repeatedly performing the above-described steps. Can be obtained.

According to such a method of manufacturing a ceramic multilayer substrate, a large number of through holes for via holes can be formed at once and inexpensively, so that the manufacturing cost is greatly reduced, and a certain alignment formed on the support substrate is achieved. Since a lamination method using a photolithography process including a build-up multilayer method based on a standard is adopted, the positional accuracy during lamination is extremely high, which is advantageous for high-density mounting. Further, even if a large-diameter hole is formed in a sheet having a small thickness per layer, there is no problem in handling properties, and the problem in the green sheet lamination method can be solved.

[0008]

However, even when a laminate having a high lamination position accuracy is manufactured by the build-up multilayer method, shrinkage accompanying sintering occurs at the time of firing the laminated molded body. In particular, when a photocurable resin is used, there is a problem that the resin component in the slip increases and shrinkage accompanying sintering increases.

The shrinkage due to this sintering is caused by
Since it differs depending on the Y direction or the material lot, the pattern size of the fired body varies. For this reason, there is a problem that it is necessary to perform a design in consideration of the variation when mounting the components on the substrate surface, and there is a problem that a component mounting shift actually occurs, which has caused a restriction in high-density mounting.

As a means for solving such a problem, a material which does not sinter at the sintering temperature of the insulating material is arranged on both surfaces or one surface of the laminated molded body, and the laminated molded body is restrained in a plane direction, so that the laminated molded body during firing can be reduced. A method has been proposed in which shrinkage of the insulating layer laminate in the X and Y directions is suppressed, and after firing, the unsintered material is removed by a method such as polishing. This reduces dimensional changes and variations in the X and Y directions due to firing shrinkage, but it is difficult to completely remove the unsintered material in a short period of time. If unremoved powder remains, the characteristics and reliability of the substrate are reduced. There was a loss.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a ceramic multilayer substrate which can easily reduce dimensional changes and variations after firing and can maintain high characteristics and reliability of the substrate.

[0012]

According to a method of manufacturing a ceramic multilayer substrate of the present invention, a plurality of insulating layers are laminated, and at least one of the plurality of insulating layers starts firing shrinkage with another first insulating layer. A method for producing a ceramic multilayer substrate which is a second insulating layer having a different temperature, comprising the following steps (a) to (f): (A) a first slip containing at least a first insulating inorganic material and a photocurable resin, and a second insulating inorganic material and a light having a firing shrinkage starting temperature different from the first insulating inorganic material by 20 ° C. or more; (B) a step of applying the first or second slip on a support substrate and drying to form a first or second insulating layer molded body (c) A) exposing and curing the first or second insulating layer molded body; and (d) placing the first or second slip on the first or second insulating layer molded body obtained in the step (c). The steps of applying and drying to form a first or second insulating layer molded body, exposing and curing the first or second insulating layer molded body are repeated, and the first insulating layer molded body and the second Step of producing a laminated molded body of the insulating layer molded body (e) the lamination (F) Step of Firing the Laminated Molded Article In the method for producing a ceramic multilayer substrate of the present invention, when the insulating layer molded body having a low firing shrinkage starting temperature starts shrinking, ,
Since the other insulating layer molded body having a high firing shrinkage start temperature prevents shrinkage in the XY directions, the insulating layer molded body having a low firing shrinkage starting temperature hardly shrinks. Next, when the insulating layer molded body having a high firing shrinkage start temperature starts shrinking, since the insulating layer molded body having a low firing shrinkage starting temperature that has already almost finished firing shrinkage prevents shrinkage in the XY directions, The insulating layer molded body having a high shrinkage start temperature hardly shrinks by firing. As a result, firing shrinkage in the XY directions of the entire substrate can be suppressed.

In the method of manufacturing a ceramic multi-layer substrate according to the present invention, the firing shrinkage in the XY directions can be effectively suppressed by setting the firing shrinkage initiation temperature difference to 20 ° C. or more, and the first insulating layer and the first insulating layer can be prevented from being shrunk. (2) Strain at the interface with the insulating layer can be suppressed, and warpage of the substrate, interface peeling, and the like can be suppressed. In particular, the firing shrinkage initiation temperature difference is desirably 50 ° C. or more from the viewpoint of suppressing XY restraint and substrate warpage.

Further, at the firing shrinkage start temperature of the first or second insulating layer molded body having the higher firing shrinkage starting temperature, the second or first insulating layer molded body having the lower firing shrinkage starting temperature is reduced in total volume shrinkage. It is characterized by contraction of 90% or more of the ratio. This makes it possible to reduce the firing shrinkage in the XY directions to 10% or less. In particular, the firing shrinkage rate in the XY directions is 0 to
In order to make the range of 3%, it is desirable that the insulating layer having the lower firing shrinkage start temperature has been shrunk by 97% or more of the total volume shrinkage rate.

Further, in the method for manufacturing a ceramic multilayer substrate according to the present invention, a thickness of 25 μm between the first insulating layer molded body and the second insulating layer molded body in the laminated molded body obtained in the step (d). It is characterized in that the above-mentioned internal conductor pattern is formed.

The reason for this is that by increasing the thickness of the conductor, the conductor resistance of the internal conductor can be reduced, which is advantageous for lowering the resistance of the bias line which affects the characteristics of the power amplifier substrate and the like. is there. However, in the case of the conventional green sheet lamination method, when the film thickness of the conductor formed between the green sheets as the insulating layers is increased,
Due to the influence of the step, the adhesion between the sheets deteriorates, and particularly when an internal conductor pattern is formed between the first insulating layer molded body and the second insulating layer molded body, the first insulating layer molded body and the Due to the difference in firing shrinkage of the two-insulated-layer molded body, the problem of delamination occurs remarkably. Specifically, the conductor film thickness is 25 μm
Above, the tendency becomes clear. In the case of a laminate formed by repeatedly applying and drying a slip material as in the present invention, such a problem does not occur even if the conductor film thickness exceeds 25 μm.

In the method of manufacturing a ceramic multilayer substrate according to the present invention, in the step (d), a predetermined portion of the first or second insulating layer molded body is exposed and developed to form a through hole. It is desirable to include a step of filling the inside with a conductive paste.

Further, in the method for manufacturing a ceramic multilayer substrate of the present invention, it is desirable that the firing shrinkage starting temperature of the first or second insulating layer molded body which shrinks first is 600 ° C. or more. In the case of a normal binder resin, since it is completely decomposed up to 400 to 500 ° C., there is no problem even if firing shrinkage starts at 600 ° C. or less. However, the photocurable resin generally has poorer degradability as its properties are better, and the binder removal temperature is as high as 500 ° C. or more to completely decompose. However, in the present invention, the first and second insulating layers are not used. Since the firing shrinkage start temperature of the molded body is 600 ° C. or higher, firing shrinkage starts after the resin is sufficiently decomposed, and the occurrence of delamination or substrate cracking due to insufficient binder removal can be suppressed.

In the present invention, it is preferable that the lowermost layer and the uppermost layer of the laminated molded article in the laminated molded article are of the same type. In this way, by arranging the insulating layer molded bodies having the same firing shrinkage starting temperature vertically symmetrically, the warpage of the substrate can be effectively suppressed.

[0020]

FIG. 1 is a perspective view of a ceramic multilayer substrate obtained by the method of the present invention.
Denotes an insulating base, and terminals such as an input / output terminal, a power supply terminal, and a ground terminal are shown as end face electrodes 2. The end face electrodes 2 are formed on four sides of the insulating substrate 1 so as to be exposed at a total of ten places.

A surface electrode (wiring) 3 is formed on the upper surface of the insulating base 1, a chip component 5 such as a resistor or a capacitor is connected to the surface electrode 3, and a semiconductor element (IC) 6 Connected to the wire.

FIG. 2 is a cross-sectional view of the above-mentioned multilayer substrate. The insulating layers 1a to 1h are made of a ceramic or glass-ceramic material and have a thickness of 40 to 100.
μm. The second insulating inorganic material forming the second insulating layers 1a and 1h and the first insulating inorganic material forming the first insulating layers 1b to 1g have different firing shrinkage start temperatures and different relative dielectric constants. That is, the second insulating layers 1a and 1h are formed on the uppermost surface and the lowermost surface of the multilayer substrate, and are formed symmetrically. On the lower surface of the insulating base 1, a back electrode 4 serving as a ground conductor is formed.

An internal wiring 7 is formed between the plurality of insulating layers 1a to 1h.
It is made of a silver-based or copper-based metal material, for example, a silver-based conductor. The internal wiring 7 between the insulating layers 1a to 1h is
They are connected by via-hole conductors 8 penetrating through a to ah. The via hole conductor 8 is also made of a gold-based, silver-based, or copper-based metal material, for example, a silver-based conductor, like the internal wiring 7.

On the surface of the insulating substrate 1, a surface electrode 3 connected to the via-hole conductor 8 of the insulating layer 1h is formed.
The surface electrode 3 is plated as necessary, and various chip components 5 are joined by soldering.

Such a multilayer substrate is manufactured by the manufacturing steps shown in FIG. First, the second insulating layers 1a, 1h,
First and second slips for the first and second insulating layer molded bodies to be the first insulating layers 1b to 1g are produced. The first and second slips are obtained by combining a first and second insulating inorganic material, a photocurable monomer such as polyoxyethylated trimethylolpropane triacrylate, an organic binder such as alkyl methacrylate, and a plasticizer. It is prepared by mixing with a solvent such as ethyl carbitol acetate and kneading with a ball mill.

The first insulating inorganic material forming the first insulating layers 1b to 1g is, for example, at least Mg as a metal element.
A composite oxide containing Ti and Ca, wherein the composition formula of the metal element oxide is (1-x) MgTiO ₃ -xC
aTiO ₃ (where x represents a weight ratio, 0 ≦ x ≦
With respect to 100 parts by weight of the main component represented by 0.2), the B-containing compound is ₃ to 20 parts by weight in terms of B ₂ O ₃ , the alkali metal-containing compound is 1 to 10 parts by weight in terms of an alkali metal carbonate, Si is 0.01 to 5 parts by weight in terms of SiO ₂ , and alkaline earth metal is 0.1 to 5 parts in terms of alkaline earth metal oxide.
Those containing parts by weight are used. Such first
The insulating inorganic material has a firing temperature of about 900 ° C., a firing shrink start temperature of about 800 ° C., and a relative dielectric constant of 18 to 20.
It is about.

The second insulating inorganic material constituting the second insulating layers 1a and 1h is, for example, alumina, silica, MgTi
0 to 30 parts by weight of at least one selected from O ₃ and MgTiO ₃ —CaTiO ₃ , and SiO ₂ , CaO, MgO, Ti
It is composed of 70 to 100 parts by weight of crystallized glass containing O _2, and the difference between the firing shrinkage initiation temperature and the first insulating inorganic material constituting the first insulating layers 1 b to 1 g is 20 ° C. or more. The firing shrinkage start temperature of the insulating inorganic material is higher than that of the second insulating inorganic material, and the relative dielectric constant is about 6 to 10.

The difference between the firing shrinkage starting temperatures of the first insulating inorganic material and the second insulating inorganic material is set to 20 ° C. or more because if the firing shrinking starting temperature difference is smaller than 20 ° C., the mutual shrinkage of the materials is reduced. This is because they cannot be hindered, and the dimensional change in the XY directions increases. The firing shrinkage initiation temperature difference is particularly 5
0 ° C. or higher is desirable. In order to suppress delamination or the like due to a difference in shrinkage, the difference in firing shrinkage start temperature is preferably 150 ° C. or less, particularly preferably 100 ° C. or less.

In the above embodiment, a solvent-based slip material is prepared. However, a photocurable monomer having a hydrophilic functional group added thereto, for example, a polyfunctional methacrylate monomer,
An aqueous slip material kneaded with ion-exchanged water using an organic binder, for example, a carboxyl-modified alkyl methacrylate, may be used. Examples of the insulating inorganic material include glass materials such as SiO ₂ , Al ₂ O ₃ , ZnO, M
A powder composed of 70% by weight of crystallized glass powder mainly containing gO and B ₂ O ₃ and 30% by weight of alumina powder as a ceramic material is also used. The glass-ceramic raw material powder and the ceramic raw material powder are not particularly limited.

Further, a conductive paste to be the via-hole conductor 8, the internal wiring 7, the front electrode 3, and the back electrode 4 is prepared. The conductive paste is a metal material having a low melting point and low resistance, for example, silver powder and a borosilicate low melting point glass, for example, B ₂ O ₃ —SiO ₂ —BaO glass, CaO—B ₂ O ₃
—SiO ₂ glass, CaO—Al ₂ O ₃ —B ₂ O ₃ —SiO ₂
Glass and an organic binder such as ethylcellulose are mixed with an organic solvent such as 2,2,4-trimethyl-1,3.
Mixed with pentadiol monoisobutyrate and homogenously kneaded with three rollers.

First, as shown in FIG. 3 (a), the multi-layer substrate of the present invention comprises a second slip containing the above-mentioned low dielectric constant second insulating inorganic material on a supporting substrate 9 by a doctor blade method. To form an insulating layer 1a by applying and drying
An insulating layer molded body 10a is formed. Note that a glass plate, a PET film, or the like is used as the support substrate 9 and is removed before the firing step.

Next, the second insulating layer molded body 10a is exposed to light to form through holes 12a. Through hole 12a
Is formed by an exposure process, a development process, and a washing / drying process.

In the exposure treatment, a photo target is placed on the second insulating layer molded body 10a so that the area where the through hole 12a is formed is shielded from light, and for example, an ultra-high pressure mercury lamp (10 mW / cm ² ) Exposure is performed using as a light source. Thereby, the second region of the region where the through hole 12a is formed is formed.
The photopolymerization reaction of the photocurable monomer does not occur in the insulating layer molded body 10a, and the photopolymerization reaction occurs in the second insulating layer molded body 10a other than the region where the through hole 12a is formed. Here, the part where the photopolymerization reaction has occurred is called an insolubilized part, and the part where the photopolymerization reaction does not occur is called a solubilized part.

In the developing treatment, the solubilized portion of the second insulating layer molded body 10a is removed with a developing solution.
Spray development is performed using a triethanolamine aqueous solution as a developer. By this developing process, as shown in FIG. 3B, a through hole 12a can be formed in the second insulating layer molded body 10a. Then, the second insulating layer molded body 10
Unnecessary residue generated by development a is completely removed by washing and drying processes.

The developing device used for this is a paddle processing tank,
It consists of three processing tanks, a spray processing tank and a pure water cleaning processing tank. The work is transported through each tank in order by a conveyor, and an air shower is provided at the end of each tank, so that the developer and pure water are sufficiently removed. It has become.

Next, a conductive paste is filled into the through holes 12a. Specifically, as shown in FIG. 3C, the inside of the through-hole 12a formed in the above-described process is filled by printing using a screen capable of printing only a portion corresponding to the through-hole 12a, and thereafter, Dry under predetermined conditions, for example, at 80 ° C. for 10 minutes.

Next, an internal wiring pattern 15 to be the internal wiring 7 is formed. The internal wiring pattern 15 is formed by printing the above-mentioned conductive paste on the second insulating layer molded body 10a by using a screen printing method, and then drying the conductive paste at a predetermined condition, for example, at 80 ° C. for 10 minutes. You.

Next, as shown in FIG. 3D, the first slip material containing the above-mentioned first insulating material having a high dielectric constant is applied and dried by a doctor blade method to form a first insulating layer 1b. Is formed to form a first insulating layer molded body 10b.

By repeating the above steps, FIG.
As shown in (e), the insulating layer molded bodies 10a to 10h are laminated. Here, the first insulating layer molded body 10b to 10g is a first slip material containing a high dielectric constant first insulating inorganic material, and the second insulating layer molded body 10h is a low dielectric constant second insulating inorganic material. Is formed using a second slip material containing

After forming the second insulating layer molded body 10h, a surface wiring pattern to be the surface electrode 3 is formed. The surface wiring pattern is formed by printing the above-mentioned conductive paste on the second insulating layer molded body 10h by using a screen printing method, and then drying it at a predetermined condition, for example, at 80 ° C. for 10 minutes to form a laminated molded body. Is formed.

Here, in the present invention, at the firing shrinkage starting temperature of the first insulating layer molded bodies 10b to 10g having a high firing shrinkage starting temperature, the total volume of the second insulating layer molded bodies 10a and 10h having a low firing shrinking starting temperature is reduced. It is desirable that the shrinkage is at least 90% of the shrinkage. Thereby, the firing shrinkage rate in the XY directions can be reduced to 10% or less. In particular, in order to set the firing shrinkage in the XY directions to be in the range of 0 to 3%, the second insulating layer molded bodies 10a and 10h having low firing shrinkage starting temperatures are shrunk by 97% or more of the total volume shrinkage. Is desirable.

It is desirable that the firing shrinkage onset temperature of the second insulating layer molded bodies 10a and 10h, which shrink first, is 600 ° C. or higher. After the photocurable resin is reliably decomposed, firing shrinkage starts, and the occurrence of delamination or substrate cracking due to insufficient binder removal can be suppressed.
First insulating layer molded body 10b to 10g, second insulating layer molded body 1
It is desirable that the firing shrinkage starting temperatures of 0a and 10h be 700 ° C or higher.

The difference between the thermal expansion coefficients of the first and second insulating layer molded bodies 10b to 10g and 10a and 10h is 2 × 10
It is desirable to be ^-6 / ° C or lower. First insulating layer molded body 1
By setting the difference in thermal expansion coefficient between 0b to 10g and the second insulating layer molded bodies 10a and 10h to 2 × 10 ⁻⁶ / ° C. or less, the thermal shrinkage behavior of the insulating inorganic material at the time of cooling from the peak firing temperature is substantially reduced. Since they can be matched and a shrinkage mismatch can be eliminated, the occurrence of cracks or delamination can be prevented.

Thereafter, the laminated molded body is removed from the support substrate 9 and the shape is adjusted by pressing if necessary. Thus, a multilayer molded body of a multilayer substrate as shown in FIG.

The back electrode 4 may be formed by printing the above-mentioned conductive paste on the support substrate 9 by using a screen printing method before the formation of the lowermost second insulating layer molded body 10a. After the support substrate 9 is removed, the above-described conductive paste may be formed by printing using a screen printing method.

Next, a dividing blade is formed by pressing a sharp blade from both sides of the laminated molded body to a position where the circuit block is divided.

Thereafter, the binder is removed at 300 to 500 ° C., and the mixture is calcined at 800 to 1100 ° C. In the binder removing step, the organic binder and the photocurable monomer contained in the binder are eliminated. Sinter.

Thereafter, as a surface treatment, printing and baking of a thick-film resistive film and a thick-film protective film, plating, and bonding of the chip component 5 and the semiconductor element 6 are performed.

According to the above manufacturing method, different second insulating layer molded bodies 10a and 10h and first insulating layer molded bodies 10b to 10b
The XY shrinkage rate of the entire substrate can be suppressed from the difference in firing shrinkage starting temperature from g. In the process of laminating the insulating layer molded body, the internal wiring pattern 15 is formed on an arbitrary layer of the insulating layer molded body 10a to 10h, and the film thickness is 25 μm.
Even in the case described above, since a slip containing an insulating material is applied to the upper surface, a gap is formed between the internal wiring pattern 15 and the insulating layer molded bodies 10a to 10h formed on the upper surface. Therefore, the adhesion becomes sufficient and the occurrence of delamination after sintering can be prevented.

[0050]

Against EXAMPLES _{(1-x) MgTiO 3 ·} xCaTiO 3, B 2 O 3 powder, an alkali metal carbonate powder (Li ₂ C
O ₃ , Na ₂ CO ₃ , K ₂ CO ₃ ), SiO ₂ powder, MnO ₂
Powder, and further alkaline earth oxide powder (MgO, Ca
O, SrO, BaO), a first insulating inorganic material to which a predetermined amount is added, a crystalline glass comprising 52% by weight of SiO ₂ , 25% by weight of CaO, 18% by weight of MgO, and 5% by weight of Al ₂ O ₃ ; To a second insulating inorganic material obtained by adding a ceramic powder composed of SiO ₂ , a polyoxyethylated trimethylolpropane triacrylate as a photocurable resin, an alkyl methacrylate as an organic binder, and ethyl as an organic solvent. Carbitol acetate and a plasticizer were mixed and kneaded with a ball mill to prepare first and second slurries.

The firing shrinkage starting temperature was changed by changing the value of x and the amount of additive in the first insulating inorganic material, and changing the ratio of crystalline glass to ceramic powder in the second insulating inorganic material. .

The second slurry is applied to a supporting substrate, exposed and developed to form a second insulating layer molded body having a through hole formed therein, and Ag is contained in the through hole of the second insulating layer molded body. The conductive paste to be applied was filled, and the conductive paste was applied to the surface of the second insulating layer molded body to form an internal electrode pattern.

The first insulating layer molded body was coated with a first slurry, exposed and developed to produce a first insulating layer molded body having a through-hole formed therein. After the above was repeated, the second slurry was applied onto the uppermost first insulating layer molded body, and exposed and developed to produce a laminated molded body shown in FIG. 3 (f).

Thereafter, a binder removal treatment was performed in the air, followed by firing at 910 ° C., thereby producing a ceramic multilayer substrate as shown in FIG.

The shrinkage in the X and Y directions of the substrate was measured by measuring the length between predetermined points on the laminated molded body and the fired circuit board. In addition, the substrate is polished for cracks and delaminations,
It was evaluated by observation with a metallographic microscope.

Further, a wax is added to the first insulating inorganic material and the second insulating inorganic material and pressed at 10 ton / cm ² to form a green compact, which is then subjected to thermomechanical analysis (TMA).
The firing shrinkage starting temperature and the coefficient of thermal expansion of the material were evaluated. The resistance value of the inner layer pattern was measured using a milliohm meter, and the resistance value per unit length (mΩ / mm) was calculated. Table 1 shows the results.

[0057]

[Table 1]

From Table 1, it can be seen that the ceramic multilayer substrate of the present invention has a small shrinkage ratio of 0.5 to 7.0, does not cause cracks or delamination during firing, and has a wiring resistance satisfying the standard. It can be seen that it can be obtained. Further, as a comparative example, when a sample having a shrinkage initiation temperature difference of less than 20 ° C. was evaluated, delamination occurred.

[0059]

According to the method for manufacturing a ceramic multilayer substrate of the present invention, when an insulating layer molded body having a low firing shrinkage start temperature starts shrinking, the other insulating layer molded body having a high firing shrinkage starting temperature is used. Because shrinkage in the XY directions is prevented,
The formed insulating layer having a low firing shrinkage temperature hardly shrinks. Next, when the insulating layer molded body having a high firing shrinkage start temperature starts shrinking, the shrinkage in the XY directions is prevented by the low insulating layer molded body having a firing shrinkage start temperature that has almost already finished firing shrinkage. The insulating layer molded body having a high firing shrinkage start temperature hardly shrinks. As a result, firing shrinkage in the XY directions of the entire substrate can be suppressed.

In the case where a laminated molded article is formed from an insulating layer molded article formed by applying a slip containing a photocurable resin, even if an internal wiring pattern is formed on the insulating layer molded article, Slip containing a sintering material is applied to the upper surface, so that while maintaining excellent positional accuracy, dimensional accuracy stability during firing can be obtained, and the internal wiring pattern and the formation of the insulating layer formed on the upper surface No gap is formed between the body and the body, the adhesion is sufficient, the occurrence of delamination after sintering can be prevented, and the reliability of the product can be improved. Therefore, high dimensional accuracy,
In addition, a ceramic multilayer substrate having a high-density wiring pattern can be obtained.

Further, by simultaneously forming insulating materials having different relative dielectric constants on one substrate, it is possible to reduce the size of circuit elements incorporated in the substrate.

[Brief description of the drawings]

FIG. 1 is a perspective view of a ceramic multilayer substrate obtained by a manufacturing method of the present invention.

FIG. 2 is a sectional view of a ceramic multilayer substrate.

FIG. 3 is a process chart for explaining a method for producing a ceramic multilayer substrate of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a, 1h ... Low dielectric constant second insulating layer 1b-1g ... High dielectric constant first insulating layer 9 ... Support substrate 10a, 10h ... Low dielectric constant Second insulating layer molded body 10b to 10g: High dielectric constant first insulating layer molded body 12a: Through hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/40 H05K 3/40 K (72) Inventor Seiichiro Hirahara 1-4-4 Yamashita-cho, Kokubu-shi, Kagoshima KYOCERA (72) Inventor Tatsuharu Furuse 1-4-4 Yamashita-cho, Kokubu-shi, Kagoshima F-term in Kyocera Research Institute (reference) 4G031 AA01 AA03 AA04 AA11 AA19 AA29 AA30 AA39 BA12 CA03 CA08 5E317 AA24 BB04 BB11 CC22 CC25 CD21 CD25 CD32 GG14 5E346 AA12 AA15 AA24 AA38 AA43 BB01 BB15 CC18 CC31 DD02 DD34 EE24 EE27 EE29 FF18 GG03 GG04 GG06 GG09 HH07 HH11 HH21

Claims (6)

[Claims] A method for manufacturing a ceramic multilayer substrate comprising a plurality of insulating layers laminated, wherein at least one of the plurality of insulating layers is a second insulating layer having a different firing start temperature from another first insulating layer. A method for producing a ceramic multilayer substrate, comprising the following steps (a) to (f). (A) a first slip containing at least a first insulating inorganic material and a photocurable resin, and a second insulating inorganic material and a light having a firing shrinkage starting temperature different from the first insulating inorganic material by 20 ° C. or more; (B) a step of applying the first or second slip on a support substrate and drying to form a first or second insulating layer molded body (c) A) exposing and curing the first or second insulating layer molded body; and (d) placing the first or second slip on the first or second insulating layer molded body obtained in the step (c). The steps of applying and drying to form a first or second insulating layer molded body, exposing and curing the first or second insulating layer molded body are repeated, and the first insulating layer molded body and the second Step of producing a laminated molded body of the insulating layer molded body (e) the lamination (F) a step of baking the laminated molded body 2. A firing shrinkage start temperature of a first or second insulating layer molded body having a higher firing shrinkage start temperature, wherein the second or first insulating layer molded body having a lower firing shrinkage start temperature has a total volume shrinkage. 2. The method for producing a ceramic multilayer substrate according to claim 1, wherein the contraction is at least 90% of the ratio. 3. An internal conductor pattern having a thickness of 25 μm or more is formed between the first insulating layer molded body and the second insulating layer molded body in the laminated molded body obtained in the step (d). The method for producing a ceramic multilayer substrate according to claim 1 or 2, wherein: 4. A step of exposing and developing a predetermined portion of the first or second insulating layer molded body to form a through hole during the step (d), and filling the through hole with a conductive paste. The method for producing a ceramic multilayer substrate according to any one of claims 1 to 3, wherein: 5. The ceramic multilayer substrate according to claim 1, wherein the firing shrinkage starting temperature of the first or second insulating layer molded body which shrinks first is 600 ° C. or more. Recipe. 6. The ceramic multilayer substrate according to claim 1, wherein the lowermost and uppermost insulating layer molded bodies in the laminated molded body are the same kind of insulating layer molded body. Recipe.