JPH10107439A - Manufacturing method of laminated ceramic board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a laminated ceramic board by which a high precision deep cavity for receiving an electronic component can be easily formed. SOLUTION: A method comprises the steps of: fabricating ceramic layer molding members 11a-11e to become ceramic layers by spreading a ceramic slip material containing a monomer capable of at least photosetting; forming an opening 40, at the location where a cavity is to be formed, by selectively subjecting the ceramic layer molding members 11a-11e to exposing or developing processes; filling a region paste containing a photosetting or thermosetting monomer into the opening 40 and setting the resin paste by exposing it to light or heating it; and heating the laminated mold 11 formed by repeating these steps to burn out the resin 41 filled in the opening 40.

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 multilayer ceramic substrate having a cavity for storing electronic components.

[0002]

2. Description of the Related Art Conventionally, a multilayer circuit board is composed of a multilayer ceramic substrate and electronic components mounted on the surface of the multilayer ceramic substrate. And via-hole conductors for connecting the two.

However, electronic components mounted on a multilayer ceramic substrate include an IC chip, a transistor, a filter element, a chip capacitor, and the like. In order to reduce the height required for a multilayer circuit substrate, an IC chip or a transistor is required. Mounting of large chip components such as was an obstacle.

Therefore, as a structure for reducing the height of the multilayer ceramic substrate, a solution is provided by forming a cavity in an electronic component storage portion of the multilayer ceramic substrate, and storing and arranging a high electronic component there. I was planning.

One of the methods for manufacturing the multilayer ceramic substrate having the cavity structure is a green sheet multilayer method. This involves laminating and pressing a plurality of ceramic green sheets having a pattern serving as an internal wiring or a conductive member serving as a via-hole conductor, and an opening for forming a cavity, to produce a laminated molded body, which is then fired. This is a method for obtaining a multilayer ceramic substrate. In this method, the formation of the through-hole for forming the via-hole conductor and the opening for forming the cavity is performed by punching with an NC punch or a metal mold.

[0006]

However, in the case of the green sheet multi-layer system, there is a problem of alignment at the time of lamination, the inner wall surface of the cavity may not be straight, but may have a stepped structure, and one sheet may be used. In addition, when a large hole for accommodating electronic components is formed as an opening for forming a cavity, especially in the case of a thin sheet, there is a problem that handling properties are deteriorated.

As a method of manufacturing a multilayer ceramic substrate for solving the above-mentioned problem of the green sheet multilayer method, the present inventors firstly prepared a ceramic slip material containing a photocurable monomer on a supporting substrate by a doctor blade method. After applying a selective exposure process to the applied ceramic molded body, a developing process is performed to simultaneously form a through-hole for forming a via-hole conductor and an opening for forming a cavity. A manufacturing method was proposed in which a required number of layers were repeatedly filled with a conductive paste and a pattern for internal wiring was formed on the ceramic layer molded body to produce a laminated molded body, and the laminated molded body was fired at a time to obtain a substrate. Kaihei 07-1
No. 54073). According to this method, since a lamination method using a photo process is employed, positional accuracy at the time of lamination is improved, and even if a large-diameter hole is formed in a sheet having a small thickness, there is a problem in handling. However, the problem in the green sheet multilayer method can be solved.

However, in the case of forming an opening for forming a cavity by this exposure / development process, it becomes more difficult to form an opening with higher precision as the opening becomes deeper.

That is, since the components housed in the cavity usually have a height of about 200 μm to 500 μm, in order to further reduce the height of the laminated circuit board, the cavity having a depth corresponding to the component height is required. Is required.

However, the thickness of a ceramic layer molded body per one layer in which a through hole for a via-hole conductor can be formed by one exposure / development is at most 200 μm. Exposing and developing a ceramic layer molded body with a thickness greater than that may result in excessive development in order to prevent development residue, and the shape of the through-hole for forming via-hole conductors is filled with conductor paste. In addition to the case where the shape is not suitable for the ceramic layer, in the worst case, the ceramic layer molded body may be melted.

Further, it is difficult to form a small through-hole having a diameter of 100 to 120 μm by exposure and development in a thick ceramic layer molded body having a thickness exceeding 200 μm due to the characteristics of the photosensitive material. Will not be obtained. Usually, a through hole having a diameter of 100 to 120 μm is exposed and
The film thickness suitable for forming by development processing is 150 μm or less.

Therefore, for example, in order to accurately form a cavity having a depth of about 500 μm by the present manufacturing method, it is necessary to repeat a process of forming an opening for forming a cavity in a ceramic layer molded body of 150 μm or less. In addition, a manufacturing method is required to prevent development residue from remaining in a portion to be a cavity opening.

However, the above-mentioned Japanese Patent Application Laid-Open No.
In No. 73, since the slurry is further applied onto the cavity opening once formed, the cavity opening is filled with the slurry, and two layers including the cavity opening need to be developed. In this case, there was a problem that the development could not be performed completely and the ceramic component of the slurry remained in the cavity opening.

In the case where an opening for forming a cavity is required on the back side of the substrate, in the above-described method of applying and laminating the ceramic slip material, the opening once formed is filled when the next layer of the ceramic slip material is applied. Because
It was impossible to form an opening of an arbitrary depth on the back surface of the substrate.

[0015] The present invention provides a deep,
For example, it is an object of the present invention to provide a method for manufacturing a multilayer ceramic substrate that can easily and accurately form a cavity forming opening of about 500 μm.

[0016]

A method of manufacturing a multilayer ceramic substrate according to the present invention is a method of manufacturing a multilayer ceramic substrate in which a cavity for accommodating an electronic component is formed on a surface of a substrate formed by laminating a plurality of ceramic layers. The following (a)-
A method for manufacturing a multilayer ceramic substrate, comprising the step (g).

(A) a step of producing a ceramic slip containing at least a photo-curable monomer; (b) a step of forming a ceramic layer compact by thinning and drying the ceramic slip; and (c) forming a ceramic layer compact. Subject the body to exposure and development,
Forming a cavity opening in a part of the ceramic layer molded body and curing the ceramic layer molded body; and (d) providing a light or heat curable monomer to the cavity opening in the ceramic layer molded body. Filling the resin paste containing the resin paste and curing the resin paste by exposure or heating. The surface of the ceramic layer molded body obtained in the steps (e) and (d) and the resin cured in the cavity opening is formed on the surface. Step of applying a ceramic slip and drying to form a ceramic layer molded body (f) With respect to the ceramic layer molded body formed in the step (e), (c), (d), and (e) are sequentially performed. A step of repeatedly producing a laminated molded body in which a plurality of the ceramic layer molded bodies are laminated (g) heating the laminated molded body to form a laminate inside the cavity opening; Step of Forming Electronic Component Storage Cavity by Spraying Resin It is desirable that the resin filled in the cavity opening be decomposed at a temperature of 600 ° C. or less.

Through the steps (a) to (g), holes can be formed penetrating the laminated ceramic substrate in the thickness direction.

[0019]

According to the present invention, a ceramic layer molded body containing a photo-curable monomer is subjected to exposure and development treatments so that a deep opening such as a cavity can be formed in a laminated body with high accuracy regardless of its depth. It can be easily formed in a shape, and in some cases, it is possible to accurately form a hole penetrating the laminate in an arbitrary shape.

In the conventional opening for forming a cavity by exposure and development processing, since the film is not destroyed as the layers are stacked, the developing strength is restricted, and the opening for forming the cavity with high precision is formed. However, in the case of the present invention, since the opening formed by development is once filled with a resin paste having good thermal decomposability and lamination is repeated, the developing strength for forming the opening for forming the cavity of each layer is increased. However, an opening with poor shape accuracy due to insufficient development is not formed.

The filled resin is easily burned off during de-buying or baking, so that it can be easily removed, and a laminated ceramic substrate having an opening or a through hole for forming a cavity with high precision and an arbitrary shape is formed. It becomes possible.

Further, according to the present invention, it is possible to form a cavity opening of any shape and depth on the back surface of the substrate.

[0023]

【Example】

Embodiment 1 Hereinafter, the present invention will be described with reference to the drawings. FIG. 1 shows a laminated ceramic substrate obtained by the production method of the present invention, and FIG. 2 shows a laminated molded body of the laminated ceramic substrate before firing.

The laminated molded body 11 shown in FIG. 2 is composed of ceramic layer molded bodies 11a to 11e, an internal wiring pattern 31, a surface conductive film 51, a via hole conductor connecting the patterns 31 and the like arranged between the respective layers. A conductive member 21, an opening 40 for forming a cavity formed through the ceramic layer molded bodies 11 a to 11 c on the surface of the laminated molded body, and a resin 41 filled in the opening 40.
By firing this integrally, the ceramic layers 1a to 1a
A base 1 including 1e, internal wiring 3, surface wiring 5, via hole conductor 2, and cavity 4 is manufactured. A thick resistor film is formed on the surfaces of the ceramic layers 1a and 1e as necessary, and other electronic components are mounted.

The ceramic layers 1a to 1e are, for example, 850
A ceramic layer or a glass ceramic material that can be fired at a temperature of about
The thickness of each e is 40 to 200 μm. The thickness of each of these ceramic layers 1a to 1e may be arbitrarily formed.
And an internal wiring 3 between each of the plurality of ceramic layers 1a to 1e, a via-hole conductor 2 connecting each wiring 3 between the layers,
And a cavity 4 is formed.

The via-hole conductor 2 is made of the same metal material as that of the internal wiring 3, such as gold, silver, or copper, and is connected to each of the ceramic layers to connect between the internal wirings 3 or to connect the internal wiring 3 to the surface wiring 5. 1a to 1e.

The internal wiring 3 and the surface wiring 5 are made of a gold-based, silver-based, or copper-based metal material, for example, a silver-based conductor.
The thickness of these wirings is about 5 to 15 μm.

The cavity 4 is formed in a concave shape on the surface of the base 1, and is formed by stacking openings 40 passing through the thickness of the ceramic layers 1a, 1b, 1c. On the bottom surface of the cavity 4, a part of the internal wiring 3 arranged between the ceramic layers 1 c and 1 d is exposed as a connection electrode pad 3 ′ with the electronic component 6 housed in the cavity 4. . The planar shape of the cavity 4 is substantially a shape capable of accommodating the electronic component 6, for example, a rectangular shape, a circular shape, or a shape similar to the electronic component 6, and the depth thereof is completely accommodated in the electronic component 6. It is preferable that the electronic component 6
May protrude from the base 1. Cavity 4
, A plurality of electronic components may be arranged.

Next, a method for manufacturing a multilayer ceramic substrate according to the present invention will be described with reference to FIGS.

First, as shown in FIG. 3A, a ceramic layer molded body 11e to be a ceramic layer 1e is formed on a support substrate 7 such as glass or ceramic. The ceramic layer molded body 11e has a film thickness of 40 after drying a slip material obtained by homogeneously kneading a ceramic material, a glass material, a photocurable monomer, an organic binder, and an organic solvent or water.
It is applied so as to have a thickness of about 200 μm, and dried to form.

The above ceramic materials include cristobalite, quartz, corundum (α alumina), mullite,
There are powders of zirconia, cordierite and the like, and the average particle size is preferably 1.0 to 6.0 μm, more preferably 1.5 to 4.0 μm.

These ceramic materials may be used as a mixture of two or more kinds. Particularly when corundum is used, it is advantageous in terms of cost.

Here, the average particle size of the ceramic material is 1.
If the thickness is less than 0 μm, it is difficult to form a slip, and at the time of exposure described later, exposure light is irregularly reflected, so that sufficient exposure cannot be performed. Conversely, if the average particle size exceeds 6.0 μm, it is difficult to obtain a dense ceramic layer.

The glass material is a glass frit containing a plurality of metal oxides. After firing at 850 to 1050 ° C., cordierite, mullite, anorthite, Celsian, spinel, garnite, willemite, dolomite, petalite, and the like are substituted. As long as at least one kind of derivative crystal is precipitated, a ceramic layer with high strength can be obtained. In particular, when a crystallized glass frit that precipitates anorthite or Celsian is used, a ceramic layer having higher strength can be obtained, and when a crystallized glass frit that can precipitate cordierite or mullite is used, thermal expansion after firing is performed. Since the rate is low, it is effective as a circuit board for arranging a silicon chip such as an IC on the circuit board.

The most preferred glass materials in consideration of the strength and coefficient of thermal expansion of the ceramic layer are B ₂ O ₃ and S
It is a glass frit containing iO ₂ , Al ₂ O ₃ , ZnO, and alkaline earth oxide. Such a glass frit
Since the vitrification range is wide and the yield point is around 600 to 800 ° C., when firing at about 850 to 1050 ° C., copper-based, silver-based, and gold used as internal wiring and via-hole conductors used for low-temperature fired multilayer ceramic circuit boards It is suitable for the sintering behavior of conductive materials. The effect of each component is B
₂ O ₃ and SiO ₂ are mainly used as a network former, and Al ₂ O ₃ is mainly used as an intermediate.
ZnO and alkaline earth oxides mainly further act as network modifiers.

Such a glass material can be obtained by mixing the above-mentioned predetermined components in a predetermined ratio, heating and melting, quenching and then pulverizing. The average particle size of the crushed glass frit is 1.0 to 5.0 μm, preferably 1.
5 to 3.5 μm.

Here, if the average particle size is less than 1.0 μm, it is difficult to form a slip, and at the time of exposure to be described later, exposure light is irregularly reflected, so that sufficient exposure cannot be performed. Conversely, if the average particle size exceeds 5.0 μm, the dispersibility is impaired, and more specifically, the particles cannot be uniformly dissolved and dispersed between ceramic powders as insulating materials, and the strength is extremely reduced.

The composition ratio of the above-mentioned ceramic material and glass material is such that the ceramic material is 10 wt% to 50 wt%,
It is preferably 20 wt% to 35 wt%, and the glass material is 90 wt% to 50 wt%, preferably 80 wt% to 6 wt%.
5 wt%.

Here, if the ceramic material is less than 10 wt% and the glass material exceeds 90 wt%, the glass quality of the ceramic layer is excessively increased, which is unsuitable even from the viewpoint of the strength of the ceramic layer. Material is 50w
If the glass material content exceeds t% and the glass material content is less than 50 wt%, the exposure light is irregularly reflected at the time of exposure described later, and sufficient exposure cannot be performed, and the denseness of the fired ceramic layer is also impaired.

In addition to the above-described ceramic material and glass material, the constituent materials of the slip material include a photocurable monomer and an organic binder which are eliminated by sintering, and further include an organic solvent or water. A slip material containing an organic solvent is called a solvent-based slip material, and a slip material containing water is called a water-based slip material.In the solvent-based slip material and the water-based slip material, a photocurable monomer and an organic binder are slightly mixed. different.

Incidentally, the organic solvent or water mainly adjusts the viscosity of the slip and the like, and is completely lost during the binder removal process in the firing step.

The photocurable monomer of the solvent-based slip material must have excellent thermal decomposition properties in order to cope with a low-temperature, short-time sintering step. As a photocurable monomer, a monomer having a secondary or tertiary carbon, which needs to be photopolymerized by exposure after application of a slip material and drying, capable of forming free radicals and chain growth addition polymerization. For example, alkyl acrylates such as butyl acrylate having at least one polymerizable ethylenic group and the corresponding alkyl methacrylates are effective. Further, polyethylene glycol diacrylates such as tetraethylene glycol diacrylate and methacrylates corresponding thereto are also effective. The photocurable monomer is added in such a range that it can be cured by exposure and a portion other than the exposure can be easily removed by development. For example, the amount is 5 to 15 parts by weight or less based on 100 parts by weight of the solid content.

The organic binder of the solvent-based slip material must have good thermal decomposability like the photo-curable monomer. At the same time, the viscosity of the slip is determined, so wettability with solids must be emphasized. According to the study of the present inventors, carboxyl groups such as acrylic acid or methacrylic acid polymers, alcoholic hydroxyl groups Preferred are ethylenically unsaturated compounds with The addition amount is preferably 25 parts by weight or less based on 100 parts by weight of the solid content.

Further, the photocurable monomer and the organic binder of the aqueous slip material must be water-soluble, and a hydrophilic functional group, for example, a carboxyl group is added to the monomer and the organic binder. The amount of addition is 2 to 300, preferably 5 to 100, when expressed in acid value.
If the added amount is small, the solubility in water and the dispersibility of the solid component powder become poor, and if the added amount is large, the thermal decomposability becomes poor. In consideration of the above, it is appropriately added within the above range.

The photocurable monomer and organic binder in any of the slip materials must have good thermal decomposability as described above.
It must be capable of thermal decomposition below ℃. More preferably, the temperature is 500 ° C. or lower. If the thermal decomposition temperature exceeds 600 ° C., it remains in the ceramic layer, is trapped as carbon, changes the color of the substrate to gray, and lowers the insulation resistance of the ceramic layer. In addition, it may become a void and cause delamination.

As a slip material, a sensitizer, a photo-initiating material or the like may be added as required. For example,
Examples of the photoinitiating material include benzophenones and acyloin ester compounds.

As described above, a ceramic material, a glass material, a photocurable monomer, an organic binder, and an organic solvent or water are mixed and kneaded to form a solvent-based slip material or a water-based slip material to be a ceramic layer. You. The method of mixing and kneading may be a conventionally used method, for example, a method using a ball mill. The method of thinning the slip material is, for example, a doctor blade method (knife coat method), a roll coat method, a printing method, and the like, in particular, a doctor blade in which the surface of the ceramic molded body after application is easy to be flattened. Method is suitable.
The viscosity is adjusted to a predetermined value according to the application method.

The drying is carried out using a batch drying oven or an in-line drying oven, and the drying temperature is preferably 100 ° C. or less. Since rapid drying may cause cracks or the like on the surface, it is necessary to avoid rapid heating.

Next, as shown in FIGS. 3B and 3C,
Exposure processing and development processing are performed on the ceramic layer molded body 11e to form through holes 20 for forming via-hole conductors 21 at predetermined positions.

More specifically, in the exposure treatment, a photo target is placed on the ceramic layer molded body 11e so that the area where the through hole 20 is formed is shielded from light, and an ultra-high pressure mercury lamp (10 mW / cm ^{2) is used.} ) Is used as a light source for exposure. Since the photocurable monomer contained in the slip material is of a negative type, the photopolymerizable reaction of the photocurable monomer does not occur in the ceramic layer molded body 11e in the region where the through-hole 20 is formed. In the ceramic layer molded body 11e other than the region where the hole 20 is formed, a photopolymerization reaction occurs. Here, the site where the photopolymerization reaction has occurred is called an insolubilized portion x, and the site where the photopolymerization reaction does not occur is called a solubilized portion y. The ceramic layer molded body 11e having a thickness of about 100 μm was measured with an ultrahigh pressure mercury lamp (10 mW / cm ² ).
Exposure can be performed by irradiating for about 15 seconds.

The developing treatment is to remove the solubilized portion y of the ceramic layer molded body 11e with a developing solution.
1,1-Trichloroethane is developed by a spray method.
Thereafter, unnecessary debris and the like generated by development of the ceramic layer molded body 11e are completely removed by a washing and drying process.

Next, as shown in FIG.
0 is filled with a conductive paste by a screen printing method and dried to form a conductive member 21, and a pattern 31 serving as an internal wiring 3 disposed between the ceramic layers 1 d and 1 e is screen printed and dried. To form.

The conductive paste of the conductor material to be used as the internal wiring and via-hole conductor is made of a powder of at least one metal material of gold, silver, copper or an alloy thereof, a low-melting glass component, an organic binder and an organic solvent. A homogeneously kneaded mixture is used. In particular, when the firing temperature is 850 to 1050 ° C., a relatively low melting point and low resistance material is selected as the metal material, and the low melting point glass component is also selected.
Taking into account the sintering behavior of a ceramic layer molded body (a material coated with a slip material and dried) to be a ceramic layer, one having a deformation point of about 700 ° C. is used.

Next, FIGS. 3B to 3D are repeated again, and as shown in FIG. 3E, the conductive member 21 to be the via-hole conductor 2 and the ceramic to be the ceramic layer 1d on which the pattern 31 is formed. The layer molded body 11d is formed.

Next, a ceramic layer molded body 11c including an opening 40 for forming a cavity to be the cavity 4 is formed.

First, a photo target in which a portion to be the through hole 20 for the via-hole conductor 2 and the opening 40 for forming the cavity is light-shielded is placed on the ceramic layer molded body 11c, and an ultra-high pressure mercury lamp (10 mW / cm) is placed. ² ) is used as a light source for exposure, the solubilized portion y is spray-developed with 1,1,1-trichloroethane, and further washed and dried to form a through hole 20 and a through hole 20 as shown in FIG. An opening 40 is formed.

Next, as shown in FIG. 3G, a resin paste containing a photo-curable monomer or a thermo-curable monomer is filled into the opening 40 by a screen printing method or the like.

As the photocurable monomer contained in the resin paste, a resin having good thermal decomposability, such as an alkyl methacrylate similar to the photocurable monomer contained in the slip material for forming the ceramic layer, is used. When a thermosetting monomer is used, an acrylate-based unsaturated polyester resin is desirable.

Next, the resin paste filled in the opening 40 is subjected to an exposure process or a heating process to cure the resin paste. When the resin paste containing the photocurable monomer is cured, the entire resin paste is exposed to light and cured using the same exposure apparatus as that used to form the through holes 20 (the exposure amount is 10 mW / cm ² ). The light source is irradiated for 10 to 20 seconds). When a resin paste containing a thermosetting monomer is cured, a batch drying oven or the like is used.
The resin paste is cured by heating at 20 ° C. for 10 minutes. Here, the reason for curing the resin paste is to prevent the permeation of the components into the resin 41 when the next layer of the slip material is applied on the filling resin.

In fact, when the slip material of the next layer is applied without curing the resin paste, the mixture of the ceramic powder and the binder in the slip material penetrates deeply into the resin paste, and the permeated components are Is not removed by the development process described above, and is not removed even if the resin charged during baking is burned off, remains in the formed opening 40, and adversely affects the substrate characteristics.

Thereafter, a conductive paste is filled into the through-holes 20 of the ceramic layer molded body 11c to form a conductive member 21 to be the via-hole conductor 2, and further a pattern 31 to be the internal wiring is formed. A laminated molded article as shown in (1) is prepared.

Subsequently, as shown in FIGS. 3 (i) and 3 (j), the ceramic layer molded body 11b which becomes the ceramic layer 1b and the ceramic layer molded body 11a which becomes the ceramic layer 1a are formed on the ceramic layer molded body 11c. The same processing as that of the ceramic layer molded body 11c is repeated to obtain a laminated molded body having a cavity forming opening 40 filled with the resin 41 to a depth of three layers as shown in FIG. . still,
In the present embodiment, the number of layers is five, but the number of layers and the depth of the opening for forming the cavity are arbitrary. The depth of the opening may be two ceramic layers.

Next, the supporting substrate 7 is removed, and the laminated molded body 11 shown in FIG. 3 is completed. Then, if necessary, the shape of the laminated molded body 11 is adjusted by pressing, or a division groove is formed.

Next, firing is performed. The firing includes a binder removal step and a main firing step. The binder removal step is performed in a temperature range of about 600 ° C. or less, and the ceramic layer molded bodies 11 a to 11 e and the pattern 31, the organic binder contained in the conductive member 21, the photocurable monomer, and the opening 40 are filled. The main baking step is a baking step with a peak temperature of 850 to 1050C, for example, a peak at 900C for 30 minutes.

Thus, as shown in FIG. 1, the via-hole conductor 2, the internal wiring 3 and the cavity 4 are formed between the five ceramic layers 1a to 1e, and the base 1 on which the surface wiring 5 is formed is completed. . Thereafter, as a surface treatment, printing and baking of the thick film resistive film 8 and the thick film protective film, plating, and bonding of the electronic component 6 including the IC chip are further performed.

The surface wiring 5 may be printed and dried on the surface of the fired substrate 1 of the ceramic layer molded bodies 11a to 11e and baked in a predetermined atmosphere. For example, when an Ag-based conductor is used for the internal wiring 3 and a Cu-based conductor is used for the surface wiring 5, the ceramic layer molded bodies 11a to
11e and a laminate composed of the conductor film of the internal wiring 3 are fired in an oxidizing atmosphere or a neutral atmosphere, and the surface of the fired laminate is printed and dried with a Cu-based conductor to obtain a neutral atmosphere or a reducing atmosphere. Sintering is performed at a temperature of 780 ° C. or less (eutectic point of Ag and Cu) in an atmosphere.

When an alumina ceramic substrate is used as the support substrate 7, it may be left as a lower layer of the laminated ceramic substrate without being removed before firing. In this case, via-hole conductors and internal wiring patterns may be formed in advance on the alumina ceramic substrate as the support substrate 7.

Embodiment 2 In the above embodiment, three cavity openings are formed from the front side, but cavity openings of one to three layers may be formed on the back side. In this case, for example, FIG.
As shown in (i), the ceramic layer molded body 11e is exposed to light while shielding the through-hole 20 and the cavity forming opening 40 from light, and then subjected to development processing to form the cavity forming opening 40. Is filled with the above-mentioned resin paste, the through-hole 20 is filled with a conductive paste, and
Are printed to form ceramic layer molded bodies 11c, 11d and 11
e, and the ceramic layer molded bodies 11a, 11b
In the same manner as in Example 1, the opening 40, the pattern 31,
The conductive member 21 is formed, and the laminated molded body 11 is manufactured. Finally, it is fired to complete a multilayer ceramic substrate having cavities 4 on both sides.

[0069]

As described above, according to the present invention, a cavity having an arbitrary depth and shape can be easily formed with high accuracy, and the mounting accuracy of an electronic component on a multilayer ceramic substrate is improved. In addition, a highly accurate cavity can be formed on the back surface of the substrate, and the degree of freedom in designing the multilayer ceramic substrate can be increased.

[Brief description of the drawings]

FIG. 1 is a sectional view of a multilayer ceramic substrate according to the present invention.

FIG. 2 is a cross-sectional view of a laminated molded article according to the present invention.

FIG. 3 is a process flowchart illustrating a method for manufacturing a multilayer ceramic substrate according to the present invention.

FIG. 4 is a process flowchart illustrating a method for manufacturing a multilayer ceramic substrate of the present invention having cavities on both surfaces of the substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 11 ... Multi-layer molded body 1a-1e ... Ceramic layer 11a-11e ... Ceramic layer molded body 2 ... Via-hole conductor 20 ... ··· Through-hole 21 ····· Conductive member 3 ····· Internal wiring 31 ··· Pattern 4 ····· Cavity 40 ··· For cavity formation Opening 41 of resin filled in opening 5 Surface wiring 6 Electronic component 7 Support substrate x ..Insolubilized part y ... Solubilized part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akira Imoto 1-4-4 Yamashita-cho, Kokubu-shi, Kagoshima Inside the Kyocera Research Institute

Claims (2)

[Claims] 1. A method for manufacturing a multilayer ceramic substrate comprising a substrate formed by laminating a plurality of ceramic layers and a cavity for accommodating an electronic component formed on a surface of the substrate, comprising the following steps (a) to (g):
A method for manufacturing a multilayer ceramic substrate, comprising the steps of: (A) a step of producing a ceramic slip containing at least a photocurable monomer; (b) a step of thinning and drying the ceramic slip to form a ceramic layer molded body; and (c) exposing the ceramic layer molded body to light. Apply development processing,
Forming a cavity opening in a part of the ceramic layer molded body and curing the ceramic layer molded body; and (d) providing a light or heat curable monomer to the cavity opening in the ceramic layer molded body. Filling the resin paste containing the resin paste and curing the resin paste by exposure or heating. The surface of the ceramic layer molded body obtained in the steps (e) and (d) and the resin cured in the cavity opening is formed on the surface. Step of applying a ceramic slip and drying to form a ceramic layer molded body (f) With respect to the ceramic layer molded body formed in the step (e), (c), (d), and (e) are sequentially performed. A step of repeatedly producing a laminated molded body in which a plurality of the ceramic layer molded bodies are laminated (g) heating the laminated molded body to form a laminate inside the cavity opening; A step of forming an electronic component storage cavity by scattering resin. 2. The resin filled in the cavity opening,
2. The method according to claim 1, wherein the decomposition is performed at a temperature of 600 [deg.] C. or less.