JP5709732B2 - Manufacturing method of ceramic multilayer substrate - Google Patents

Description

  The present invention relates to a method for manufacturing a ceramic multilayer substrate used in a wiring board for mounting electronic components, chip-shaped electronic components, and the like.

  Conventionally, ceramic substrates such as aluminum oxide sintered bodies are used as wiring boards used for mounting electronic components such as semiconductor elements, and substrates for forming chip-shaped electronic components such as ceramic multilayer chip inductors. A ceramic multilayer substrate formed by laminating a plurality of insulating layers made of a body is often used. The ceramic multilayer substrate is manufactured by laminating and firing a plurality of ceramic green sheets obtained by bonding ceramic powder such as aluminum oxide with an organic binder.

  Conductive patterns such as wiring conductors and capacitive electrodes are provided on the main surface and side surfaces of the insulating layer forming the ceramic multilayer substrate. The conductor pattern is formed by applying a paste of a metal material such as tungsten on the surface of the ceramic green sheet and firing it simultaneously with the ceramic green sheet.

  That is, the conventional method for manufacturing a ceramic multilayer substrate includes a step of producing a plurality of ceramic green sheets, a step of applying a metal paste in a predetermined pattern on the surface of these ceramic green sheets, and laminating these ceramic green sheets And a step of integrally firing. In the stacking step, pressure is applied in the stacking direction in order to improve the adhesion between the upper and lower ceramic green sheets. That is, a pressurizing process is also included.

  In this case, since a metal paste layer having a certain thickness is interposed between the upper and lower ceramic green sheets, there is a possibility that the adhesion between the upper and lower ceramic green sheets may be lowered at the portion where the metal paste is applied. is there. In contrast, there is a technology in which a low elastic layer containing wax is provided on a ceramic green sheet, and the thickness of the metal paste is absorbed by the deformation of the low elastic layer to improve the adhesion between the upper and lower ceramic green sheets. Proposed.

Japanese Patent Laid-Open No. 61-229551

  However, in the conventional manufacturing method in which the low-elastic layer containing the wax is provided, when a plurality of ceramic green sheets are laminated, pressure is repeatedly applied. There is a problem that it is easily deformed, that is, it is easy to flow in a direction parallel to the main surface of the ceramic green sheet. When such deformation occurs, a part of the low elastic layer, that is, a part of the insulating layer after firing may be pushed out (protruded) to the outer surface of the laminate. In such a case, for example, the conductor pattern formed on the outer surface may be broken due to the pressure accompanying the protrusion. Moreover, there is a possibility that defects in dimensions and appearance as a ceramic multilayer substrate may occur.

The present invention has been completed in view of such conventional problems, and its purpose is to provide high adhesion between the upper and lower insulating layers and a part of the insulating layer from the interlayer of the insulating layer to the outer surface. It is an object of the present invention to provide a method for manufacturing a ceramic multilayer substrate capable of suppressing problems such as protrusions.

A method for producing a ceramic multilayer substrate according to one aspect of the present invention includes a step of producing a first ceramic green sheet layer containing a first resin material;
A second resin material having a lower elastic modulus than the first resin material at the first temperature and a second temperature higher than the first temperature are cured on the lower surface of the first ceramic green sheet layer. A second ceramic green sheet layer including a third resin material to be adhered is attached to the first layer including the first resin material, the second resin material, and the second resin material including the third resin material. Producing a plurality of two-layer ceramic green sheets having a two-layer structure comprising layers;
Printing a metal paste on the upper surface of one of the two-layer ceramic green sheets;
At the first temperature, the other two-layer ceramic green sheet is laminated on the upper surface of one of the two-layer ceramic green sheets, and the metal paste printed on the upper surface of one of the two-layer ceramic green sheets is Intruding into the second layer of the two-layer ceramic green sheet of
And a step of heating a laminate of one of the two-layer ceramic green sheets and the other two-layer ceramic green sheets at the second temperature to cure the third resin material.

  According to the method for producing a ceramic multilayer substrate of one aspect of the present invention, the first resin and the second resin are contained in the second layer that includes the above steps and forms a two-layer ceramic green sheet. It is possible to provide a method for manufacturing a ceramic multilayer substrate that has high adhesion between upper and lower insulating layers and can suppress problems such as protrusion of a part of the insulating layer from the insulating layer to the outer surface. it can.

  That is, since the two-layer ceramic green sheet has the second layer having a relatively low elastic modulus, a plurality of two-layer ceramics coated with the metal paste at the first temperature, in other words, at a lower temperature. When the green sheets are laminated, the second layer of the upper two-layer ceramic green sheet is deformed according to the thickness and shape of the metal paste printed on the upper surface of the lower two-layer ceramic green sheet. Therefore, it is easy to improve the adhesion between the upper and lower two-layer ceramic green sheets, and a ceramic multilayer substrate having high adhesion between the insulating layers can be manufactured.

  In addition, since the second layer contains the second resin that cures at the second temperature, in other words, at a higher temperature, the second resin is cured after the upper and lower two-layer ceramic green sheets are laminated. The elastic modulus of the second layer can be made higher than that during the lamination. Therefore, even if the lamination is repeated, the deformation of the second layer is effectively suppressed, and it is possible to suppress a part of the insulating layer from projecting to the outer surface of the ceramic multilayer substrate after firing.

It is sectional drawing which shows the ceramic multilayer substrate manufactured with the manufacturing method of one aspect of this invention. (A)-(d) is sectional drawing which shows the manufacturing method of the ceramic multilayer substrate of 1 aspect of this invention in order of a process, respectively. (A) And (b) is sectional drawing which shows the manufacturing method of the ceramic multilayer substrate of one aspect of this invention in order of a process, respectively. It is sectional drawing which shows the modification in one process of the manufacturing method shown in FIG. 2 and FIG.

  A method for manufacturing a ceramic multilayer wiring board according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing an example of a ceramic multilayer substrate manufactured by the manufacturing method of one embodiment of the present invention. An adhesive layer 1b is provided on the lower surface of the base layer 1a to form an insulating layer 1, and a plurality of insulating layers 1 are laminated to form an insulating substrate 2. A ceramic multilayer substrate 10 is formed with a metallized layer 3 interposed between the insulating layers 1. The metallized layer 3 penetrates into the adhesive layer 1b of the insulating layer 1 laminated on the upper side. Therefore, the upper and lower insulating layers 1 are in good contact with each other without being obstructed by the metallized layer 3. The ceramic multilayer substrate 10 is, for example, a wiring board for mounting an electronic component (not shown) such as a capacitive element or a piezoelectric element or a semiconductor element (not shown) such as a semiconductor integrated circuit element, or a ceramic multilayer chip inductor. It is used as a substrate for forming chip-like electronic components (not shown) such as.

  The insulating layer 1 (base layer 1a and adhesive layer 1b) is formed of a ceramic sintered body such as an aluminum oxide sintered body or a glass ceramic sintered body. The metallized layer 3 is formed of a metal material such as tungsten, copper, or silver. The insulating layer 1 and the metallized layer 3 are integrated by simultaneous firing. A through conductor (not shown) penetrating the insulating layer 1 in the thickness direction may be formed in the insulating layer 1. The through conductor is formed, for example, to electrically connect the upper and lower metallized layers 3 to each other.

  The base layer 1a is a main constituent material that ensures the mechanical strength and the like of the insulating layer 1, and the adhesive layer 1b is an auxiliary constituent material for enhancing the adhesion between the upper and lower insulating layers 1. Since the metallized layer 3 enters the adhesive layer 1b, the adhesion between the upper and lower insulating layers 1 is enhanced.

  In such a ceramic multilayer substrate, first, a plurality of ceramic green sheets to be the insulating layers 1 are produced, and then a metal paste to be the metallized layer 3 is printed on the upper surface of each ceramic green sheet, and then the metal It can be manufactured by laminating a plurality of ceramic green sheets printed with paste to form a laminate, and then firing the laminate.

  2 (a) to 2 (d) and FIGS. 3 (a) and 3 (b) are cross-sectional views showing a method of manufacturing a ceramic multilayer substrate in the embodiment of the present invention in the order of steps.

  First, as shown in FIG. 2A, a first ceramic green sheet layer 11 containing a first resin material is produced. The first ceramic green sheet layer 11 is produced by, for example, combining ceramic powder forming the insulating layer 1 such as aluminum oxide with an organic binder and forming it into a sheet shape. The first resin material is, for example, an organic binder that binds ceramic powder.

  As the first resin material, those conventionally used for ceramic green sheets can be used. For example, acrylic (a homopolymer or copolymer of acrylic acid, methacrylic acid or esters thereof, specifically acrylic ester copolymer, methacrylic ester copolymer, acrylic ester-methacrylic ester copolymer Etc.), polyvinyl butyral, polyvinyl alcohol, acrylic-styrene, polypropylene carbonate, and cellulose polymers. The polymer may be either a homopolymer or a copolymer.

  The first resin material is more preferably an acrylic binder in consideration of decomposition and volatility in the baking step described later.

  As the ceramic powder, the above-mentioned ceramic material powder and glass material powder forming the insulating layer 1 can be used. For example, if the insulating layer 1 is made of an aluminum oxide sintered body, powders such as aluminum oxide, silicon oxide, and calcium oxide are mixed with an organic solvent such as toluene and a binder (first resin material) such as acrylic polymer. The first ceramic green sheet layer 11 can be produced by forming a slurry prepared by kneading into a sheet shape by a doctor blade method or the like.

  Next, as shown in FIG. 2B, a second resin material having a lower elastic modulus than the first resin material at the first temperature is formed on the lower surface of the first ceramic green sheet layer 11, and the first A second ceramic green sheet layer 12 containing a third resin material that cures at a second temperature higher than the second temperature is deposited. As a result, as shown in FIG. 2C, the two-layer structure 2 is composed of the first layer 11a containing the first resin material and the second layer 12a containing the second resin material and the third resin material. A layer ceramic green sheet 21 is produced. A two-layer ceramic green sheet (hereinafter referred to as “ceramic green sheet”) 21 is fired in a later step to become the insulating layer 1 of the ceramic multilayer substrate 10. The first layer 11a of the ceramic green sheet 21 becomes the base layer 1a of the insulating layer 1, and the second layer 12a becomes the adhesive layer 1b of the insulating layer 1. A plurality of ceramic green sheets 21 are produced so as to correspond to the plurality of insulating layers 1.

  The same powder (aluminum oxide, silicon oxide, etc.) as that used for producing the first ceramic green sheet layer 11 should be used as the powder for producing the second ceramic green sheet layer 12. it can. The second ceramic green sheet layer 12 can be produced by forming such a powder into a sheet by the same method as described above.

  When the second ceramic green sheet layer 12 is produced, at least one of the second resin material and the third resin material may be used as a binder, and other than the second resin material and the third resin material. Another resin material may be used as a separate binder. For example, an acrylic resin similar to the first resin material can be used as the other resin material.

  The first ceramic green sheet layer 11 and the second ceramic green sheet layer 12 are attached, for example, by first forming a band-shaped green sheet (not shown) including a plurality of regions to be the first ceramic green sheet layer 11. Then, a belt-like green sheet (not shown) including a plurality of regions to be the second ceramic green sheet layer 12 can be formed thereon. Thereafter, the two-layered ceramic green sheet 21 can be produced by cutting the two-layered strip-shaped sheet into a predetermined size.

  The first temperature is, for example, a temperature when the ceramic green sheets 21 are stacked one above the other in a later step, and is about 40 to 70 ° C. The first temperature is preferably set to a temperature higher than the so-called normal temperature (25 ° C.), and more preferably higher than the temperature in summer (for example, about 35 ° C.). This is because, for example, the storability of the produced ceramic green sheet 21 or the ease of handling and workability in printing a metal paste to be described later is increased. The second temperature is a temperature at which the stacked body of the plurality of ceramic green sheets 21 stacked in the upper and lower directions in the subsequent step is heated, and is about 80 to 120 ° C.

  The second resin material included in the second ceramic green sheet layer 12 is a resin material such as wax having fluidity at the first temperature. This second resin material is a component for keeping the elastic modulus of the second layer 12a of the ceramic green sheet 21 small at the temperature at the time of lamination.

  As the second resin material, wax can be used as described above, and examples thereof include hydrocarbons, fatty acids, esters, aliphatic alcohols and polyhydric alcohols. The second resin material is more preferably an aliphatic alcohol and a polyhydric alcohol that do not contain a double bond, considering decomposition and volatility in a baking step described later.

  The third resin material included in the second ceramic green sheet layer 12 is a resin material that cures at a second temperature higher than the first temperature. This second resin material is a component for increasing the elastic modulus in the second layer 12a of the ceramic green sheet 21 after the lamination. That is, the second layer 12a of the ceramic green sheet 21 has a low elastic modulus and is flexible when laminated by being heated to the first temperature, and is then cured by being further heated to the second temperature. The elastic modulus increases and it becomes difficult to deform. The configuration and effect of the second layer 12a having such characteristics will be described in detail later.

  As the third resin material, the second resin material is not cured at the first temperature at which the second resin material exhibits fluidity (begins to show), and is cured at the second temperature higher than the first temperature. Can be used. Specifically, a resin that forms a crosslinked structure (so-called three-dimensional network structure) is applicable, and includes hydroxyl group or amino group-containing acrylic resin, isocyanate resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy. Resins and silicon resins or a mixture of these resins can be used.

  In order to improve the aging stability of the ceramic green sheet 21, a curing agent (not shown in FIGS. 2 and 3) must be attached by making the third resin material reactive with two liquids. It is also possible to prevent the curing reaction from starting. Specifically, it is possible to use a resin material capable of forming a crosslinked structure by a urethane bond, in which an isocyanate resin reacts (urethane reaction) with an acrylic resin to which a hydroxyl group or an amino group has been added to form a crosslinked structure. .

  Next, as shown in FIG. 2D, a metal paste 13 is printed on the upper surface of one of the plurality of ceramic green sheets 21 (21A).

  The metal paste 13 is fired in a later step to become the metallized layer 3. The metal paste 13 is prepared by kneading a powder of a metal material such as tungsten, molybdenum, or copper that forms the metallized layer 3 together with an additive such as an organic solvent and a binder as described above.

  The metal paste 13 is printed on the surface of the ceramic green sheet by, for example, a screen printing method. The printing thickness of the metal paste 13 is, for example, about 5 to 30 μm. Further, the viscosity of the metal paste 13 may be appropriately set according to printing conditions such as the line width and printing thickness of the pattern to be printed, and workability and economy.

  Next, as shown in FIG. 3A, another ceramic green sheet 21 (21B) is laminated on the upper surface of one ceramic green sheet 21 (21A) at the first temperature (for example, about 50 ° C.). . In the lamination, the metal paste 13 printed on the upper surface of one ceramic green sheet 21 (21A) is allowed to enter the second layer 12a of the other ceramic green sheet 21 (21B).

In other words, when the two layers of ceramic green sheets 21 are stacked one above the other, the thickness of the metal paste 13 printed on the upper surface of the lower ceramic green sheet 21 is set to the second layer on the lower surface side of the upper ceramic green sheet 21. Absorbs by deformation of 12a. Ie metal paste
In accordance with the thickness and shape of 13, the second layer 12a having a relatively low elastic modulus is deformed.

  Thereby, it is possible to suppress the obstruction by the metal paste 13 and improve the adhesion between the upper and lower ceramic green sheets 21. In order to obtain such an effect, it is desirable that the complex elastic modulus in the dynamic viscoelasticity measurement at a frequency of 1 Hz or less of the second layer 12a at the first temperature is 10 MPa or less.

  For example, as shown in FIG. 3A, the metal paste 13 may be printed on the upper surface of another ceramic green sheet 21 (21B) laminated on the upper side.

  When the two ceramic green sheets 21 are stacked up and down, pressurization is performed in the vertical direction (stacking direction) in order to improve the adhesion between the ceramic green sheets. By this pressurization, the metal paste 13 printed on the upper surface of one ceramic green sheet 21 (21A) is allowed to enter into the second layer 12a of the other ceramic green sheet 21 (21B) laminated thereon, that is, pushed. be able to.

  As described above, since the second resin material having a smaller elastic modulus than the first resin material at the first temperature is added to the second layer 12a, the elasticity of the second layer 12a at the first temperature. The rate can be made lower than the elastic modulus of the first layer 11a.

  The elastic modulus of the second resin material is low at the first temperature because, for example, the second resin material has a melting point at the first temperature, so that the second resin material is heated to the first temperature. Realized by flowing.

  Next, the laminate 22 of one ceramic green sheet 21 (21A) and another ceramic green sheet 21 (21B) is heated at the second temperature to cure the third resin material.

  As described above, since the third resin material that is cured at the second temperature is added to the second layer 12a, the third resin material is cured at the second temperature than before the curing. It is possible to increase the elastic modulus of the second layer 12a.

  When the third resin material is cured, the elastic modulus of the second layer 12a is increased as described above (about 100 to 1000 MPa), and deformation due to the external force of the second layer 12a is suppressed.

  By suppressing the deformation of the second layer 12a in this way, for example, the ceramic green sheet 21 is repeatedly laminated and pressed, so that the number of layers of the ceramic green sheets 21 (21A, 21B) or more is increased. It is possible to effectively suppress deformation of the second layer 12a due to pressurization when a green sheet laminate is produced.

  That is, the second layer 12a has a characteristic that it can be easily made flexible when the upper and lower ceramic green sheets are laminated and can hardly be deformed after the lamination is finished. Therefore, while ensuring good adhesion between the upper and lower ceramic green sheets 21 (21A, 21B), the ceramic green sheet 21 (particularly the second layer 12a) is also prevented from protruding outside the laminate. can do.

  The temperature at which the third resin material is cured is desirably a temperature that is higher by 20 ° C. or more than the first temperature at which the second resin material exhibits low elasticity due to melting or the like. . In other words, the second temperature is desirably 20 ° C. or higher than the first temperature.

When the difference between the first temperature and the second temperature is as small as less than 20 ° C., for example, the elastic modulus of the second layer 12a is lowered by melting the second resin material, and the metal paste 13 There is a possibility that the third resin material starts to be cured while entering the ceramic green sheet 21B (second layer 12a). In this case, it is difficult to obtain a desired elastic modulus for the second layer 12a, and there is a possibility that poor stacking (such as poor adhesion between the upper and lower ceramic green sheets 21) may occur.

  The above-described lamination and pressurization of the ceramic green sheet 21 on which the metal paste 13 is printed are performed according to the number of the insulating layers 1 in the ceramic multilayer substrate 10 to be manufactured, and as shown in FIG. If the laminate 22 is fired after the laminate having the number of layers is manufactured, for example, a ceramic multilayer substrate 10 as shown in FIG. 1 can be manufactured.

  In addition, in the laminated body 22 shown in FIG.3 (b), the lowest layer has laminated | stacked only the 1st layer 11a. Since the metal paste 13 does not exist below the lowermost layer, the second layer 12a need not be laminated.

  A ceramic green sheet 21 formed in a frame shape is laminated on the uppermost layer of the laminate 22. By laminating the frame-shaped ceramic green sheet 21 on the uppermost layer of the laminate 22, a recess can be formed on the upper surface of the laminate 22. Thereby, the recessed part (so-called cavity) for electronic component accommodation etc. can be provided in the upper surface of the insulated substrate 2 after baking.

  According to such a manufacturing method, since the adhesiveness between the upper and lower ceramic green sheets 11 is good, a ceramic multilayer substrate having excellent adhesiveness between the insulating layers 1 after firing can be manufactured. Further, according to this manufacturing method, it is possible to effectively suppress a part of the insulating layer 1 from protruding from the interlayer of the insulating layer 1 to the outer surface of the multilayer body 22 in the manufactured ceramic multilayer substrate. .

In the above manufacturing method, the thickness of the ceramic green sheet 21 may be appropriately set in consideration of the thickness of the insulating layer 1 and the shrinkage ratio during firing. For example, when manufacturing a ceramic multilayer substrate having an insulating layer 1 made of an aluminum oxide sintered body used for a wiring board for mounting electronic components, the thickness of the ceramic green sheet 21 is about 20 to 300 μm.
Should be set.

In this ceramic green sheet 21, when the thickness of the second layer 12a is set to a desired thickness, the difference between the thickness of the entire ceramic green sheet 21 and the thickness of the second layer 12a is set as the thickness of the first layer 11a. Good. The thickness of the second layer 12a is preferably a thickness that allows the metal paste 13 to enter inside, and is, for example, about 10 to 40 μm. In this case, the thickness of the first layer 11a may be set to about 10 to 260 μm. Second layer 12a is first
When the ratio of the resin components is larger than that of the layer 11a, it is desirable to set the thickness so as to ensure the minimum adhesiveness in the lamination in consideration of thermal decomposability.

  The thickness of the first layer 11a and the second layer 12a can be controlled to a predetermined thickness by adjusting the thickness of the first ceramic green sheet layer 11 and the second ceramic green sheet layer 12, respectively. The thickness of each of the first and second ceramic green sheet layers 11 and 12 can be set to a predetermined thickness by adjusting the molding thickness at the time of molding by the doctor blade method described above, for example.

At the first and second temperatures, the first layer 11a preferably has an elastic modulus of 100 MPa or more at the first temperature and the second temperature. Thereby, unnecessary deformation when the ceramic green sheets 21 are laminated can be more effectively suppressed.

  In the above manufacturing method, the third resin material added to the second ceramic green sheet layer 12 is preferably a two-component curable resin material of an uncured third resin material and a curing agent. Examples of the two-component curable resin material include a resin material capable of forming a crosslinked structure by urethane reaction as described above. Specifically, an acrylic resin to which at least one of a hydroxyl group and an amino group is added and an isocyanate resin can be used. In this case, when the hydroxyl group or amino group of the acrylic resin is cross-linked with the isocyanate resin, it becomes a urethane resin and curing is manifested. It can be considered that the acrylic resin is an uncured third resin material and the isocyanate resin is a curing agent.

  When the third resin material is of a two-component curing reactivity, it is difficult to cure unless the two components are mixed, and therefore unnecessary curing of the third resin material can be more easily suppressed. Therefore, for example, the change (time-dependent change) of the second ceramic green sheet 12 or the ceramic green sheet 21 having the second layer 12a in storage or the like can be more reliably suppressed.

  As the amount of the curing agent increases with respect to the third resin material, the curing of the third resin material proceeds, and the elastic modulus of the second layer 12a increases. On the contrary, as the amount of the curing agent decreases with respect to the third resin material, the curing of the second layer 12a is suppressed and the elastic modulus becomes smaller.

  Further, if the amount of the curing agent is excessively large, it cannot be thermally decomposed by firing, and a residue may remain to induce deterioration of porcelain characteristics. The amount of the curing agent (for example, the ratio of the isocyanate resin to the amount of the acrylic resin) may be appropriately determined for the third resin material in consideration of such points and economy.

  FIG. 4 is a cross-sectional view showing a modification in one step of the manufacturing method shown in FIGS. 4, parts similar to those in FIGS. 2 and 3 are given the same reference numerals. In the example shown in FIG. 4, the curing agent 14 is adhered to the lower surface of the second layer 12a in layers.

  If the curing agent 14 is adhered in layers in this way, the second layer 12a does not contain the curing agent 14 at the time of lamination, so that the elastic modulus of the second layer 12a can be more reliably kept small. . Further, by subsequently heating to the second temperature, the layered curing agent 14 is more uniformly diffused into the second layer 12a over almost the entire surface of the second layer 12a in plan view, and the second layer 12a The third resin material can be cured more uniformly and effectively. Therefore, deformation (compression) of the second layer 12a in pressurization after lamination can be prevented more reliably.

  In addition, since the curing of the second layer 12a can be more effectively caused by simply applying the curing agent 14 in layers, a method for producing a ceramic multilayer substrate that is excellent in productivity and economy is provided. be able to.

  The method for attaching the curing agent 14 in layers is, for example, as follows. That is, a solution obtained by diluting the curing agent 14 such as the isocyanate resin with a soluble solvent such as butyl acetate or a plasticizer may be prepared and applied to the lower surface of the second layer 12a by a method such as screen printing.

  In the above manufacturing method, the metal paste 13 may also contain a curing agent (not shown) of the third resin material. In this case, the hardening (crosslinking reaction) of the third resin material can be more efficiently promoted particularly in the portion around the metal paste 13, and the elastic modulus of the second layer 12a in this portion can be further increased. Can do.

  Therefore, in particular, the deformation of the second layer 12a in the periphery of the metal paste 13 where the deformation of the second layer 12a is likely to occur, that is, the portion where the metallized layer 3 is interposed between the layers of the insulating layer 1 is more effectively suppressed. Can do.

  As the curing agent to be added to the metal paste 13, for example, the same curing agent as the layer 14 attached to the lower surface of the second layer 12a can be used.

  The amount of the curing agent added to the metal paste 13 is appropriately set according to the conditions such as the printing thickness, area, viscosity, and elastic modulus at the first temperature of the metal paste 13 to satisfy the required flow rate. You only have to set it.

  As a manufacturing method of the examples, a plurality of ceramic green sheets are produced by bonding ceramic powders containing aluminum oxide as a main component and adding silicon oxide, calcium oxide and magnesium oxide with a binder, and laminating the ceramic green sheets. And then firing to produce a ceramic multilayer substrate.

In the above embodiment, the first resin material is methyl methacrylate-ethyl acrylate copolymer, the second resin material is hexadecanol, and the third resin material is methyl methacrylate-ethyl acrylate-hydroxyethyl acrylate copolymer. Polymerization was used. The third resin material was two-component curable, and hexamethylene diisocyanate was used as the curing agent. The first temperature was 50 ° C. and the second temperature was 100 ° C. The elastic modulus of the second resin material at the first temperature was about 2 MPa.

The ceramic green sheet produced by the manufacturing method of the example has a side length of about 200.
It was a square shape of mm, and the thickness was about 120 μm. The thickness of the first layer was about 20 μm, and the thickness of the second layer was about 100 μm.

A metal paste is printed on the top surface of this ceramic green sheet in a polygonal line pattern with a line width of 75μm and a thickness of about 15μm. Then, four layers of ceramic green sheets are stacked on top and bottom to produce a laminate, which is fired Thus, a ceramic multilayer substrate was produced. The metal paste was prepared using tungsten powder.

  In addition, as a comparative example, a ceramic green sheet using the first resin material as a binder was manufactured, and a ceramic multilayer substrate was manufactured in the same manner as in the above example except for this.

In both the manufacturing method of the example and the manufacturing method of the comparative example, the number of produced ceramic multilayer substrates was 100. In these ceramic multilayer substrates, the adhesion between the insulating layers was observed with a cross-section of the porcelain after firing, and the surface of the laminate was observed with a stereomicroscope to determine whether the insulating layer protruded from the outer surface.

  As a result, in the ceramic multilayer substrate produced by the production method of the example, neither a portion having low adhesion between layers nor a protrusion of the insulating layer was confirmed.

On the other hand, with respect to the ceramic multilayer substrate manufactured by the manufacturing method of the comparative example, adhesion failure was confirmed in 100% of the substrates, and part of the insulating layer protruded from the outer surface of the insulating substrate between 100% of the substrates. It was confirmed that

  By the above, in the manufacturing method of the Example of this invention, the effect which improves the adhesiveness of ceramic green sheets (insulating layer), and a part of laminated body (insulating substrate) outer surface of a ceramic green sheet (insulating layer) The effect which suppresses protrusion was able to be confirmed.

DESCRIPTION OF SYMBOLS 1 ... Insulating layer 1a ... Base layer 1b ... Adhesive layer 2 ... Insulating substrate 3 ... Metallizing layer
11 ··· First ceramic green sheet layer
11a ... 1st layer
12 ... Second ceramic green sheet layer
12a ... 2nd layer
13 ... Metal paste
14 ... Hardener
21 ... 2 layer ceramic green sheet (ceramic green sheet)
21A: One ceramic green sheet
21B ... Other ceramic green sheets
22 ... Laminate

Claims (3)

Producing a first ceramic green sheet layer containing a first resin material;
A second resin material having a lower elastic modulus than the first resin material at the first temperature and a second temperature higher than the first temperature are cured on the lower surface of the first ceramic green sheet layer. A second ceramic green sheet layer including a third resin material to be adhered is attached to the first layer including the first resin material, the second resin material, and the second resin material including the third resin material. Producing a plurality of two-layer ceramic green sheets having a two-layer structure comprising layers;
Printing a metal paste on the upper surface of one of the two-layer ceramic green sheets;
At the first temperature, the other two-layer ceramic green sheet is laminated on the upper surface of one of the two-layer ceramic green sheets, and the metal paste printed on the upper surface of one of the two-layer ceramic green sheets is Intruding into the second layer of the two-layer ceramic green sheet of
And a step of heating a laminate of one of the two-layer ceramic green sheets and another of the two-layer ceramic green sheets at the second temperature to cure the third resin material. A method for producing a multilayer substrate. The third resin material is a two-component curable resin material of the uncured third resin material and a curing agent, and the curing agent is applied to the lower surface of the second layer of the two-layer ceramic green sheet. The method for producing a ceramic multilayer substrate according to claim 1, further comprising a step of adhering in a layer form. 3. The method for manufacturing a ceramic multilayer substrate according to claim 2, wherein the curing agent is contained in the metal paste before the third resin material is cured.

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