JP2003037022A - Laminated electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent bending, delamination, and occurrence of cracks in a product without using a sandwich structure in a laminated electronic component in which material layers of different kinds are bonded and integrally sintered. SOLUTION: A dielectric layer incorporating a conductor layer and a magnet layer incorporating a conductor layer are laminated, and a layer that is made of the same material as the dielectric layer or the magnet layer but does not incorporate a conductor layer is laminated on one surface or both surfaces of the laminate so that the dielectric layer and the magnet layer are alternately bonded. Furthermore, a bonding layer is laminated between the dielectric layer and the magnet layer, and a layer that is made of the same material as that of the bonding layer but does not incorporate a conductor layer further is bonded on the outer surface of the magnet layer. Furthermore, a glass is contained in any of the layers made of a dielectric material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated electronic component including an insulator such as a magnetic substance or a dielectric substance and a different material layer such as a conductor or a resistor, and particularly, a laminated composite inductor and a laminated composite capacitor. The present invention relates to an integrally sintered laminated electronic component including an LC filter and a hybrid integrated circuit board in which a chip component mounting layer is laminated on the upper layer and a wiring layer is laminated on the lower layer.

[0002]

2. Description of the Related Art In recent years, with the demand for miniaturization of electronic devices,
The electronic components that compose it are becoming more complex, lighter, thinner and smaller. For example, a capacitor layer having a high dielectric constant and a wiring layer having a low dielectric constant are laminated, and a chip-shaped LC filter in which an inductor formed in a magnetic layer and a capacitor layer formed in a dielectric layer are integrally sintered is used. It is used.

Such an LC filter is formed as follows. That is, an inductor layer in which a magnetic green sheet with an arbitrary number of coil conductors printed is connected to form a via hole connection, and a capacitor layer with a dielectric green sheet in which an arbitrary number of capacitor electrodes are printed are stacked and pressed. Then, they are pressure-bonded, cut into individual pieces, baked and integrally sintered, and terminal electrodes are baked on the outer surface to form a chip-shaped LC filter. At this time, since it is preferable to use a silver paste having good conductivity for the coil conductor and the capacitor electrode, a magnetic green sheet and a dielectric green sheet which are fired at a melting point of silver or less are used.

However, first, since it is difficult to approximate the rate of thermal expansion and the rate of thermal contraction between the magnetic layer and the dielectric layer, cracks 7 as shown in FIG.
When delamination 8 or warpage occurs, and secondly, when a reaction layer is formed at the interface between each material layer and the bonding layer or the dummy layer, the sintering shrinkage rate and the thermal expansion rate of this reaction layer portion change. Then, cracks, delamination, and warpage occurred. As a countermeasure, as shown in FIG. 8, a structure in which a bonding layer 4 having an average sintered shrinkage ratio and a thermal expansion coefficient between the magnetic layer 2 and the dielectric layer 1 is interposed, or as shown in FIG. A sandwich structure in which the magnetic layer 2 is sandwiched between the dielectric layers 1 has been used.

In the structure shown in FIG. 5, in order to connect the capacitor electrodes 9 of the upper and lower dielectric layers as shown in the sectional view of FIG. It is also possible to provide a relay)
Products with a large number of capacitors have an intermediate magnetic layer 2
Therefore, it is necessary to provide vias 11 for relaying, and therefore it is necessary to punch through holes in each layer of the magnetic material layer and imprint silver paste into the through holes. Further, in the intermediate magnetic layer 2, the effective area of each layer is reduced in proportion to the number of vias and the arrangement of the coil electrodes is limited. Therefore, the area of each layer is widened or the reduced effective area is laminated. Because we have to increase the number and increase the thickness of the product,
The size was large and the cost was high.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to suppress the occurrence of product warpage, delamination, and cracks in a laminated electronic component in which different material layers are joined and integrally sintered, and as described above. In the case of the sandwich structure, the cost is reduced by eliminating the connection by the external electrodes or the connection of the upper and lower layers on the side surface.

[0007]

According to the present invention, in a laminated electronic component made of different material layers, a dielectric layer containing a conductor layer and a magnetic layer containing a conductor layer are laminated, and the upper and lower surfaces of the laminate are laminated. At least one surface is laminated with a dummy layer made of the same material as the dielectric layer or the magnetic material and not containing a conductor layer and fired to bond the dielectric layers and the magnetic layers alternately.

As shown in the side view of the illustrative laminated electronic component according to the invention in FIG. 1, a dielectric layer 1 containing a conductor layer.
Then, a magnetic layer 2 containing a conductor layer is laminated, and a dummy layer 3 made of the same material as the dielectric layer and not containing a conductor layer is laminated on the lower surface of the magnetic layer and sintered. Further, when the reaction layers are formed on both layers of the interface between the dielectric layer 1 and the magnetic layer 2, as shown in FIG. 2, the conductor layer made of the same material as the magnetic layer 2 is not built in on the upper surface. The dummy layer 3 is disposed on the dielectric layer and the dielectric layers and the magnetic layers are alternately joined.

At the time of sintering, the stress due to the difference in the thermal contraction behavior or the difference in the coefficient of thermal expansion between the reaction layer formed at the joint surface between the dielectric layer containing the conductor layer and the magnetic layer containing the conductor layer is By providing a dummy layer on at least one of the upper and lower surfaces of the laminate to form a reaction layer and balance the stress of the reaction layer with each other, warpage, delamination, and crack generation are prevented.

Further, according to the present invention, in a laminated electronic component made of different material layers, a dielectric layer containing a conductor layer and a magnetic layer containing a conductor layer are laminated in the middle with a bonding layer, and a laminate is further formed. It is characterized in that a dummy layer made of the same material as the bonding layer and having no conductor layer is bonded to at least one of the upper and lower surfaces.

As shown in FIG. 3 or FIG. 4, a dielectric layer 1 containing a conductor layer and a conductor layer are built in for joining different materials having large differences in firing shrinkage behavior and thermal expansion coefficients. A dummy which is laminated between magnetic layers 2 via a bonding layer 4 having an average value of thermal contraction behavior or thermal expansion coefficient of both, and which is made of the same material as the bonding layer and does not include a conductor layer. The layer 3 is bonded to one side or both upper and lower sides of the laminate. A mounting pattern of chip components can be formed on the surface of the upper dummy layer of this laminated body, and a terminal electrode may be formed on the surface of the lower dummy layer.

According to FIG. 3, when a reaction layer is formed at the interface between the bonding layer 4 and the magnetic layer 2, a dummy layer made of the same material as the bonding layer 4 is formed on the lower surface of the magnetic layer 2. Further, according to FIG. 4, when a reaction layer is further formed at the interface between the dielectric layer 1 and the bonding layer 4, a dummy layer of the same material as the bonding layer 4 is formed on the upper surface of the dielectric layer 1. Stress due to difference in firing shrinkage behavior or thermal expansion coefficient between dissimilar materials can be relaxed, and the stress can be balanced in the reaction layer with the outer dummy layer of the laminated body, suppressing warpage, delamination and crack generation. be able to.

Further, the present invention is characterized in that, in the above-mentioned laminated electronic component, glass is contained in a dummy layer which is the same material as the dielectric layer, the bonding layer and the dielectric layer and does not contain a conductor layer.

In the above-mentioned laminated electronic component, the sintering temperature can be lowered and the melting point of silver can be lowered by containing glass in the dummy layer which is made of the same material as the dielectric layer, the bonding layer and the dielectric layer and does not contain the conductor layer. The following low temperature firing becomes possible.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In a laminated electronic component composed of different material layers, a dielectric layer containing a conductor layer and a magnetic layer containing a conductor layer are laminated, and one side or both sides of the laminate are
Layers made of the same material as the dielectric layer or the magnetic material and not containing a conductor layer are laminated, and the dielectric layers and the magnetic layers are alternately joined.

In addition, a dummy layer, which is made of the same material as the bonding layer and does not contain a conductor layer, is laminated on at least one of the upper and lower surfaces of the laminated body in the middle of the dielectric layer and the magnetic layer via the bonding layer. , The dielectric layers and the magnetic layers are alternately laminated, fired and sintered. Further, glass is contained in the dielectric layer and the bonding layer.

[0017]

Example 1 Fe2O3 48 mol as a magnetic layer
%, NiO 6 mol%, CuO 10 mol%, Zn
Ni-Cu-Zn ferrite composed of O 36 mol%, BaO 12 mol% as a dielectric layer, TiO2
3 wt% of zinc borosilicate glass is added to the titanic acid-based composite oxide dielectric material consisting of 55 mol% and ZnO 33 mol%
%, A binder, a plasticizer and a solvent were added to each of the added materials and kneaded to prepare slips.

Next, each slip was formed into a green sheet having a thickness of 100 μm by the doctor blade method. Next, each of the obtained green sheets is punched out into a 10 cm square sheet together with a through hole for forming a via if necessary, so that a plurality of capacitor electrodes are provided on the dielectric sheet and a magnetic sheet to form an LC filter. A plurality of coil forming patterns were printed with silver paste to obtain a multi-cavity sheet.

Then, one of the dielectric green sheets is formed on the dummy layer 3 shown in the structure of FIG. 1, and the magnetic green sheet 18 is laminated on the magnetic layer 2 so as to form a coil.
14 sheets of dielectric green sheets laminated so as to form a capacitor on the dielectric layer 1 were laminated in this order to obtain a pressure-bonded laminated body. Next, after sintering, the product was cut and cut to allow for a shrinkage rate of 5 mm square, degreased and baked at 900 ° C. for 3 hours to obtain a product. At the same time, the same number of conventional products without the above-mentioned dummy layer were prepared.

For each of the 256 products of the present invention and the conventional structure described above, the defect rate in which the individual pieces in which delamination or cracks were generated were considered defective, and FIG.
The average value of the warp amount shown in Table 1 was measured by an image microscope.
Shown in.

[Table 1]

7 of materials used for the magnetic layer and the dielectric layer
Table 2 shows the firing shrinkage rate and the thermal expansion rate of the samples sintered at 00 ° C, 800 ° C, 900 ° C and 900 ° C for 3 hours. It can be seen that the difference in firing shrinkage and the difference in thermal expansion between the magnetic layer and the dielectric layer are sufficiently small.

[Table 2]

From the comparison results in Table 1, the effect of the present invention is clear, and it can be seen that the occurrence of delamination, cracks, and warpage, which could not be solved even by approximating the firing shrinkage ratio and the thermal expansion coefficient, is suppressed. .

The laminated electronic component according to the present invention is not limited to the above-mentioned embodiment, and can be realized by various materials within the scope of the spirit thereof. The magnetic material is not limited to the Ni-Cu-Zn ferrite described in the examples, but may be Ni-Cu.
A low temperature sintered ferrite such as a system, Cu-Zn system, or Mg-Cu-Zn system may be used. The dielectric is not limited to the BaO-ZnO-TiO2-based titanate-based composite oxide described in the examples, but titanium oxide-based, titanate-based composite oxide, zirconate-based composite oxide, or a mixture thereof may be used. You can Also, a sintering aid may be added to the dielectric. Specifically, as titanium oxide type, NiO, CuO,
TiO2 containing Mn3O4, etc., but BaTiO3, SrTiO3, CaTiO as titanic acid-based composite oxides.
3, MgTiO3, ZnTiO3, and the like, but as the zirconic acid-based complex oxide, BaZrO3, SrZrO3, Ca.
Examples thereof include ZrO3 and MgZrO3. Examples of the sintering aid include CuO, Bi2O3, V2O5, PbO and a mixture thereof.

[0024]

Example 2 Fe2O3 48 mol as a magnetic layer
%, NiO 6 mol%, CuO 10 mol%, Zn
Ni-Cu-Zn ferrite composed of O 36 mol%, BaO 16 mol% as a dielectric layer, and TiO2
67 mol%, Nd2O3 14 mol%, Bi2O3
A material obtained by adding 3 wt% of zinc borosilicate glass to a titanate-based composite oxide dielectric material consisting of 3 mol%, BaO 12 mol% and TiO 2 55 mol as a bonding layer.
%, ZnO 33 mol% titanic acid-based composite oxide dielectric material to which 3 wt% of zinc borosilicate glass was added, a binder, a plasticizer and a solvent were added and kneaded to prepare a slip.

Next, each slip was formed into a green sheet having a thickness of 100 μm by the doctor blade method. Next, each of the obtained green sheets is punched out into a 10 cm square sheet together with a through hole for forming a via if necessary, so that a plurality of capacitor electrodes are provided on the dielectric sheet and a magnetic sheet to form an LC filter. A plurality of coil forming patterns were printed with silver paste to obtain a multi-cavity sheet.

Next, one magnetic layer green sheet is formed on the dummy layer 3 shown in the structure of FIG. 3, and one magnetic layer green sheet is laminated on the magnetic layer 2 so as to form a coil.
One sheet, the above-mentioned joining layer green sheet on the joining layer 4, and 14 sheets of the dielectric green sheet laminated on the dielectric layer 1 so as to form a capacitor were sequentially laminated to obtain a pressure-bonded laminate. Next, after sintering, the product was cut and cut to allow for a shrinkage rate of 5 mm square, degreased and baked at 900 ° C. for 3 hours to obtain a product.
At the same time, as a comparative example, the same number of conventional products shown in FIG.

For each of the above-mentioned 256 products of the present invention and the conventional structure, the defect rate in which the individual pieces in which delamination or cracks occurred were regarded as defective, and FIG.
The average value of the warp amount shown in Table 3 is measured by an image microscope and the average value is shown in Table 3.
Shown in.

[Table 3]

Table 4 shows firing shrinkage and thermal expansion coefficients of the materials used for the magnetic layer, the dielectric layer and the bonding layer, which were sintered at 700 ° C., 800 ° C., 900 ° C. and 900 ° C. for 3 hours. Show. It can be seen that the differences in firing shrinkage and thermal expansion between the magnetic layer / junction layer and the dielectric layer / junction layer are sufficiently small.

[Table 4]

From the inspection results in Table 3, the effect of the present invention is clear, and the occurrence of delamination, cracks, and warping, which could not be solved even by continuously changing the firing shrinkage rate and the thermal expansion rate by using the bonding layer, occurred. You can see that it is suppressing.

[0030]

EFFECTS OF THE INVENTION In a laminated electronic component in which different material layers are joined and integrally sintered, warpage, delamination and cracks are prevented from being produced in the product, and a sandwich structure is not used, resulting in a large number of capacitors. Even in the product with the configuration, since the capacitors in the upper and lower layers are connected, there is no need for relaying by external electrodes, punching through holes in the intermediate layer, and the step of imprinting silver paste into the through holes, thus eliminating the reduction in effective area. It is possible to provide a small-sized and low-cost laminated electronic component.

[0031]

[Brief description of drawings]

FIG. 1 is a structural explanatory view of a laminated electronic component according to claim 1.

FIG. 2 is a structural explanatory view of the laminated electronic component of claim 1.

FIG. 3 is a structural explanatory view of the laminated electronic component of claim 2;

FIG. 4 is a structural explanatory view of the laminated electronic component of claim 2;

FIG. 5 is a structural explanatory view of a conventional laminated electronic component.

FIG. 6 shows an example of measuring the amount of warpage.

FIG. 7 shows a failure mode of a conventional laminated electronic component.

FIG. 8 is a structural explanatory view of a conventional laminated electronic component.

FIG. 9 is a structural cross-sectional view of a conventional laminated electronic component.

[Explanation of symbols]

1 Dielectric layer 2 Magnetic layer 3 Dummy layer 4 Bonding layer 5 Multi-layer electronic components 6 Warp amount 7 crack 8 delamination 9 Capacitor electrode 10 coil electrode 11 beer

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Claims (3)

[Claims] 1. In a laminated electronic component made of different material layers, a dielectric layer containing a conductor layer and a magnetic layer containing a conductor layer are laminated, and the dielectric is formed on at least one of the upper and lower surfaces of the laminate. A laminated electronic component, wherein a dummy layer made of the same material as a layer or a magnetic body and not containing a conductor layer is joined, and a dielectric layer and a magnetic layer are alternately joined. 2. In a laminated electronic component made of different material layers, a dielectric layer containing a conductor layer and a magnetic layer containing a conductor layer are laminated with a bonding layer in between, and the upper and lower surfaces of the laminate are laminated. A laminated electronic component comprising a dummy layer, which is made of the same material as that of the bonding layer and does not include a conductor layer, bonded to at least one surface. 3. The laminated electronic component according to claim 1, wherein the dielectric layer and the bonding layer contain glass.