JP2005268455A - Laminated electronic part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated electronic part that can ensure performance as an electronic part and wherein no crack occurs in a low magnetic part therein. <P>SOLUTION: A choke coil 1 is comprised of first and second coils 4 and 5, a low magnetic permeability part 6, and a low magnetic part 7. The first and second coils 4 and 5 are included in the low magnetic permeability part 6. The thickness T1 of a coil-to-coil low magnetic permeability layer 8 inserted between the first and second coils 4 and 5 is set to 0.04 to 0.14 times the total thickness T2 of the magnetic part 7. For example, when the total thickness T2 of the magnetic part 7 is 500 μm, the thickness T1 of the coil-to-coil low magnetic permeability layer 8 is set to a value ranging 20 μm or more to 70 μm or less. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multilayer electronic component such as a multilayer common mode choke coil.

Conventionally, regarding this type of laminated electronic component, there is a technique disclosed in Patent Document 1, for example.
This electronic component is a laminated common mode choke coil, and has a structure in which a pair of coils 101 and 102 are embedded in a low magnetic permeability portion 111 as shown in FIG. The low magnetic permeability portion 111 has an outer shape formed in a square ring shape along the coils 101 and 102, and a predetermined region including the winding axis inside the coils 101 and 102 is hollowed out. The low permeability portion 111 is entirely encased in a high permeability portion 112, and the hollow portion 112 a is filled with the high permeability portion 112.
Thus, by embedding the coils 101 and 102 in the low magnetic permeability portion 111, it is possible to ensure good noise removal characteristics as a common mode choke coil, and to apply a magnetic field inside the coils 101 and 102 to the inside of the hollow portion 112a. By passing through the high magnetic permeability portion 112, desired inductance characteristics and a good coupling coefficient are obtained.

JP-A-7-201569

However, the conventional multilayer electronic component described above has the following problems.
The above-mentioned multilayer electronic component is formed by pressure laminating by laminating an internal electrode conductor obtained by patterning a conductive material, a glass ceramic as a low magnetic permeability material, a ceramic green sheet, etc. on a ceramic green sheet that is a high magnetic permeability material. As a result, an unfired laminated body is formed and fired to form the coils 101 and 102, the low magnetic permeability portion 111, and the high magnetic permeability portion 112 shown in FIG. However, when the low magnetic permeability portion 111 has a ring shape, a crack may occur in the low magnetic permeability portion 111 during the above-described pressure-bonding lamination, and the reliability as an electronic component may be significantly impaired.
In addition, cracks generated in the low magnetic permeability portion 111 are difficult to detect from the appearance of the electronic component, and are also a fatal defect as an electronic component, and are difficult to repair. For this reason, in order to ensure the reliability of the multilayer electronic component as described above and to reduce the manufacturing cost, the low magnetic permeability portion 111 may be configured not to crack. It is strongly requested.

  The present invention has been made to solve the above-described problem, and eliminates the occurrence of cracks in the low magnetic permeability portion of a laminated electronic component such as a laminated common mode choke coil, thereby providing a highly reliable laminated film. An object is to provide a mold electronic component.

In order to solve the above-described problem, the multilayer electronic component according to the invention of claim 1 is configured such that the first coil and its winding axis coincide with the winding axis of the first coil. A second coil disposed at a distance from each other, and a predetermined region including the first and second coils and including the winding axis inside the winding of the first and second coils. A laminate type electronic component comprising a low magnetic permeability portion having a hollow portion formed by hollowing out and a magnetic body portion that fills the hollow portion and encloses the entire low magnetic permeability portion, wherein the low magnetic permeability portion Is interposed between the first coil and the second coil, and the inter-coil low magnetic permeability layer having a hole in the center, and the plurality of conductor pattern layers constituting the first coil. A plurality of conductor patterns constituting the second coil and the low permeability layer inserted and having a hole in the center portion And a low permeability layer having a hole in the center part, and being laminated in a state where the holes in the center part are connected so as to form a hollow part. The magnetic body portion is laminated by pressing between the upper and lower sides of the low magnetic permeability portion with a magnetic layer wider than the low magnetic permeability portion, and the thickness of the low magnetic permeability layer between the coils is the total thickness of the magnetic body portion. It was set as the structure which is 0.04 times or more and 0.14 times or less of this.
With this configuration, the multilayer electronic component functions as a common mode choke coil that removes noise between the first and second coils, the low magnetic permeability portion, and the magnetic body portion, and the first coil and the second coil. By using one of the coils as a primary coil and the other as a secondary coil, the coil also functions as a transformer. At this time, since the thickness of the low magnetic permeability layer between the coils is set to 0.04 times or more of the total thickness of the magnetic body portion, the withstand voltage between the first coil and the second coil Performance and reliability such as characteristics and durability are ensured.
The low magnetic permeability portion and the magnetic body portion are formed by pressure laminating a plurality of low magnetic permeability layers and a plurality of magnetic layers together with the conductor pattern layer. At this time, the thickness of the low magnetic permeability layer between the coils Is set to 0.14 times or less of the entire thickness of the magnetic body portion, so that even if a strong pressing force is applied during the pressure-bonding lamination, the low permeability portion is hardly cracked.

  According to a second aspect of the present invention, in the multilayer electronic component according to the first aspect, the low magnetic permeability portion has a magnetic permeability that is not more than 1/10 times the magnetic permeability of the magnetic body portion.

  According to a third aspect of the present invention, in the multilayer electronic component according to the first aspect, the low magnetic permeability portion has a magnetic permeability in the range of 1 to 10.

  According to a fourth aspect of the present invention, in the multilayer electronic component according to the first aspect, the low magnetic permeability portion is made of a nonmagnetic material having a magnetic permeability of about 1.

  According to a fifth aspect of the present invention, in the multilayer electronic component according to any one of the first to fourth aspects, the magnetic body portion is made of a magnetic body having a magnetic permeability of about 100.

  According to a sixth aspect of the present invention, in the multilayer electronic component according to the first aspect, the low magnetic permeability portion is made of glass ceramics.

  According to a seventh aspect of the present invention, in the multilayer electronic component according to any one of the first to sixth aspects, the magnetic part is made of Ni-Cu-Zn-based ferrite.

  As described above, according to the multilayer electronic component of the present invention, the upper limit of the thickness of the low magnetic permeability portion is optimized, so that the low magnetic permeability portion is sandwiched between the magnetic material layers from above and below and pressure-laminated. There is an excellent effect that cracks can be prevented from occurring in the low magnetic permeability portion. In addition, by optimizing the lower limit of the thickness of the low magnetic permeability portion, there is an effect that good durability and operational characteristics as a multilayer electronic component can be ensured.

  The best mode of the present invention will be described below with reference to the drawings.

    FIG. 1 is an external view of a multilayer electronic component according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view schematically showing a multilayer structure taken along the line AA in FIG. FIG. 2 is an exploded perspective view of the multilayer electronic component shown in FIG. 1.

  As shown in FIG. 1, the multilayer electronic component of this embodiment is a chip-shaped multilayer common mode choke coil (hereinafter simply referred to as “choke coil”), and includes a chip body 2 and four external terminals 3. −1 to 3-4.

  As shown in FIG. 2, the chip body 2 includes a first coil 4, a second coil 5, a low magnetic permeability portion 6, and a magnetic body portion 7, and these portions are as shown in FIG. 3. Four conductor patterns 41, 42 and 51, 52, five low magnetic permeability material sheets 61-66, five ceramic sheets 71-75 located in the lower part, and five ceramic sheets 76 located in the upper part. ˜80 are stacked in the order shown in FIG. 3, and then pressed and sintered.

As shown in FIG. 2, the first coil 4 and the second coil 5 are both contained in the low magnetic permeability portion 6 so that the winding axes L1 and L2 coincide with each other and have a predetermined distance. Are arranged apart from each other.
As shown in FIG. 3, the first coil 4 has a rectangular ring-shaped low-permeability with a square hole S2 in the center between conductor patterns 41 and 42 (conductor pattern layer) formed by patterning a conductive material. By inserting a magnetic material sheet 62 (low magnetic permeability layer) and connecting the conductor patterns 41 and 42 via via holes 62a provided in the low magnetic permeability material sheet 62, one coil is formed.
Similarly, the second coil 5 is a square ring-shaped low-permeability material sheet having a square hole S5 in the center between conductor patterns 51 and 52 (conductor pattern layer) formed by patterning a conductive material. By interposing 65 (low magnetic permeability layer) and connecting the conductor patterns 51 and 52 via via holes 65a provided in the low magnetic permeability material sheet 65, one coil is formed.
As the conductive material for forming the first and second coils 4 and 5, metals such as Cu, Pd, Al, and Ag excellent in conductivity, alloys thereof, and the like can be used.

The low magnetic permeability portion 6 is formed by pressure laminating low magnetic permeability material sheets 61 to 66 made of the same material and sintering them.
Specifically, the low magnetic permeability material sheets 63 and 64 have square holes S3 and S4, respectively, and the low magnetic permeability material sheets 63 and 64 are the first coil 4 and the second coil 5 respectively. (I.e., between the conductor pattern 42 and the conductor pattern 51 facing each other) to form the inter-coil low magnetic permeability layer 8. The low magnetic permeability material sheet 61 is interposed between the ceramic sheet 75 and the conductive pattern 41, and the low magnetic permeability material sheet 66 is interposed between the ceramic sheet 76 and the conductive pattern 52. These low magnetic permeability material sheets 61 and 66 also have square holes S1 and S6 having the same shape as the square holes S2 to S5, and the low magnetic permeability portion 6 is in a state where these square holes S1 to S6 are communicated with each other. All of the low magnetic permeability material sheets 61 to 66 are superposed, pressure laminated, and sintered. Thereby, the low magnetic permeability part 6 which has the three-dimensional hollow part V1 which the square holes S1-S6 connected was obtained.
As a low magnetic permeability material for forming the low magnetic permeability portion 6, a nonmagnetic material having a magnetic permeability of approximately 1 can be suitably used, such as glass ceramics. Alternatively, a material having a permeability of 1 to 10 or less, a material having a permeability of 1/10 or less of the permeability in the magnetic body portion 7, and the like can be used. Of course, it is not limited only to these.

  In this embodiment, as shown in FIG. 2, the thickness T1 of the inter-coil low magnetic permeability layer 8 after crimping is set to the total thickness of the magnetic body portion 7 described later (in other words, the entire chip body 2). The thickness T2) is set to a value within a range of 0.04 to 0.14 times. That is, 0.04 ≦ T1 / T2 ≦ 0.14. Specifically, when the thickness T2 of the chip body 2 is 500 μm, the thickness T1 of the inter-coil low magnetic permeability layer 8 is in the range of 20 to 70 μm, for example, 20 μm, 50 μm, and 70 μm. Set to one of the values.

As shown in FIG. 3, the magnetic part 7 is formed of lower ceramic sheets 71 to 75 and upper ceramic sheets 76 to 80. That is, the laminated conductor patterns 41, 42 and 51, 52 and the low magnetic permeability material sheets 61 to 66 are vertically moved by the ceramic sheets 71 to 75 and 76 to 80 wider than the low magnetic permeability material sheets 61 to 66. The magnetic body portion 7 is formed by crimping the entire structure and crimping the entire structure. Thereby, the magnetic body portion 7 encloses the entire low magnetic permeability portion 6 and fills the hollow portion V1 of the low magnetic permeability portion 6.
As the magnetic material forming the magnetic part 7, the above ceramic sheet (ceramic green sheet), Ni—Cu—Zn based ferrite, or the like can be suitably used. Or, quantitatively, a magnetic material having a magnetic permeability of 100 to 85 or more (more desirably 90 or more) is suitable. Of course, it is not limited only to these.

In the choke coil 1 having the above-described structure, if the portion interposed between the first coil 4 and the second coil 5, that is, the inter-coil low permeability layer 8 is too thin, Performance such as durability and reliability (element function in a broad sense) cannot be guaranteed. Therefore, the inventor conducted an analysis experiment in which the thickness of the inter-coil low permeability layer 8 is changed in various ways and the chip body 2 is pressure-bonded and laminated to ensure performance and reliability required as a multilayer electronic component. The lower limit value of the thickness of the inter-coil low magnetic permeability layer 8 that can be confirmed was confirmed. As a result, it was found that the thickness T1 of the inter-coil low magnetic permeability layer 8 needs to be 0.04 times or more of the entire thickness T2 of the magnetic body portion 7 (0.04 ≦ T1 / T2). .
Based on this knowledge, in the choke coil 1, as shown in FIG. 2, the total thickness T2 of the magnetic body portion 7 is set to 500 μm, and correspondingly, 0.04 ≦ T1 / T2 is satisfied. The thickness T1 of the low magnetic permeability layer 8 between the coils was set to 20 μm or more.

Further, the low magnetic permeability portion 6 and the magnetic body portion 7 are formed by laminating the low magnetic permeability material sheets 61-66, the ceramic sheets 71-75, 76-80, and the conductor patterns 41, 42, 51, 52 as described above. At this time, if the inter-coil low magnetic permeability layer 8 is too thick, cracks occur in the inter-coil low magnetic permeability layer 8 after crimping.
Therefore, the inventor conducted an experiment for variously changing the thickness of the inter-coil low permeability layer 8 as will be described later and crimping and laminating the chip body 2 so that the inter-coil low permeability layer 8 does not crack. The upper limit value of the thickness of the low permeability layer 8 between the coils was confirmed. As a result, it is necessary to make the thickness T1 of the inter-coil low permeability layer 8 equal to or less than 0.14 times the total thickness T2 of the magnetic body portion 7 (T1 / T2 ≦ 0.14). Got.
Based on such knowledge, the choke coil 1 has a low magnetic permeability between the coils so that the total thickness T2 of the magnetic body portion 7 is 500 μm, and correspondingly, T1 / T2 ≦ 0.14. The thickness T1 of the layer 8 was set to 70 μm or less. In this way, even if a strong pressing force is applied during the pressure-bonding lamination, particularly a stress that exceeds the criticality of failure is not generated in the low permeability portion 6 including the inter-coil low permeability layer 8. And the occurrence of cracks can be avoided.
In this way, the structural setting that regulates the upper limit of the thickness of the inter-coil low magnetic permeability layer 8 prevents cracks from occurring in the inter-coil low magnetic permeability layer 8 and provides a highly reliable choke coil. It can be realized.

  As described above, the inventor found that the ratio T1 / T2 between the total thickness T2 of the magnetic body portion 7 and the thickness T1 of the inter-coil low magnetic permeability layer 8, the presence / absence of cracks, and the problem in element function. An experiment was conducted to confirm the correlation with the presence or absence. The experiment and the knowledge obtained thereby will be described.

  FIG. 4 is a cross-sectional view schematically showing a press-bonding process performed using a hot press machine as a main process of the press-bonding experiment, FIG. 5 is a table showing the results of the press-bonding experiment, and FIG. FIG. 9 is a copy of a micrograph showing the internal state of the chip body obtained in the pressure lamination experiment. 6 to FIG. 9, the vicinity of one of the two cross-sections inside the chip main body 2 in which the square ring shape of the low magnetic permeability portion 6 is cut in a circle is enlarged and represented by a microscope. ing.

All the constituent materials as shown in FIG. 3 were laminated, and they were pressure-bonded while being heated by a hot press 10 as shown in FIG. The process conditions at this time, the heating temperature was 50 ° C. to 80 ° C., and the pressure and ^{450kgf / cm 2 ~500kgf / cm 2} .
In FIG. 4, only one choke coil 1 is shown for easy understanding.
As shown in FIG. 1, the overall external dimensions of the chip body 2 are W × L × T2 = 1000 × 1250 × 500 [μm], common to each sample, and the thickness of the low permeability layer 8 between the coils inside the chip body 2. A plurality of samples having a thickness T1 of 20, 50, 70, 80 [μm] were produced. And after carrying out the press-bonding lamination | stacking about each of those, the internal state was investigated by microscope photography etc.

As a result, when the thickness T1 of the low permeability layer 8 between the coils is 20 μm (FIG. 6), 50 μm (FIG. 7), and 70 μm (FIG. 8), no cracks are generated. There wasn't. However, when the thickness is 80 μm, as shown in FIG. 9, a large crack 15 extending across the entire width in the horizontal direction in the inter-coil low-permeability layer 8, which is substantially the center in the thickness direction of the low-permeability portion 6. And the remarkable crack 16 which runs from the right end of the low-permeability part 6 to a center part from a little upper direction generate | occur | produced.
Here, the setting of T1 = 80 μm corresponds to T1 / T2 = 0.16. A setting of T1 = 70 μm corresponds to T1 / T2 = 0.14.

  On the other hand, apart from the presence or absence of the occurrence of cracks, as shown in FIG. 5, the thickness of the inter-coil low permeability layer 8 is less than 20 μm, 20 μm, 50 μm, 70 μm, and 80 μm, respectively. We analyzed whether or not problems in device function such as withstand voltage characteristics and durability occur. As a result, in the case of 20 μm, 50 μm, 70 μm, and 80 μm, there is no problem in device function. However, when the thickness is less than 20 μm, sufficient withstand voltage characteristics and durability cannot be achieved. It has been found that such a problem in device function occurs. Here, the setting of T1 <20 μm corresponds to T1 / T2 <0.04.

  As a result of these experiments and analyses, as shown in FIG. 5, from the viewpoint of preventing the occurrence of cracks, the thickness of the low magnetic permeability layer 8 between the coils may be 70 μm or less and T1 / T2 ≦ 0.14. From the viewpoint of securing a sufficient element function, it has become clear that the thickness of the inter-coil low magnetic permeability layer 8 should be set to 20 μm or more to be T1 / T2. That is, it was found that by setting 0.04 ≦ T1 / T2 ≦ 0.14, it is possible to achieve both prevention of crack generation and securing sufficient element function.

Next, the generation factors of the cracks 15 and 16 in the chip body 2 at the time of pressure lamination are assumed based on the above experimental results.
FIG. 10 is a cross-sectional view schematically showing a mechanism for generating cracks in the chip body during pressure lamination. Here, for simplification of explanation and illustration, only the inner four sheets (ceramic sheets 74, 75, 76, 77) of the ten ceramic sheets 71 to 80 constituting the unsintered magnetic body portion 7 are used. And the six low-permeability material sheets 61 to 66 constituting the unsintered low-permeability portion 6 will be described below. Of course, in the case of using all of 71 to 80, the crack generation mechanism described here is basically the same.

As shown in FIG. 10A, the unsintered chip body 2 is in a state where all the sheets are laminated in a flat plate shape. The chip body in this state is set between the blocks 11 and 12 of the hot press machine as shown in FIG.
In the crimping lamination process, the chip body 2 is deformed by the pressing force P as shown in FIG. Due to this deformation, the ceramic sheets 74 to 77 flow into the hollow portions V1 and the gaps V2 on both sides of the unsintered low magnetic permeability portion 6. Thereby, the ceramic sheet 74-77 (namely, material of a magnetic body part) is filled into the hollow part V1 and the clearance gap V2. However, when such deformation occurs, peeling and cracking occur in the six low magnetic permeability material sheets 61 to 66.

That is, the unsintered ceramic sheets 74 to 77 and the low magnetic permeability material sheets 61 to 66 can be regarded as viscous fluids having extremely high viscosity. The ceramic sheets 74 to 77 are applied with a flat pressing force by the flat blocks 11 and 12. For this reason, when a pressing force is applied to the chip body 2 from the uncompressed state shown in FIG. 10A, the ceramic sheets 74 to 77, which are viscous fluids, are shown in FIG. 10B. In addition, flows Q1 to Q8 that flow into the hollow portion V1 and the gap V2 while avoiding the unsintered low magnetic permeability portion 6 are generated. Along with this, the ceramic sheets 74 to 77 in the upper and lower portions of the unsintered low magnetic permeability portion 6 become thinner.
At this time, the adhesiveness at the joint surface between the ceramic sheet 75 and the low magnetic permeability material sheet 61 and the adhesiveness at the joint surface between the ceramic sheet 76 and the low magnetic permeability material sheet 66 are lower. It is larger than the adhesiveness at the joint surface between ˜66. For this reason, the low magnetic permeability material sheet 61 and the low magnetic permeability material sheet 66 are dragged by the flows Q1, Q2, Q5, and Q6 of the ceramic sheets 75 and 76, respectively, and a large displacement in the lateral direction and the oblique direction occurs.
Then, due to the strong shear stress, bending stress, etc. (not shown) caused by the large displacement, the joint surfaces of the low magnetic permeability material sheets 61 to 66 are peeled off or cracked, which causes cracks. It will be understood that it will be 15. In addition, due to material variations and dimensional errors of the ceramic sheets 74 to 77 and the low permeability material sheets 61 to 66, there are variations in shear stress and bending stress generated in the low permeability material sheets 61 to 66. It is assumed that exfoliation and cracking at the joint surface are promoted.

  The shear stresses and bending stresses applied to the flows Q1 to Q8 accompanying the deformation of the ceramic sheets 74 to 77 and the low magnetic permeability material sheets 61 to 66 due to the deformation are caused by the unsintered low magnetic permeability portion 6. The larger the thickness, the larger. And since the unsintered low-permeability part 6 is comprised centering on the low-permeability material sheet 63 and the low-permeability material sheet 64 (that is, the sheet | seat which comprises the low-permeability layer 8 between coils), it is a coil. If the thickness of the low-permeability layer 8 is too large, the above cracks are generated.

  As described above, if the thickness of the inter-coil low magnetic permeability layer 8 is too thick, it is assumed that the crack 15 is generated. Therefore, it is necessary to adjust the thickness of the inter-coil low magnetic permeability layer 8 as in the choke coil 1 of this embodiment. Such adjustment of the thickness of the low magnetic permeability layer 8 between the coils may be performed by changing the thickness of the low magnetic permeability material sheet 63 and the low magnetic permeability material sheet 64, or the inter-coil low magnetic permeability layer 8 may be adjusted. You may make it carry out by changing the number of sheets of the low magnetic permeability material sheet to comprise.

In addition, this invention is not limited to the said Example, A various deformation | transformation and change are possible within the range of the summary of invention.
In the above embodiment, an example of a structure in which the low magnetic permeability portion 6 completely includes the first coil 4 and the second coil 5 has been described. For example, as shown in FIG. You may make it the structure exposed to the surface (namely, outer side) of the low magnetic permeability part 6. FIG.
In the above-described embodiment, the laminated common mode choke coil is lifted as an example of the laminated electronic component. However, the first coil 4 is a primary coil, and the second coil 5 is a secondary coil. Of course, the present invention can also be applied to the laminated transformer.

1 is an external view of a multilayer electronic component according to an embodiment of the present invention. It is arrow AA sectional drawing of FIG. FIG. 2 is an exploded perspective view of the multilayer electronic component of FIG. 1. It is sectional drawing which represented typically the crimping | compression-bonding lamination process performed using the hot press machine. It is the table | surface which represented the result of the crimping | compression-bonding experiment collectively. FIG. 5 is a photocopy of a micrograph showing the inside of a chip body when the thickness of a low magnetic permeability layer between coils is 20 μm. FIG. 4 is a photocopy of a micrograph showing the inside of a chip body when the thickness of a low magnetic permeability layer between coils is 50 μm. FIG. 4 is a photocopy of a micrograph showing the inside of a chip body when the thickness of a low magnetic permeability layer between coils is 70 μm. FIG. 4 is a photomicrograph showing the inside of a chip body when the thickness of a low magnetic permeability layer between coils is 80 μm. It is sectional drawing which represents typically the mechanism in which a crack generate | occur | produces. It is sectional drawing which shows the modification of this Example. It is sectional drawing showing the structure of the principal part of the conventional multilayer common mode choke coil.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Choke cor, 2 ... Chip body, 3-1 to 3-4 ... External terminal, 4 ... 1st coil, 5 ... 2nd coil, 6 ... Low magnetic permeability part, 7 ... Magnetic body part, 8 ... Low magnetic permeability layer between coils, 41, 42, 51, 52 ... Conductor pattern, 61-66 ... Low magnetic permeability material sheet, 62a, 65a ... Via hole, 71-80 ... Ceramic sheet, S1-S6 ... Square hole, V1 ... Hollow part.

Claims (7)

A first coil, a second coil disposed so as to have a winding axis aligned with the winding axis of the first coil, and spaced apart from each other, and the first and second coils A low permeability portion having a hollow portion formed by hollowing out a predetermined region including the winding axis inside the winding inside of the first and second coils, and containing the hollow portion A laminated electronic component comprising a magnetic body part that encloses the entire low magnetic permeability part,
The low-permeability portion includes an inter-coil low-permeability layer that is interposed between the first coil and the second coil and has a hole in the center, and a plurality of the first coil A low permeability layer interposed between the conductor pattern layers and having a hole in the center portion, and a low permeability layer interposed between the plurality of conductor pattern layers constituting the second coil and having a hole in the center portion. In a state where the magnetic layer is overlapped so as to form the hollow portion by communicating each hole in the central portion, the magnetic layer is pressure-bonded and laminated.
The magnetic body part is formed by pressing and laminating a magnetic material layer wider than the low magnetic permeability part from above and below the low magnetic permeability part,
The thickness of the low magnetic permeability layer between the coils is 0.04 times or more and 0.14 times or less of the total thickness of the magnetic body part,
A multilayer electronic component characterized by that. The multilayer electronic component according to claim 1,
The low magnetic permeability portion has a magnetic permeability of 1/10 or less of the magnetic permeability of the magnetic body portion.
A multilayer electronic component characterized by that. The multilayer electronic component according to claim 1,
The low magnetic permeability part has a magnetic permeability within a range of 1 or more and 10 or less.
A multilayer electronic component characterized by that. The multilayer electronic component according to claim 1,
The low magnetic permeability part is made of a nonmagnetic material having a magnetic permeability of about 1.
A multilayer electronic component characterized by that. The multilayer electronic component according to any one of claims 1 to 4,
The magnetic body portion is made of a magnetic body having a magnetic permeability of about 100.
A multilayer electronic component characterized by that. The multilayer electronic component according to claim 1,
The low magnetic permeability part is made of glass ceramics.
A multilayer electronic component characterized by that. The multilayer electronic component according to any one of claims 1 to 6,
The magnetic body portion is made of Ni-Cu-Zn ferrite.
A multilayer electronic component characterized by that.

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