JP2005116647A - Common mode choke coil, manufacturing method thereof, and common mode choke coil array - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase a self-resonance frequency of a common mode coil by making large an interval between a leadout electrode and a coil conductor. <P>SOLUTION: The common mode choke coil has a structure that a first leadout electrode layer 3, a first coil conductor layer 5, a second coil conductor layer 7, and a second leadout electrode layer 9 are sequentially formed via the interlayer insulating layers 4, 6 and 8. The first leadout electrode layer 3 and the second coil conductor layer 7 are electrically connected. The first coil conductor layer 5 and the second leadout electrode layer 9 are electrically connected. Pairs of these leadout electrode layers and the coil conductor layer are electrically insulated with each other. Moreover, the electrode layers and the coil conductor layers are sandwiched by the first and second magnetic substrates 1, 12. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a common mode choke coil, a manufacturing method thereof, and a common mode choke coil array, and more particularly to a filter used for suppressing a common mode current causing electromagnetic interference which is a problem in a balanced transmission system, and a manufacturing method thereof. Regarding the method.

  Conventionally, a laminated type is known as a chip-type common mode choke coil. This component has a structure in which a coil conductor pattern is formed on the surface of a magnetic material sheet such as ferrite and a first coil magnetic sheet forming a first coil and a similar second coil magnetic sheet are alternately laminated.

  Further, a common mode choke coil disclosed in Patent Document 1 below is known as one using a thin film construction method. In this component, a lead electrode is formed on a magnetic substrate by a thin film method, and then an insulating layer, a first coil conductor, an insulating layer, a second coil conductor, and an insulating layer are sequentially formed using a thin film method, and the magnetic layer is formed from the upper surface. The structure is sandwiched between substrates.

  Moreover, in the common mode choke coil by the thin film method, as shown in Patent Document 2 below, the central part and the outer peripheral part of the insulating layer of the thin film method are etched in order to improve the magnetic coupling between the coils and increase the common impedance. In some cases, a closed magnetic circuit structure is formed by bonding (developing) the upper magnetic substrate with a resin obtained by mixing magnetic powder with an insulating material. Patent Document 3 below also discloses a closed magnetic circuit configuration.

JP-A-8-203737 Japanese Patent Laid-Open No. 11-54326 JP 2003-133135 A

  In the common mode choke coils of Patent Document 1, Patent Document 2, and Patent Document 3 described above, at least a pair of coils, the extraction electrode and the coil conductor that are electrically connected face each other at a close distance with a single insulating layer interposed therebetween. Therefore, a large capacitance component is generated in this portion, and the (common mode) self-resonance frequency (SRF) of the common mode choke coil is lowered.

  As a countermeasure, it may be possible to increase the thickness of the insulating layer between the extraction electrode and the coil conductor. In this case, however, it may be difficult to remove the insulating layer for the contact (form a through hole or via hole). It is done. Further, the distance in the thickness direction between the first magnetic substrate and the second magnetic substrate is increased, leading to a decrease in impedance.

  In view of the above points, the present invention provides a common mode choke coil that can increase the (common mode) self-resonance frequency of the common mode coil by increasing the interval between the extraction electrode and the coil conductor, and a method of manufacturing the same. An object is to provide a common mode choke coil array.

  Other objects and novel features of the present invention will be clarified in embodiments described later.

In order to achieve the above object, a common mode choke coil according to the invention of claim 1 includes a first extraction electrode layer, a first coil conductor layer, a second coil conductor layer, and a second extraction electrode layer. It has a configuration in which films are sequentially formed through insulating layers between layers,
The first lead electrode layer and the second coil conductor layer are electrically connected, and the first coil conductor layer and the second lead electrode layer are electrically connected, and their lead The electrode layer and coil conductor layer pair are electrically insulated from each other.

  A common mode choke coil according to a second aspect of the present invention is the common mode choke coil according to the first aspect, wherein the first lead electrode layer, the first coil conductor layer, the second coil conductor layer, and the second lead electrode layer are magnetic substrates. It is characterized by being placed in between.

  A common mode choke coil according to a third aspect of the present invention is the common mode choke coil according to the first or second aspect, wherein each insulating layer is either a central region surrounded by a coil pattern of the coil conductor layer or an outer peripheral region of the coil pattern. Or it is removed by both, The magnetic material is provided in the removal part, It is characterized by the above-mentioned.

  A common mode choke coil according to a fourth aspect of the present invention is the common mode choke coil according to the second aspect, wherein an insulating layer between one magnetic substrate and the first lead electrode layer is formed over the entire main surface of the one magnetic substrate. Each insulating layer excluding the impedance value adjusting insulating layer is removed in one or both of the central region surrounded by the coil pattern of the coil conductor layer and the outer peripheral region of the coil pattern. The magnetic material is provided in the removed portion.

  A common mode choke coil according to a fifth aspect of the present invention is the common mode choke coil according to the first, second, third, or fourth aspect, wherein the first lead electrode layer and the second coil conductor layer are connected to each other by the first mode. A first connecting intermediate conductor layer is formed in the same layer as the coil conductor layer, and the same layer as the second coil conductor layer for connecting the first coil conductor layer and the second lead electrode layer. The second connecting intermediate conductor layer is formed.

  The common mode choke coil array according to the invention of claim 6 includes a plurality of the common mode choke coils of claim 1, 2, 3, 4 or 5.

According to a seventh aspect of the present invention, there is provided a method for manufacturing a common mode choke coil, wherein the first extraction electrode layer, the first coil conductor layer, the second coil conductor layer, and the second extraction electrode layer are provided with an insulating layer between the layers. When sequentially forming a film through
The lead electrode layer and the coil conductor layer are formed by a plating method, the first lead electrode layer and the second coil conductor layer are electrically connected, and the first coil conductor layer and the first coil conductor layer are electrically connected. The second extraction electrode layer is electrically connected.

  A method for manufacturing a common mode choke coil according to an eighth aspect of the present invention is the method for manufacturing a common mode choke coil according to the seventh aspect, wherein the first lead electrode layer, the first coil conductor layer, and the second coil conductor layer are formed on the first magnetic substrate. In addition, the second lead electrode layer is sequentially formed through an interlayer insulating layer, and then the second magnetic substrate is bonded through an adhesive layer.

  The method for manufacturing a common mode choke coil according to the invention of claim 9 is the method according to claim 7 or 8, wherein each insulating layer has a central region surrounded by a coil pattern of the coil conductor layer or an outer peripheral region of the coil pattern. One or both of them are removed by etching, and a magnetic powder-containing resin is embedded as a magnetic material in the removed portion.

  According to a tenth aspect of the present invention, there is provided a method for manufacturing a common mode choke coil according to the eighth aspect, wherein the first magnetic substrate and the first extraction electrode layer are used as an insulation layer for adjusting an impedance value. The central region surrounded by the coil pattern of the coil conductor layer or the outer peripheral region of the coil pattern in each insulating layer excluding the impedance value adjusting insulating layer is formed on the entire main surface of the magnetic substrate. One or both of them are removed by etching, and a magnetic powder-containing resin is embedded as a magnetic material in the removed portion.

  According to the present invention, when the first lead electrode layer, the first coil conductor layer, the second coil conductor layer, and the second lead electrode layer are sequentially formed through the insulating layers between the layers, The first extraction electrode layer and the second coil conductor layer are electrically connected to electrically connect the first coil, and the first coil conductor layer and the second extraction electrode layer are electrically connected to each other. Since the second coil is connected to form a pair of magnetically coupled coils, the distance between the extraction electrode layer and the coil conductor layer can be easily increased without increasing the number of manufacturing steps. The capacity between the two can be reduced. As a result, it is possible to increase the self-resonance frequency, increase the common impedance in the high frequency band, and improve the removal effect of the high frequency noise component.

  Hereinafter, as a best mode for carrying out the present invention, embodiments of a common mode choke coil, a manufacturing method thereof, and a common mode choke coil array will be described with reference to the drawings.

  1 to 3 show a first embodiment of the present invention. FIG. 1 is an exploded perspective view of a chip type common mode choke coil, FIG. 2 is an enlarged exploded perspective view of a main part, and FIG. 3 is a manufacturing process. It is explanatory drawing which shows. In actual fabrication, a plurality of components are fabricated on the substrate at the same time. In this embodiment, description will be made for one element.

  As shown in these drawings, in the chip type common mode choke coil, the insulating layer 2 is formed on the main surface of the first magnetic substrate 1, and the first lead electrode layer 3, the insulating layer 4, the first A coil conductor layer (spiral coil conductor pattern) 5, an insulating layer 6, a second coil conductor layer (spiral coil conductor pattern) 7, an insulating layer 8, a second extraction electrode layer 9, and an insulating layer 10 are sequentially formed. Further, the adhesive layer 11 and the second magnetic substrate 12 are laminated and integrated in this order.

  For the purpose of increasing the impedance, as shown in the figure, one or both of the central region surrounded by the coil pattern of each insulating layer 2, 4, 6, 8, 10 and the outer peripheral region of the coil pattern are removed. One or both of the insulating layer removing portions 21 and 22 are formed, and the magnetic material 13 is embedded in the insulating layer removing portions 21 and 22 as shown in FIG. 3 showing the manufacturing process, and the adhesive layer 11 is interposed on the magnetic material 13. It is also effective to bond the second magnetic substrate 12.

  When the insulating layer and the electrode layer or the conductor layer are alternately laminated, the first lead electrode layer 3 and the second coil conductor layer 7 are electrically connected via the contact holes 4a and 6a formed in the insulating layers 4 and 6. Connected. Further, as shown in the enlarged exploded perspective view of the main part of FIG. 2, in order to ensure the electrical connection between the first extraction electrode layer 3 and the second coil conductor layer 7 by jumping over the first coil conductor layer 5, If the intermediate conductor layer 5a for connection is formed at the same time (in the same layer) when the one-coil conductor layer 5 is formed, the electrical connection is further ensured. That is, the first lead electrode layer 3 is connected to the second coil conductor layer 7 through a route of the contact hole 4a, the connecting intermediate conductor layer 5a, and the contact hole 6a.

  Similarly, the second lead electrode layer 9 and the first coil conductor layer 5 are electrically connected via contact holes 6b and 8b formed in the insulating layers 6 and 8, respectively. At the same time as forming the coil pattern of the second coil conductor layer 7 in order to jump over the second coil conductor layer 7 and ensure the electrical connection between the second lead electrode layer 9 and the first coil conductor layer 5. If the connection intermediate conductor layer 7b is formed (in the same layer), the electrical connection is further ensured. That is, the first coil conductor layer 5 is connected to the second lead electrode layer 9 through the path of the contact hole 6b, the connecting intermediate conductor layer 7b, and the contact hole 8b.

  One end of each extraction electrode layer and one end of each coil conductor layer are connected to external electrodes (formed on the outer peripheral surface of the chip), respectively.

  The magnetic substrates 1 and 12 are sintered ferrite, composite ferrite, etc., and the insulating layers 2, 4, 6, 8, and 10 are materials having excellent insulating properties such as polyimide resin and epoxy resin, and good workability. The magnetic powder-containing resin constituting the material 13 is obtained by mixing magnetic powder such as ferrite in an epoxy resin, a polyimide resin or the like.

  The manufacturing procedure of the chip-type common mode choke coil is as follows. However, this is a case where the extraction electrode layers 3 and 9 and the first and second coil conductor layers 5 and 7 which are spiral coil conductor patterns are formed by a vacuum film formation method (evaporation, sputtering, etc.) or a plating method.

  An insulating layer 2 is formed on the magnetic substrate 1. As a forming method, a spin coating method, a dip method, a spray method, or a printing method is employed.

  A metal film is formed on the insulating layer using a vacuum film formation method or a plating method. The metal used is preferably Cu, Al or the like in terms of conductivity and workability. Thereafter, a pattern is formed to form the first extraction electrode layer 3. The patterning method is performed by an etching method using photolithography, an additive method (plating) using photolithography, or the like.

  Next, an insulating layer 4 made of an insulating resin is formed. The construction method is the same as that of the insulating layer 2, but at this time, a contact hole 4a for connecting the first extraction electrode layer 3 and the second coil conductor layer 7 is formed.

  Next, the first coil conductor layer 5 which is a spiral coil conductor pattern is formed. The construction method is the same as that of the first extraction electrode layer 3. If the plating method is used, it is easy to reduce the pitch of the conductor, and it is possible to cope with downsizing and the like.

  Further, for the connection between the first extraction electrode 3 and the second coil conductor layer 7 which need to be connected over the first coil conductor layer 5, as shown in the enlarged exploded perspective view of the main part of FIG. If the connecting intermediate conductor layer 5a is formed at the same time when the spiral coil conductor pattern of the conductor layer 5 is formed, the electrical connection becomes easier and more reliable.

  Next, an insulating layer 6 made of an insulating resin is formed. The construction method is the same as that of the insulating layer 4. At this time, a connection contact hole 6a for connecting the first extraction electrode layer 3 and the second coil conductor layer 7 and a connection for connecting the first coil conductor layer 5 and the second extraction electrode layer 9 are used. Contact holes 6b are respectively formed.

  In the same manner, the second coil conductor layer 7, the insulating layer 8 (insulating resin), the extraction electrode layer 9, and the insulating layer 10 (insulating resin), which are spiral coil conductor patterns, are sequentially formed.

  When the spiral coil conductor pattern of the second coil conductor layer 7 is formed, if the intermediate conductor layer 7b for connection is formed at the same time for connecting the first coil conductor layer 5 and the second lead electrode layer 9, the electrical connection is further improved. Easy and reliable.

  Thus, after performing the film-forming process which forms alternately the insulating layer which consists of insulating resin, and the conductor layer containing a spiral coil conductor pattern on the 1st magnetic board | substrate 1, an adhesive agent is apply | coated and the adhesive layer 11 is applied. And the second magnetic substrate 12 is attached.

  In order to increase the impedance, either one or both of the central region surrounded by the coil pattern of each insulating layer 2, 4, 6, 8, 10 and the outer peripheral region of the coil pattern is removed, and the insulating layer removing unit 21, In the case of forming one or both of the insulating layers 22, each insulating layer is formed together with a film forming step of alternately forming an insulating layer made of an insulating resin and a conductor layer including a spiral coil conductor pattern on the first magnetic substrate 1. 3A is performed by performing an etching process for removing the insulating layer portion in the central region surrounded by the coil conductor pattern and the outer peripheral region of the coil conductor pattern (usually etching is performed for each insulating layer). Thus, a laminated body 20 in which coil conductor patterns (first and second coil conductor layers 5 and 7) are built on the first magnetic substrate 1 is obtained, and the central region and the outer peripheral region of the laminated body 20 are obtained. Insulating layer was removed insulating layer removing portion 21 (recess) and an insulating layer removing section 22 (cutout part) is to be formed.

  Next, from the upper surface of the insulating layer 10 (upper surface of the laminated body 20 in FIG. 3), a magnetic powder-containing resin (cured to become the magnetic layer 13) is printed in the application step of FIG. 3B, and then cured. . At the time of printing and coating, the insulating layer removing portions 21 and 22 are coated so as to embed a resin containing magnetic powder as the magnetic material 13, and after curing, they are polished to the position of the dotted line P and flattened. Thereafter, in the bonding step of FIG. 3C, an adhesive is applied to the planarized magnetic material 13 to provide the adhesive layer 11 and the second magnetic substrate 12 is attached.

  The above description is for one element, but in actuality, a plurality of elements are manufactured on the substrate simultaneously. After the one fabricated on this substrate is cut into a one-element chip, external electrodes are formed on the outer surface of the chip, and a common mode choke coil is completed.

  The reason why the self-resonant frequency (SRF) can be increased in the case of the present embodiment will be described with reference to FIG.

The self-resonant frequency f ₀ of the coil (including the common mode choke coil) can be simply expressed by the following equation.
f ₀ = 1 / {2π (LC) ^1/2 } (1)
(However, L: Coil inductance, C: (Floating) capacitance generated in the coil)

In order to increase the self-resonance frequency, it is necessary to reduce L and C. However, L is a value that determines the common mode impedance and cannot be changed. On the other hand, C is a stray capacitance component and is ideally reduced. The C component (C1) between the extraction electrode layers 3 and 9 and the coil conductor layers 5 and 7 has the greatest influence on the C component in terms of structure. Therefore, it is important to reduce the C1 component in order to improve the self-resonant frequency. The capacity C is generally C = εS / d (2)
(Where ε: dielectric constant (fixed by material), S: area of opposing conductor, d: distance of opposing conductor)
It is represented by ε is a fixed value depending on the material and is difficult to adjust. Ideally, S should be made small, but it is also possible to influence the limit on fabrication and other characteristics. Increasing d can be realized by improvement according to the present embodiment.

  That is, in the conventional example of FIG. 4A, the first extraction electrode layer 3 and the first coil conductor layer 5 are connected to form one coil, and the second extraction electrode layer 9 and the second coil conductor layer 7 are formed. To the other coil (however, 4, 6 and 8 are insulating layers) and the C component (C1) between the extraction electrode layer and the coil conductor layer because the distance between the extraction electrode layer and the coil conductor layer is small. 4B, in the present embodiment, the first extraction electrode layer 3 and the second coil conductor layer 7 are connected to form one coil, and the second extraction electrode layer 9 and the first The coil conductor layer 5 is connected to form the other coil, and the C component (C1) in the formula (2) can be reduced by increasing the distance d between the extraction electrode layer and the coil conductor layer in the same coil. . Therefore, since C in the equation (1) becomes small, it is possible to increase the self-resonance frequency. As a result, a difference occurs in a high frequency band even with a low frequency and an equivalent impedance. That is, the configuration of the present embodiment in FIG. 4B improves the noise removal effect in a higher frequency band than the conventional example in FIG.

  FIG. 5 shows the frequency characteristics (improvement estimated value) of the impedance in the case of this embodiment of FIG. 4B with respect to the conventional example of FIG. As can be seen from FIG. 5, characteristics are improved in a frequency range higher than about 300 MHz.

  According to the first embodiment, the following effects can be obtained.

(1) The first extraction electrode layer 3 and the second coil conductor layer 7 constitute a first coil, and the second extraction electrode layer 9 and the first coil conductor layer 5 constitute a second coil. A common mode choke coil is formed by these coils having mechanical coupling. In this case, as shown in FIG. 4B, by increasing the distance between the extraction electrode layer and the coil conductor layer in each coil, the self-resonance frequency of the common mode choke coil can be increased by reducing the stray capacitance. As a result, it is possible to increase the common mode impedance in the high frequency band and improve the removal effect of the high frequency noise component.

(2) In each insulating layer 2, 4, 6, 8, 10, remove either one or both of the central region surrounded by the coil pattern of the coil conductor layers 5, 7 and the outer peripheral region of the coil pattern, When the magnetic material 13 is provided in the insulating layer removing portion 21 (recessed portion) and the insulating layer removing portion 22 (notched portion), the magnetic material 13 is substantially closed by the first and second magnetic substrates 1 and 12 and the magnetic material 13. Impedance can be increased as a path.

  FIG. 6 is a second embodiment of the present invention and shows an example in which a common mode choke coil array is manufactured. In this case, a plurality (two in the illustrated case) of the common mode choke coils of the first embodiment are arranged side by side on the first magnetic substrate 1. The same or corresponding parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  7 and 8 show the configuration of the common mode choke coil according to the third embodiment of the present invention, which can easily adjust the impedance value. In this case, the impedance value adjusting insulating layer 2A is provided on the entire main surface of the first magnetic substrate 1, and the first extraction electrode layer 3, the insulating layer 4, the first coil conductor layer (spiral coil conductor pattern) is formed thereon. ) 5, the insulating layer 6, the second coil conductor layer (spiral coil conductor pattern) 7, the insulating layer 8, the second lead electrode layer 9, and the insulating layer 10 are sequentially formed. Then, either one or both of the central region surrounded by the coil pattern of each insulating layer 2, 4, 6, 8, 10 and the outer peripheral region of the coil pattern is removed, or one of the insulating layer removing portions 21, 22 or Both are formed, and the magnetic material 13 (magnetic powder-containing resin) is embedded in the insulating layer removal portions 21 and 22 as shown in FIG. Thereafter, the second magnetic substrate 12 is bonded and integrated on the magnetic material 13 via the adhesive layer 11.

  Other configurations are the same as those of the first embodiment described above, and the same or corresponding parts are denoted by the same reference numerals and description thereof is omitted.

  According to the third embodiment, the impedance value adjusting insulating layer 2A formed on the entire main surface of the first magnetic substrate 1 includes the first magnetic substrate 1 and the magnetic material 13 as shown in FIG. The impedance value (especially the common mode impedance value) can be adjusted by changing the thickness of the insulating layer 2A for adjusting the impedance value.

Although the embodiments of the present invention have been described above, it will be obvious to those skilled in the art that the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims.

It is Embodiment 1 of this invention, and is an exploded perspective view in the case of comprising a common mode choke coil. FIG. 3 is an enlarged exploded perspective view of a main part of the first embodiment. FIG. 6 is an explanatory diagram showing a manufacturing process in the case of the first embodiment. The distance between the extraction electrode layer and the coil conductor layer in the conventional example and the first embodiment is shown in comparison, (A) is an exploded perspective view of the conventional example, and (B) is an exploded perspective view in the case of the first embodiment. . It is a graph which shows the frequency characteristic of the impedance in the case of a prior art example and Embodiment 1. FIG. It is Embodiment 2 of this invention, and is an exploded perspective view in the case of comprising a common mode choke coil array. It is a disassembled perspective view in the case of comprising the common mode choke coil which is Embodiment 3 of this invention and has an impedance value adjustment function. FIG.

Explanation of symbols

1,12 Magnetic substrate 2,2A, 4,6,8,10 Insulating layer 3,9 Lead electrode layer 4a, 6a, 6b, 8b
5,7 Coil conductor layer 5a, 7b Connection intermediate conductor layer 12 Adhesive layer 13 Magnetic material 20 Laminate 21 and 22 Insulating layer removing portion

Claims (10)

A common mode choke coil in which a first lead electrode layer, a first coil conductor layer, a second coil conductor layer, and a second lead electrode layer are sequentially formed through an interlayer insulating layer,
The first lead electrode layer and the second coil conductor layer are electrically connected, and the first coil conductor layer and the second lead electrode layer are electrically connected, and their lead A common mode choke coil, wherein a pair of an electrode layer and a coil conductor layer is electrically insulated from each other.   The common mode choke coil according to claim 1, wherein the first lead electrode layer, the first coil conductor layer, the second coil conductor layer, and the second lead electrode layer are disposed between the magnetic substrates.   The insulating layer is removed in either one or both of a central region surrounded by a coil pattern of the coil conductor layer and an outer peripheral region of the coil pattern, and a magnetic material is provided in the removed portion. 2. The common mode choke coil according to 2.   An insulating layer between one magnetic substrate and the first lead electrode layer is formed on the entire main surface of the one magnetic substrate to form an impedance value adjusting insulating layer, and each insulating layer excluding the impedance value adjusting insulating layer. The common layer according to claim 2, wherein the layer is removed at one or both of a central region surrounded by a coil pattern of the coil conductor layer and an outer peripheral region of the coil pattern, and a magnetic material is provided in the removed portion. Mode choke coil.   In order to connect the first lead electrode layer and the second coil conductor layer, a first connecting intermediate conductor layer is formed in the same layer as the first coil conductor layer, and the first coil conductor is formed. 5. The common mode according to claim 1, wherein a second connecting intermediate conductor layer is formed in the same layer as the second coil conductor layer in order to connect the layer and the second lead electrode layer. choke coil.   6. A common mode choke coil array including a plurality of common mode choke coils according to claim 1, 2, 3, 4, or 5. A method for producing a common mode choke coil in which a first extraction electrode layer, a first coil conductor layer, a second coil conductor layer, and a second extraction electrode layer are sequentially formed through an insulating layer between layers,
The lead electrode layer and the coil conductor layer are formed by a plating method, the first lead electrode layer and the second coil conductor layer are electrically connected, and the first coil conductor layer and the first coil conductor layer are electrically connected. A method of manufacturing a common mode choke coil, comprising electrically connecting two lead electrode layers.   The first lead electrode layer, the first coil conductor layer, the second coil conductor layer, and the second lead electrode layer are sequentially formed on the first magnetic substrate via an interlayer insulating layer, and then an adhesive layer The method for manufacturing a common mode choke coil according to claim 7, wherein the second magnetic substrate is bonded via the step.   In each insulating layer, one or both of the central region surrounded by the coil pattern of the coil conductor layer and the outer peripheral region of the coil pattern is removed by etching, and a magnetic powder-containing resin is embedded as a magnetic material in the removed portion A method for manufacturing a common mode choke coil according to claim 7 or 8.   An insulating layer between the first magnetic substrate and the first lead electrode layer is formed as an impedance value adjusting insulating layer on the entire main surface of the first magnetic substrate, and the impedance value adjusting insulating layer is formed. Either one or both of the central region surrounded by the coil pattern of the coil conductor layer and the outer peripheral region of the coil pattern is removed by etching in each insulating layer except the magnetic powder-containing resin as a magnetic material in the removed portion. The method for manufacturing a common mode choke coil according to claim 8, which is embedded.

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