JPWO2006008878A1 - Coil parts - Google Patents

Abstract

In the technologies described in the conventional patent documents 1 and 2, it is difficult to change the capacitance that defines the size of the characteristic impedance while securing the desired common mode impedance and normal mode impedance, and it is difficult to adjust the characteristic impedance. . The coil component 10 of the present invention is formed with a pair of upper and lower magnetic substrates 11 and 12, a nonmagnetic layer 13 interposed therebetween, and is spaced apart in the vertical direction within the nonmagnetic layer 13 and faces each other. And the first and second coil electrodes 14 and 15, and the first and second coil electrodes 14 and 15 have spiral first and second pattern electrodes, respectively. The first pattern electrodes 141A and 151A of the second coil electrodes 14 and 15 are respectively arranged on the innermost side in the vertical direction so as to be opposed to each other, and the areas of the first pattern electrodes 141A and 151A are arranged on the outer sides thereof. It is smaller than the area of the other second pattern electrodes 141B and 151B.

Description

  The present invention relates to a coil component, and more particularly to a coil component that can be suitably used as, for example, a common mode choke coil.

  For example, Patent Document 1 proposes a coil component that can be used as a common mode choke coil or the like. This coil component is a common mode choke coil including a nonmagnetic layer sandwiched between upper and lower magnetic substrates and a pair of coil electrodes formed in the nonmagnetic layer. The pair of coil electrodes are disposed to face each other in the thickness direction with an insulating layer interposed therebetween. Each coil electrode is composed of two layers of parallel spiral electrodes. The spiral electrode can efficiently obtain a large common mode impedance, and a high degree of coupling can be obtained by concentrating magnetic flux. Therefore, the common mode choke coil having such a configuration can obtain a large common mode impedance and a high coupling between the coils, so that the normal mode impedance can be kept low. Furthermore, since each coil is composed of two layers of parallel spiral electrodes, the cross-sectional area of the electrodes can be doubled compared to a single-layer electrode, and the DC resistance of the coil can be kept low.

  Patent Document 2 proposes a common mode choke coil for suppressing electromagnetic interference radiated mainly from a digital circuit having a high-speed signal transmission system. This common mode choke coil is characterized by a differential inductance and capacitance in a minute section of a balanced line, in which an electrode pattern consisting of a pair of meander-shaped parallel plate electrodes is placed opposite to each other through an insulating layer in a magnetic circuit including a magnetic core. Adjust the impedance.

JP 2003-133135 A JP 2000-277335 A

  However, the conventional coil component described in Patent Document 1 has the following problems. That is, when it is necessary to reduce the capacitance between the coils in order to obtain a desired characteristic impedance, it is necessary to narrow the opposing coil wire width or increase the distance between the coils. However, narrowing the coil wire width is not preferable because the DC resistance increases, and widening the distance between the coils widens the distance between the magnetic substrates, reducing the impedance acquisition efficiency and reducing the coupling degree. To do. Conversely, when it is necessary to increase the capacitance between the coils in order to obtain a desired characteristic impedance, it is necessary to increase the width of the opposing coil lines or to reduce the distance between the coils. However, increasing the coil wire width does not provide the required inductance because the space is limited, and it is difficult to ensure insulation between the magnetic substrates simply by reducing the distance between the coils. There is a limit in terms of.

  On the other hand, the conventional common mode choke coil described in Patent Document 2 has the following problems. That is, by arranging the meander-shaped parallel plate electrodes facing each other at a predetermined interval, uniform characteristic impedance can be obtained. On the other hand, the meander shape cannot obtain large impedance efficiently, and high coupling cannot be obtained. Impedance increases, which is not preferable. Furthermore, if a desired characteristic impedance is to be obtained, there is a problem similar to that in the technique of Patent Document 1 when adjusting the capacitance between the coils.

  The present invention has been made to solve the above problems, and can promote downsizing and low profile, wide range of acquired impedance with low resistance, and increase coupling between coils, In addition, an object of the present invention is to provide a coil component that can increase the degree of freedom in designing characteristic impedance.

  The coil component according to claim 1 of the present invention includes a pair of upper and lower magnetic substrates, a nonmagnetic layer interposed between these magnetic substrates, and a vertical separation within the nonmagnetic layer. A coil component comprising a pair of first and second coil electrodes formed and arranged opposite to each other, wherein the first and second coil electrodes are each at least two layers of spirals spaced apart from each other. Each of the first and second coil electrodes is disposed on the innermost side in the vertical direction and is opposed to each other, and each of the first pattern electrodes The area is larger or smaller than the second pattern electrodes arranged on the outer sides of the respective areas.

  The coil component according to claim 2 of the present invention is characterized in that, in the invention according to claim 1, each of the first and second coil electrodes has two layers of spiral pattern electrodes. To do.

  According to a third aspect of the present invention, in the coil component according to the first or second aspect, the line width of the first pattern electrode is different from the line width of the second pattern electrode. It is a feature.

  The coil component according to claim 4 of the present invention is the invention according to any one of claims 1 to 3, wherein the number of turns of the coil of the first pattern electrode is the number of turns of the second pattern electrode. The number of turns of the coil is different.

  According to the first to fourth aspects of the present invention, it is possible to promote downsizing and reduction in height, to increase the range of acquired impedance with low resistance, and to enhance the coupling between coils. In addition, it is possible to provide a coil component that can increase the degree of freedom in designing characteristic impedance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment of the coil components of this invention, (a) is a perspective view which shows the external appearance, (b) is sectional drawing of the BB line direction of (a). It is a figure which takes out and shows the coil electrode of the coil components shown in FIG. 1, (a) is a top view which shows the 1st, 2nd pattern electrode, (b) is an explanation which shows the connection state of the 1st, 2nd pattern electrode FIG. It is a disassembled perspective view which decomposes | disassembles and shows the coil components shown in FIG. It is a disassembled perspective view which shows other embodiment of the coil components of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Coil components 11, 12 Magnetic substrate 13 Nonmagnetic layer 14 1st coil electrode 15 2nd coil electrode 141A, 151A 1st pattern electrode 141B, 151B 2nd pattern electrode

  Hereinafter, the present invention will be described based on the embodiment shown in FIGS.

  For example, as shown in FIGS. 1 to 3, the coil component 10 of the present embodiment includes upper and lower magnetic substrates 11 and 12, and a plurality of insulating layers 13 </ b> A and 13 </ b> B interposed between the magnetic substrates 11 and 12. A pair of first and second coil electrodes 14 and 15 having a spiral planar shape disposed in the nonmagnetic layer 13 so as to face each other in the vertical direction, Two pairs of first and second external electrodes 16A, 16B, 17A, and 17B that are electrically connected to both ends of the coil electrodes 14 and 15, respectively, and are used as, for example, a common mode choke coil It is configured. In addition, an adhesive layer 18 is provided between the upper magnetic substrate 12 and the nonmagnetic layer 13 to bond them together.

  Usually, a plurality of coil components 10 can be simultaneously formed on a mother substrate. Internal wirings such as the first and second coil electrodes 14 and 15 can be formed by a photolithography technique or the like. Hereinafter, the coil component body including the upper and lower magnetic substrates 11 and 12, the nonmagnetic layer 13, and the first and second coil electrodes 14 and 15 will be referred to as a coil component body 10A as necessary.

  The magnetic substrates 11 and 12 are not particularly limited as long as they are made of a magnetic material. As the magnetic material, for example, a ferrite material excellent in high frequency characteristics is preferably used. In order to form the insulating layer 13 on the magnetic substrates 11 and 12, it is preferable that the bonding surface is polished to a surface roughness Ra of 0.5 μm or less.

  The nonmagnetic material layer 13 is formed by laminating a plurality of insulating layers 13A and 13B. As shown in FIG. 3, the third and fourth insulating layers 13B from the top of the nonmagnetic layer 13 are interposed between the first coil electrode 14 and the second coil electrode 15, and the coil component 10. This is a layer for setting the characteristic impedance. A method for forming these insulating layers 13A and 13B is not particularly limited, and for example, a spin coating method or the like can be used.

The insulating layers 13A and 13B are not particularly limited as long as they are formed of a nonmagnetic insulating material. Examples of the insulating material include thermosetting resins such as polyimide resin, epoxy resin, and benzocyclobutene resin, Glass such as SiO ₂ and glass ceramic are preferably used. Moreover, as an insulating material, the photosensitive resin material which provided photosensitivity as needed can also be used individually or in combination with said each material. The insulating layers 13A and 13B made of a photosensitive resin material are used when via holes are formed in the insulating layers 13A and 13B. When forming via holes, the insulating layers 13A and 13B are masked with a photomask, and then the insulating layers 13A and 13B are exposed and developed to form via holes. The thickness of the insulating layer 13A is preferably, for example, in the range of 1 to 3 μm, and the thickness of the insulating layer 13B is preferably in the range of 5 to 30 μm because of defining the characteristic impedance. As the adhesive used for the adhesive layer 18, a thermosetting resin such as a polyimide resin can be used.

  As shown in FIGS. 1 and 3, the first and second coil electrodes 14 and 15 are arranged to face each other so as to be symmetrical with each other in the vertical direction, and have a positional relationship overlapping each other. As will be described later, each of the coil electrodes 14 and 15 has first and second pattern electrodes formed in spiral shapes having substantially the same size, and the first and second pattern electrodes respectively have respective lead electrodes. To the first external electrodes 16A and 16B and the second external electrodes 17A and 17B (see FIG. 1A). Since the first and second coil electrodes 14 and 15 are each formed in a spiral shape, a wide range of impedance can be obtained, and the coil component 10 can be reduced in size and height.

  The first pattern electrodes of the first and second coil electrodes 14 and 15 are arranged to face each other with an insulating layer 13B having a thickness of 5 to 30 μm, and are different from the second pattern electrodes arranged on the outer sides thereof. It has an area. In the coil component 10, the capacitance between the first and second coil electrodes 14, 15 is adjusted according to the size of the area of the first pattern electrodes facing each other of the first and second coil electrodes 14, 15, and the common mode impedance The characteristic impedance is adjusted without incurring a decrease in coupling or a decrease in coupling degree. That is, in the present invention, the characteristic impedance of the coil component 10 can be set high by making the area of the first pattern electrode of each of the first and second coil electrodes 14 and 15 smaller than the area of the second pattern electrode. Conversely, the characteristic impedance of the coil component 10 can be set low by making the area of the upper and lower first pattern electrodes larger than the area of the second pattern electrodes.

  Hereinafter, the coil structure of the first and second coil electrodes 14 and 15 will be described in detail. The first and second coil electrodes 14 and 15 have substantially the same structure except that the first and second coil electrodes 14 and 15 have a vertically symmetrical structure in which only the size relationship of the areas of the first and second pattern electrodes is reversed upside down. The first coil electrode 14 will be mainly described.

  As shown in FIGS. 1B to 3, the first coil electrode 14 is located above the second coil electrode 15 with the insulating layer 13 </ b> B interposed therebetween. As shown in FIG. 3, the first coil electrode 14 includes two layers of spiral first and second pattern electrodes 141A and 141B which are arranged one above the other through an insulating layer 13A and connected in parallel, And a pair of lead electrodes 142A, 142B, 143A, 143B drawn from both ends of the second pattern electrodes 141A, 141B to the first external electrodes 16A, 16B, respectively, and one lead electrode 142A, 143A. Are connected to one first external electrode 16A, and the other lead electrodes 142B and 143B are connected to the other first external electrode 16B. The first coil electrode 14 is configured by connecting the upper and lower two layers of the first and second pattern electrodes 141A and 141B in parallel via the first external electrodes 16A and 16B. Resistance is low.

  In the first coil electrode 14, the first pattern electrode 141A is positioned on the inner side (lower side) in the vertical direction, and the second pattern electrode 141B is positioned on the outer side (upper side) in the vertical direction. In the second coil electrode 15, the first pattern electrode 151A is positioned on the inner side (upper side) in the vertical direction, and the second pattern electrode 151B is positioned on the outer side (lower side) in the vertical direction. The line widths of the first pattern electrodes 141A and 151A are smaller than the line widths of the second pattern electrodes 141B and 151B, respectively, and are formed as small areas. By reducing the area of the first pattern electrodes 141A and 151A that face each other of the upper and lower first and second coil electrodes 14 and 15, it is possible to reduce the common mode impedance and the coupling between the coils 14 and 15 without reducing the coupling degree. , And the characteristic impedance of the coil component 10 can be increased. Further, even if the line widths of the first pattern electrodes 141A and 151A are narrow, by increasing the line widths of the second pattern electrodes 141B and 151B, an increase in DC resistance of the first and second coil electrodes 14 and 15 is avoided. can do.

  Next, a parallel connection structure of the first and second pattern electrodes 141A and 141B will be described with reference to FIGS. In FIG. 2A, the first pattern electrode 141A is indicated by a broken line. In FIGS. 2B and 2C, the first pattern electrode 141A having a narrow line width is indicated by a thin line, the second pattern electrode 141B having a large line width is indicated by a thick line, and the direction of current is indicated by an arrow. It is.

  As shown in FIG. 2A and FIG. 3, the first electrode pattern 141A draws a rectangular spiral clockwise starting from one lead electrode 142A and ends at the approximate center of the insulating layer 13B. Since the other lead electrode 142B of the first electrode pattern 141A is located outside the first pattern electrode 141A on the insulating layer 13B, the other lead electrode 142B and the end point of the first pattern electrode 141A are connected to the insulating layer 13B. As shown in FIG. 3, the section where the end point of the first electrode pattern 141A and the other lead electrode 142B cannot be directly connected is divided, as shown in FIG. The lead wire 141B takes over.

  On the other hand, as shown in FIG. 2A and FIG. 3, the second pattern electrode 141B is spirally drawn in the clockwise direction starting from one extraction electrode 143A as in the case of the first pattern electrode 141A. The approximate center is the end point. The end point and the other lead electrode 143B arranged outside the second pattern electrode 141B are connected to each other by the lead wire 144 on the insulating layer 13A. The lead wire 144 replaces the lead wire of the first pattern electrode 141A. Then, the current of the first pattern electrode 141A is temporarily merged with the second pattern electrode 141B through the lead-out wiring 144.

  That is, as shown in FIG. 2B, the end point of the first pattern electrode 141A and the end point of the second pattern electrode 141B (also one end of the lead-out wiring 144) are via holes penetrating the central portion of the insulating layer 13A. The first pattern electrode 141A is electrically connected via the conductor 145A, and the lead wiring 144 of the second pattern electrode 141B is used. Further, the other end of the lead wiring 144 positioned outside the second pattern electrode 141B is connected to the lead electrode 142B of the first pattern electrode 141A via a via-hole conductor (not shown) that similarly penetrates the insulating layer 13A. Electrically connected. As a result, the current of the first pattern electrode 141A merges with the current of the second pattern electrode 141B at one end of the lead wiring 144, and returns to the lead electrodes 142B and 143B at the other end of the lead wiring 144.

  Further, in the second pattern electrode 141B, the portion through which the lead-out wiring 144 passes is divided as shown in FIG. 2A and FIG. 3, so the first pattern electrode 141A takes over this portion. Also in this case, the dividing points of the second pattern electrode 141B facing each other on both sides of the lead-out wiring 144 are the first pattern via via-hole conductors 145B and 145C penetrating the insulating layer 13A as shown in FIG. It is electrically connected to the electrode 141A. The current of the second pattern electrode 141B merges with the current of the first pattern electrode 141A at the via hole conductor 145B, and returns to the second pattern electrode 141B via the via hole conductor 145C.

  Similarly to the first coil electrode 14, the second coil electrode 15 also has first and second pattern electrodes 151 A and 151 B and respective extraction electrodes 152 A, 152 B, 153 A and 153 B. It is configured accordingly. However, the first pattern electrode 151A is located on the upper side as described above, and the second pattern electrode 151B is located on the lower side.

  The conductive material for the first and second coil electrodes 14 and 15 and the via-hole conductor is not particularly limited as long as it is a metal having excellent conductivity. Examples of such a metal include Ag, Pd, Cu, and Al. Can be used.

  Thus, when the coil component 10 is manufactured, for example, an insulating layer is formed using a spin coating method, and a coil electrode is formed on the insulating layer using a sputtering method. When patterning the via hole and the coil electrode layer of the insulating layer, respectively, a photolithography technique and an etching technique are used to form and laminate each layer. For example, an insulating material (for example, polyimide resin) is applied on the magnetic substrate 11 prepared in advance to form the insulating layer 13A, heated and cured (cured), and then cooled. Next, after forming a conductive layer on the insulating layer 13A by sputtering, a photosensitive resist material is applied on the conductive layer, and the resist material layer is exposed and developed through a photomask. Is etched to form the second pattern electrode 151B of the second coil electrode 15, and then the resist is peeled off.

  Subsequently, a photosensitive insulating material (for example, a polyimide resin imparted with photosensitivity) is applied and dried to form an insulating layer 13A. After exposure and development through a photomask, via holes are formed in a predetermined pattern, Heat and cure. Further, after forming a conductive layer by a sputtering method, a photosensitive resist material is applied on the conductive layer, this resist material layer is exposed and developed through a photomask, and then the conductive layer is etched and etched. After forming the first pattern electrode 151A of the two-coil electrode 15, the resist is peeled off. As a result, the first and second pattern electrodes 151A and 151B of the second coil electrode 15 are electrically connected via the via-hole conductor.

  Then, after the insulating layers 13B and 13B between the second coil electrode 15 and the first coil electrode 14 are continuously formed as described above, the first pattern electrode 141A of the first coil electrode 14 is formed on the insulating layer 13B. Then, the second pattern electrode 141B is sequentially formed on the insulating layer 13A, the uppermost insulating layer 13A is formed, and a circuit laminate is formed on the magnetic substrate 11.

  After forming the circuit laminate, the magnetic substrate 12 is heated and pressed to adhere to the upper surface of the circuit laminate via the adhesive layer 18 in an inert gas atmosphere or under vacuum, and the plurality of coil component bodies 10A are collectively bonded. To make. Next, after cutting and dividing into individual coil component bodies 10A by cutting such as dicing, the first external electrodes 16A and 16B and the second external electrodes 17A and 17B are provided to obtain the coil component 10.

  As described above, according to the present embodiment, the pair of upper and lower magnetic substrates 11 and 12, the nonmagnetic layer 13 interposed between these magnetic substrates 11 and 12, and the inside of the nonmagnetic layer 13 And a pair of first and second coil electrodes 14 and 15 that are spaced apart from each other in the vertical direction and are arranged vertically symmetrically to face each other, and the pair of first and second coil electrodes 14 and 15 includes The first and second pattern electrodes 141A and 141B and the first and second pattern electrodes 151A and 151B, which are spaced apart from each other via the insulating layer 13A and have two layers, and a pair The first and second coil electrodes 14 and 15 are arranged on the innermost sides in the vertical direction, and the line widths of the first pattern electrodes 141A and 151A facing each other are the lines of the other second pattern electrodes 141B and 151B, respectively. For smaller, it can be downsized and low profile, wide range of acquisition impedance, high degree of coupling between the coils, the direct current resistance is low and can be set high characteristic impedance.

  Next, a case where the characteristic impedance is set low based on the embodiment shown in FIG. 4 will be described. In the following, the same or corresponding parts as those in the above embodiment are denoted by the same reference numerals, and the features of this embodiment will be mainly described. The other parts of the coil parts of this embodiment are the same as those in the above embodiments. It is configured.

  For example, as shown in FIG. 4, the coil component 10 of the present embodiment includes a pair of upper and lower magnetic substrates 11, 12, a nonmagnetic layer 13 interposed between the magnetic substrates 11, 12, A pair of first and second coil electrodes 14 and 15 which are formed in the magnetic layer 13 so as to be spaced apart from each other and are opposed to each other via an insulating layer 13B. , 15 have spiral first pattern electrodes 141A, 151A and second pattern electrodes 141B, 151B that are spaced apart from each other with an insulating layer 13B therebetween.

  The line widths of the first pattern electrodes 141A and 151A facing each other of the first and second coil electrodes 14 and 15 are set wider than the line widths of the second pattern electrodes 141B and 151B, and the first pattern electrodes 141A, The area of 151A is formed larger than the areas of the second pattern electrodes 141B and 151B. Therefore, the capacitance between the first pattern electrodes 151A and 151A can be increased, and the characteristic impedance of the coil component 10 can be set low.

  As described above, when the areas of the first pattern electrodes 141A and 151A are increased, the number of turns of the first pattern electrodes 141A and 151A is reduced due to space restrictions, and there is a possibility that a necessary inductance value cannot be obtained. Therefore, when a necessary inductance value cannot be obtained, the number of turns of the second pattern electrodes 141B and 151B is increased to supplement the shortage of the first pattern electrodes 141A and 151A. When a necessary inductance value is obtained, the first and second pattern electrodes 141A and 141B may be connected in parallel as in the above embodiment. In the present embodiment, as shown in FIG. 4, the first pattern electrodes 141A and 151A and the second pattern electrodes 141B and 151B are connected in series, and the number of turns of the second pattern electrodes 141B and 151B is set to the first pattern electrodes 141A and 151A. The required inductance value is obtained by increasing the number of turns.

  The series connection structure of the first pattern electrode 141A and the second pattern electrode 141B of the first coil electrode 14 will be described. As shown in FIG. 4, the lead electrode 142A that is the starting point (outer end) of the first pattern electrode 141A is magnetic. It is located on one side of the body substrates 11 and 12, and its end point (inner end) is located inside the first pattern electrode 141A. The start point (inner end) of the second pattern electrode 141B is located immediately above the inner end of the first pattern electrode 141A, and the lead electrode 143B as the end point (outer end) is one side surface of the magnetic substrates 11 and 12. Located on the side facing the. The first and second pattern electrodes 141A and 141B are connected to each other at their inner ends via via-hole conductors 145. The second coil electrode 15 is also connected in series according to the first coil electrode 14. In FIG. 4, reference numeral 155 denotes a via-hole conductor that connects the first pattern electrode 151A and the second pattern electrode 151B of the second coil electrode 15.

  As described above, according to this embodiment, the line widths of the first pattern electrodes 141A and 151A of the first and second coil electrodes 14 and 15 facing each other are set to the line widths of the second pattern electrodes 141B and 151B. Since the area is increased by increasing the area, the capacitance between the first and second coil electrodes 14 and 15 is increased, and the characteristic impedance can be set low. In addition, even if the area of the first pattern electrodes 141A and 151A is increased and the number of turns is reduced, the number of turns of the second pattern electrodes 141B and 151B connected in series to the pattern electrodes 141A and 151A is increased. A necessary impedance value can be secured. In the present embodiment, it is possible to achieve the same effects as the above embodiment except that the characteristic impedance can be lowered.

  In each of the above embodiments, the case where the first and second coil electrodes 14 and 15 have the two-layer pattern electrodes of the first pattern electrodes 141A and 151A and the second pattern electrodes 141B and 151B has been described. There may be three or more pattern electrodes. In the above embodiment, the first pattern electrode 141A of the first coil electrode 14 is the lower layer and the second pattern electrode 141B is the upper layer. However, the first pattern electrode 141A is the upper layer and the second pattern electrode 141B is the lower layer. There may be. In this case, the second pattern electrode 141B of the first coil electrode 14 and the first pattern electrode 151A of the second coil electrode 15 face each other. In short, among the multiple layers of pattern electrodes of the first and second coil electrodes, the areas of the pattern electrodes of the first and second coil electrodes facing each other directly differ from the areas of the other pattern electrodes. I just need it.

  INDUSTRIAL APPLICABILITY The present invention can be widely used for coil parts that can be suitably used as a common mode choke coil for high-speed operation transmission lines of digital equipment such as personal computers.

Claims (4)

  A pair of upper and lower magnetic substrates, a nonmagnetic layer interposed between the magnetic substrates, and a pair of first magnetic layers formed in the nonmagnetic layer so as to be spaced apart from each other in the vertical direction and disposed opposite to each other. 1 and a second coil electrode, wherein the first and second coil electrodes each have at least two layers of spiral first and second pattern electrodes spaced apart from each other, The first pattern electrodes of the first and second coil electrodes are arranged on the innermost side in the vertical direction and face each other, and the areas of the first pattern electrodes are arranged on the outer sides of the second pattern electrodes. Coil parts characterized by being larger or smaller than.   2. The coil component according to claim 1, wherein each of the first and second coil electrodes has a two-layer spiral pattern electrode.   The coil component according to claim 1 or 2, wherein a line width of the first pattern electrode is different from a line width of the second pattern electrode.   4. The coil component according to claim 1, wherein the number of turns of the coil of the first pattern electrode is different from the number of turns of the coil of the second pattern electrode. 5.

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