Coil component and circuit board including the same

Abstract

To suppress crosstalk in a coil component incorporating a plurality of inductors.SOLUTION: A coil component 1 includes: a magnetic support layer 10; a first coil pattern C1 arranged on a first main surface 11 of the magnetic support layer 10; a second coil pattern C2 arranged on a second main surface 12 of the magnetic support layer 10; a first magnetic resin layer 31 in which the first coil pattern C1 is embedded; and a second magnetic resin layer 32 in which the second coil pattern C2 is embedded. The magnetic support layer 10 has magnetic permeability higher than those of the first and second magnetic resin layers 31 and 32. Thus, since the magnetic permeability of the magnetic support layer 10 is high, magnetic coupling between the first coil pattern C1 and the second coil pattern C2 is suppressed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a coil component and a circuit board including the same, and more particularly to a coil component incorporating a plurality of inductors and a circuit board including the same. [Background technology]

[0002] Patent Document 1 discloses a coil component with multiple inductors built in. By using such a so-called array component, it is possible to reduce the number of components. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-032425 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the coil component described in Patent Document 1 has the problem that the chip size is large because the multiple coils that make up the inductor are simply arranged in one direction, and there is also the problem of crosstalk occurring due to magnetic coupling between adjacent coils.

[0005] Therefore, an object of the present invention is to reduce the chip size of a coil component incorporating multiple inductors and to suppress crosstalk, and to provide a circuit board equipped with such a coil component. [Means for solving the problem]

[0006] The coil component according to the present invention comprises a magnetic support layer having a first main surface and a second main surface located opposite the first main surface, a first coil pattern arranged on the first main surface of the magnetic support layer, a second coil pattern arranged on the second main surface of the magnetic support layer, a first magnetic resin layer provided on the first main surface of the magnetic support layer and embedding the first coil pattern, a second magnetic resin layer provided on the second main surface of the magnetic support layer and embedding the second coil pattern, first and second terminal electrodes exposed from the first magnetic resin layer and connected to one end and the other end of the first coil pattern, respectively, and third and fourth terminal electrodes exposed from the second magnetic resin layer and connected to one end and the other end of the second coil pattern, respectively, wherein the magnetic support layer has a higher magnetic permeability than the first and second magnetic resin layers.

[0007] According to the present invention, the first coil pattern and the second coil pattern are arranged on the front and back of the magnetic support layer, which allows for a reduction in chip size. Furthermore, the high magnetic permeability of the magnetic support layer reduces magnetic coupling between the first coil pattern and the second coil pattern. This allows the first coil pattern and the second coil pattern to function as independent inductors, thereby reducing crosstalk between signals flowing through the first coil pattern and signals flowing through the second coil pattern.

[0008] In the present invention, the magnetic support layer may further have a first side surface orthogonal to the first and second main surfaces and a second side surface opposite the first side surface, wherein the first terminal electrode is exposed from the first side surface of the first magnetic resin layer that is flush with the first side surface of the magnetic support layer, the second terminal electrode is exposed from the second side surface of the first magnetic resin layer that is flush with the second side surface of the magnetic support layer, the third terminal electrode is exposed from the first side surface of the second magnetic resin layer that is flush with the first side surface of the magnetic support layer, and the fourth terminal electrode is exposed from the second side surface of the second magnetic resin layer that is flush with the second side surface of the magnetic support layer. This makes it possible to use the first side surface as an input side and the second side surface as an output side, for example, thereby enabling connections suitable for array products.

[0009] In the present invention, the winding direction of the first coil pattern, which starts from the first terminal electrode and ends at the second terminal electrode, may be opposite to the winding direction of the second coil pattern, which starts from the third terminal electrode and ends at the fourth terminal electrode. This makes it possible to efficiently wind the first and second coil patterns while ensuring a sufficient distance between the first and third terminal electrodes and a sufficient distance between the second and fourth terminal electrodes.

[0010] In the present invention, the conductor width or thickness of the first coil pattern may be different from that of the second coil pattern, thereby reducing the difference in DC resistance caused by the difference in height between the first coil pattern and the second coil pattern.

[0011] The coil component according to the present invention may further include a third coil pattern disposed on the first main surface of the magnetic support layer and embedded in the first magnetic resin layer, a fourth coil pattern disposed on the second main surface of the magnetic support layer and embedded in the second magnetic resin layer, a fifth terminal electrode exposed from the first side surface of the first magnetic resin layer and connected to one end of the third coil pattern, a sixth terminal electrode exposed from the second side surface of the first magnetic resin layer and connected to the other end of the third coil pattern, a seventh terminal electrode exposed from the first side surface of the second magnetic resin layer and connected to one end of the fourth coil pattern, and an eighth terminal electrode exposed from the second side surface of the second magnetic resin layer and connected to the other end of the fourth coil pattern. This makes it possible to provide a coil array having four built-in inductors.

[0012] The coil component according to the present invention may further include a first magnetic cover layer covering the first coil pattern so as to sandwich the first coil pattern between the magnetic support layer and the first magnetic cover layer, and a second magnetic cover layer covering the second coil pattern so as to sandwich the second coil pattern between the magnetic support layer and the first magnetic cover layer. This allows for a higher inductance to be obtained. In this case, the first and second magnetic cover layers may have a higher magnetic permeability than the first and second magnetic resin layers. This allows for an even higher inductance to be obtained. Furthermore, in this case, the first and second magnetic cover layers may be made of the same magnetic material as the magnetic support layer. This allows for a reduction in material costs. Furthermore, the magnetic support layer may be thicker than the first and second magnetic cover layers. This allows for a further reduction in crosstalk.

[0013] A circuit board according to the present invention includes the above-mentioned coil component and a substrate in which the above-mentioned coil component is embedded, the substrate including first to fourth wiring patterns and first to fourth via conductors connecting the first to fourth wiring patterns to the first to fourth terminal electrodes, respectively. This makes it possible to provide a circuit board with a built-in coil array. [Effects of the Invention]

[0014] As described above, the present invention makes it possible to reduce the chip size of a coil component incorporating multiple inductors and suppress crosstalk, and also to provide a circuit board equipped with such a coil component. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1(a) is a schematic perspective view showing the appearance of a coil device 1 according to a first embodiment of the present invention, and FIG. 1(b) is a schematic perspective view of the coil device 1. As shown in FIG. [Figure 2] 2(a) to 2(c) are schematic cross-sectional views taken along lines AA, BB and CC shown in FIG. 1(a), respectively. [Figure 3]3(a) to 3(d) are schematic plan views showing the pattern shapes of the first to fourth conductor patterns L1 to L4, respectively. [Figure 4] FIG. 4 is a schematic cross-sectional view illustrating the structure of a circuit board 100 incorporating the coil component 1. As shown in FIG. [Figure 5] FIG. 5(a) is a schematic perspective view showing the appearance of a coil device 2 according to a second embodiment of the present invention, and FIG. 5(b) is a schematic perspective view of the coil device 2. As shown in FIG. [Figure 6] FIG. 6 is a schematic perspective view of a coil device 3 according to a third embodiment of the present invention. [Figure 7] FIG. 7 is a schematic perspective view of a coil device 4 according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0017] Fig. 1(a) is a schematic perspective view showing the appearance of a coil device 1 according to a first embodiment of the present invention, and Fig. 1(b) is a schematic see-through perspective view of the coil device 1. Also, Figs. 2(a) to 2(c) are schematic cross-sectional views taken along lines AA, BB, and CC, respectively, shown in Fig. 1(a).

[0018] As shown in FIGS. 1 and 2 , the coil component 1 according to the first embodiment includes a magnetic support layer 10, a first magnetic cover layer 21, a second magnetic cover layer 22, a first coil pattern C1 located between the magnetic support layer 10 and the first magnetic cover layer 21, and a second coil pattern C2 located between the magnetic support layer 10 and the second magnetic cover layer 22. The magnetic support layer 10, the first magnetic cover layer 21, and the second magnetic cover layer 22 may be plate-shaped bodies made of a bulk high-permeability material such as ferrite, or may be made of a composite magnetic material in which magnetic particles made of a high-permeability material such as ferrite or permalloy are bound with a resin binder. While the magnetic support layer 10, the first magnetic cover layer 21, and the second magnetic cover layer 22 do not need to be made of the same material, using the same material can reduce material costs. Furthermore, although not particularly limited, the thickness T0 of the magnetic support layer 10 is greater than the thickness T1 of the first magnetic cover layer 21 and the thickness T2 of the second magnetic cover layer 22. It is preferable that the thickness T1 of the first magnetic cover layer 21 and the thickness T2 of the second magnetic cover layer 22 are the same.

[0019] The magnetic support layer 10 has a first main surface 11 and a second main surface 12 located on the opposite side. A first coil pattern C1 is arranged on the first main surface 11, and a second coil pattern C2 is arranged on the second main surface 12. The first coil pattern C1 is embedded in a first magnetic resin layer 31 provided on the first main surface 11 of the magnetic support layer 10. Similarly, the second coil pattern C2 is embedded in a second magnetic resin layer 32 provided on the second main surface 12 of the magnetic support layer 10. An insulating layer 51 is provided between the first coil pattern C1 and the first magnetic resin layer 31 to insulate them from each other. Similarly, an insulating layer 52 is provided between the second coil pattern C2 and the second magnetic resin layer 32 to insulate them from each other. The first and second magnetic resin layers 31 and 32 are made of a composite magnetic material in which magnetic particles made of a high-permeability material such as ferrite or permalloy are bound together with a resin binder.

[0020] The first coil pattern C1 is made up of a first conductor pattern L1 located on the top layer and a second conductor pattern L2 located on the layer below it, while the second coil pattern C2 is made up of a fourth conductor pattern L4 located on the bottom layer and a third conductor pattern L3 located on the layer above it.

[0021] 3(a) to 3(d) are schematic plan views showing the pattern shapes of the first to fourth conductor patterns L1 to L4, respectively.

[0022] As shown in FIG. 3(a), the first conductor pattern L1 has a shape wound clockwise (rightward) by approximately 1 / 2 turn, starting from the first terminal electrode 41 exposed from the first side surface 31S1 of the first magnetic resin layer 31. On the other hand, as shown in FIG. 3(b), the second conductor pattern L2 has a shape wound counterclockwise (leftward) by approximately 1 / 2 turn, starting from the second terminal electrode 42 exposed from the second side surface 31S2 of the first magnetic resin layer 31. An end of the first conductor pattern L1 and an end of the second conductor pattern L2 are connected via a via conductor 61. As a result, the number of turns of the first coil pattern C1 made up of the first and second conductor patterns L1 and L2 is approximately 1 turn, and the winding direction of the first coil pattern C1, starting from the first terminal electrode 41 and ending at the second terminal electrode 42, is clockwise (rightward).

[0023] As shown in FIG. 3(c), the third conductor pattern L3 has a shape wound counterclockwise (left-handed) by approximately 1 / 2 turn, starting from the third terminal electrode 43 exposed from the first side surface 32S1 of the second magnetic resin layer 32. On the other hand, as shown in FIG. 3(d), the fourth conductor pattern L4 has a shape wound clockwise (right-handed) by approximately 1 / 2 turn, starting from the fourth terminal electrode 44 exposed from the second side surface 32S2 of the second magnetic resin layer 32. The end of the third conductor pattern L3 and the end of the fourth conductor pattern L4 are connected via the via conductor 62. As a result, the number of turns of the second coil pattern C2 consisting of the third and fourth conductor patterns L3 and L4 is approximately 1 turn, and the winding direction of the second coil pattern C2, which starts from the third terminal electrode 43 and ends at the fourth terminal electrode 44, is counterclockwise (left-handed).

[0024] Here, the first side surfaces 31S1, 32S1 of the first and second magnetic resin layers 31, 32 are flush with the first side surface 10S1 of the magnetic support layer 10, which is perpendicular to the first and second main surfaces 11, 12. Similarly, the second side surfaces 31S2, 32S2 of the first and second magnetic resin layers 31, 32 are flush with the second side surface 10S2 of the magnetic support layer 10, which is perpendicular to the first and second main surfaces 11, 12. The first side surfaces 10S1, 31S1, 32S1 and the second side surfaces 10S2, 31S2, 32S2 are surfaces located opposite each other.

[0025] The first terminal electrode 41 and the third terminal electrode 43 are provided across the first side surfaces 10S1, 31S1, and 32S1 of the magnetic support layer 10, the first magnetic resin layer 31, and the second magnetic resin layer 32. Similarly, the second terminal electrode 42 and the fourth terminal electrode 44 are provided across the second side surfaces 10S2, 31S2, and 32S2 of the magnetic support layer 10, the first magnetic resin layer 31, and the second magnetic resin layer 32. The cross sections of the first to fourth terminal electrodes 41 to 44 in a planar direction perpendicular to the stacking direction are semicircular. This shape can be obtained by forming through holes by drilling or the like at the boundary between two adjacent coil components 1 when a large number of coil components 1 are obtained using a large-area aggregate substrate, filling the through holes with pillar-shaped conductors, and then dicing the aggregate substrate so that the pillar-shaped conductors are divided into two. In this case, the magnetic support layer 10 itself may be used as the aggregate substrate, or another support may be used as the aggregate substrate, and the first and second coil patterns C1, C2 may be formed on the front and back of the support, respectively, and then the first and second coil patterns C1, C2 may be peeled off from the support and adhered to the magnetic support layer 10.

[0026] In this embodiment, the magnetic material used for the magnetic support layer 10 has a higher magnetic permeability than the magnetic material used for the first and second magnetic cover layers 21, 22. As a result, the magnetic field generated by the current flowing through the first and second coil patterns C1, C2 circulates efficiently via the magnetic support layer 10, and magnetic coupling between them is extremely small. As a result, the first coil pattern C1 and the second coil pattern C2 each function as independent inductors, making it possible to suppress crosstalk between signals flowing through the first coil pattern C1 and signals flowing through the second coil pattern C2.

[0027] This effect becomes more pronounced as the thickness T0 of the magnetic support layer 10 increases. Therefore, in order to more effectively suppress crosstalk while keeping the overall thickness small, it is preferable to make the thickness T0 of the magnetic support layer 10 larger than the thickness T1 of the first magnetic cover layer 21 and the thickness T2 of the second magnetic cover layer 22. As an example, if the thickness T0 of the magnetic support layer 10 is 200 μm, the thicknesses T1 and T2 of the first and second magnetic cover layers 21 and 22 are 70 μm, the magnetic permeability μ′ of the magnetic support layer 10 and the first and second magnetic cover layers 21 and 22 is 40, and the magnetic permeability μ′ of the first and second magnetic resin layers 31 and 32 is 27, the magnetic coupling between the first and second coil patterns C1 and C2 is approximately −0.07. Here, the reason why a material with higher magnetic permeability is used for the magnetic support layer 10 is to increase the inductance of the first and second coil patterns C1, C2 and reduce magnetic coupling therebetween, and the reason why a material with lower magnetic permeability than that of the magnetic support layer 10 is used for the first and second magnetic resin layers 31, 32 is because priority is placed on the embeddability of the first and second coil patterns C1, C2 rather than on magnetic permeability. Also, in order to reduce the difference in inductance between the first coil pattern C1 and the second coil pattern C2, it is preferable that the thickness T1 of the first magnetic cover layer 21 and the thickness T2 of the second magnetic cover layer 22 are the same.

[0028] Furthermore, the magnetic coupling between the first and second coil patterns C1 and C2 is negative because, when the first and third terminal electrodes 41 and 43 are the input side and the second and fourth terminal electrodes 42 and 44 are the output side, the winding directions of the first coil pattern C1 and the second coil pattern C2 are opposite to each other. However, in the present invention, it is not essential that the winding directions of the first coil pattern C1 and the second coil pattern C2 be opposite to each other. However, since the first conductor pattern L1 is connected to the first terminal electrode 41 located on the left side in the plane shown in FIG. 3(a), it can be efficiently wound by winding it clockwise starting from the first terminal electrode 41. On the other hand, since the third conductor pattern L3 is connected to the third terminal electrode 43 located on the right side in the plane shown in FIG. 3(c), it can be efficiently wound by winding it counterclockwise starting from the third terminal electrode 43. Similarly, the second conductor pattern L2 is connected to the second terminal electrode 42 located on the left side in the plane shown in Fig. 3(b), and therefore can be efficiently wound by winding counterclockwise from the second terminal electrode 42 as a starting point, while the fourth conductor pattern L4 is connected to the fourth terminal electrode 44 located on the right side in the plane shown in Fig. 3(d), and therefore can be efficiently wound by winding clockwise from the fourth terminal electrode 44 as a starting point. This makes it possible to efficiently wind the first and second coil patterns C1 and C2 while ensuring a sufficient distance between the first terminal electrode 41 and the third terminal electrode 43, and between the second terminal electrode 42 and the fourth terminal electrode 44, thereby enabling a reduction in chip size.

[0029] In the cross section shown in FIG. 2( a), the first magnetic resin layer 31 is not provided between the second conductor pattern L2 and the first terminal electrode 41, and the space between them is filled with an insulating layer 51. As a result, in this cross section, the first terminal electrode 41 is in contact with the insulating layer 51 without being in contact with the first magnetic resin layer 31, thereby reducing the stray capacitance of the first terminal electrode 41. This increases the self-resonant frequency of the first coil pattern C1. Although not shown, in another cross section, the second magnetic resin layer 32 is not provided between the third conductor pattern L3 and the third terminal electrode 43, and the space between them is filled with an insulating layer 52. As a result, in this cross section, the third terminal electrode 43 is in contact with the insulating layer 52 without being in contact with the second magnetic resin layer 32, thereby reducing the stray capacitance of the third terminal electrode 43. This increases the self-resonant frequency of the second coil pattern C2.

[0030] FIG. 4 is a schematic cross-sectional view illustrating the structure of a circuit board 100 incorporating the coil component 1 according to this embodiment.

[0031] The circuit board 100 shown in FIG. 4 includes a substrate 101 and the above-described coil component 1 embedded therein. The substrate 101 includes a core layer 110 including a core material, resin layers 121-123 that are laminated on the upper surface of the core layer 110 and do not include a core material, and resin layers 124-126 that are laminated on the lower surface of the core layer 110 and do not include a core material. Wiring patterns 130-133 are formed on the upper surface of the core layer 110 and on the surfaces of the resin layers 121-123. Wiring patterns 134-137 are formed on the lower surface of the core layer 110 and on the surfaces of the resin layers 124-126. The wiring patterns 130-133 are connected to each other via a via conductor 141, and the wiring patterns 134-137 are connected to each other via a via conductor 142. The wiring pattern 130 formed on the upper surface of the core layer 110 and the wiring pattern 134 formed on the lower surface of the core layer 110 are connected to each other via a via conductor 140 that penetrates the core layer 110. Terminal electrodes 151 are provided on wiring pattern 133 located in the outermost layer on the upper surface side, and the surface on which terminal electrodes 151 are not provided is covered with solder resist 161. Similarly, terminal electrodes 152 are provided on wiring pattern 137 located in the outermost layer on the lower surface side, and the surface on which terminal electrodes 152 are not provided is covered with solder resist 162.

[0032] An opening 111 is provided in the core layer 110, and the coil component 1 is embedded in this opening 111. In the cross section shown in Fig. 4, the first and second terminal electrodes 41, 42 of the coil component 1 are visible, and a predetermined wiring pattern 131 and the first and second terminal electrodes 41, 42 are connected by via conductors 141, respectively, and a predetermined wiring pattern 135 and the first and second terminal electrodes 41, 42 are connected by via conductors 142, respectively. Although not shown, in another cross section, the predetermined wiring pattern 131 and the third and fourth terminal electrodes 43, 44 are connected by via conductors 141, respectively, and the predetermined wiring pattern 135 and the third and fourth terminal electrodes 43, 44 are connected by via conductors 142, respectively.

[0033] In this way, by embedding the coil component 1 according to this embodiment in the opening 111 provided in the core layer 110, it is possible to provide a circuit board 100 incorporating two independent inductors without increasing the thickness of the substrate 101.

[0034] FIG. 5(a) is a schematic perspective view showing the appearance of a coil device 2 according to a second embodiment of the present invention, and FIG. 5(b) is a schematic perspective view of the coil device 2. As shown in FIG.

[0035] 5, the coil component 2 according to the second embodiment is an array product in which three unit coil portions 1A, 1B, and 1C are arranged in one direction. Each of the unit coil portions 1A, 1B, and 1C has the same structure as the coil component 1 according to the first embodiment. The unit coil portion 1A includes coil patterns C1A and C2A, terminal electrodes 41A and 42A connected to one end and the other end of the coil pattern C1A, respectively, and terminal electrodes 43A and 44A connected to one end and the other end of the coil pattern C2A, respectively. Similarly, the unit coil portion 1B includes coil patterns C1B and C2B, terminal electrodes 41B and 42B connected to one end and the other end of the coil pattern C1B, respectively, and terminal electrodes 43B and 44B connected to one end and the other end of the coil pattern C2B, respectively. The unit coil portion 1C includes coil patterns C1C and C2C, terminal electrodes 41C and 42C connected to one end and the other end of the coil pattern C1C, respectively, and terminal electrodes 43C and 44C connected to one end and the other end of the coil pattern C2C, respectively.

[0036] As a result, the coil component 2 according to this embodiment includes six independent inductors. The coil patterns constituting these six inductors are not simply arranged in one direction, but have a structure in which unit coil portions 1A to 1C, each including two coil patterns located on the front and back of the magnetic support layer 10, are arranged in one direction, making it possible to reduce the planar size compared to when six coil patterns are simply arranged in one direction.

[0037] FIG. 6 is a schematic perspective view of a coil device 3 according to a third embodiment of the present invention.

[0038] As shown in FIG. 6 , the coil component 3 according to the third embodiment differs from the coil component 2 according to the second embodiment in that the terminal electrodes 41A-44A, 41B-44B, and 41C-44C are not pillar-shaped but are formed of conductive films formed on the surface of the element body. Furthermore, in the coil component 3 according to this embodiment, portions of the terminal electrodes 41A-44A, 41B-44B, and 41C-44C are formed around the main surface of the second magnetic cover layer 22. On the other hand, the terminal electrodes 41A-44A, 41B-44B, and 41C-44C are not formed on the main surface of the first magnetic cover layer 21. Therefore, in the coil component 3 according to this embodiment, the second magnetic cover layer 22 side is used as a connection surface. For example, when the coil component 3 according to this embodiment is embedded in a substrate, the coil component 3 is turned upside down from the orientation shown in FIG. 6 , embedded in the substrate with the second magnetic cover layer 22 side facing up, and via conductors are connected to the terminal electrodes formed around the main surface of the second magnetic cover layer 22. Alternatively, when the coil component 3 according to this embodiment is mounted on the surface of a substrate, it may be mounted on the substrate with the second magnetic cover layer 22 facing downward.

[0039] As described above, in the coil component 3 according to this embodiment, the second magnetic cover layer 22 side is used as the connection surface, and therefore, a difference in line length occurs between the upper coil patterns C1A, C1B, and C1C and the lower coil patterns C2A, C2B, and C2C depending on their vertical positions. That is, the lower coil patterns C2A, C2B, and C2C are closer to the main surface of the second magnetic cover layer 22, which is the connection surface, and therefore the route distance of the terminal electrodes is shorter. On the other hand, the upper coil patterns C1A, C1B, and C1C are farther from the main surface of the second magnetic cover layer 22, which is the connection surface, and therefore the route distance of the terminal electrodes is longer. As a result, the upper coil patterns C1A, C1B, and C1C have slightly higher DC resistance than the lower coil patterns C2A, C2B, and C2C. In order to reduce such slight differences in DC resistance, the conductor width or conductor thickness of the coil patterns C1A, C1B, and C1C located on the upper side can be made larger than the conductor width or conductor thickness of the coil patterns C2A, C2B, and C2C located on the lower side.

[0040] Furthermore, since the inductance of the upper coil patterns C1A, C1B, and C1C is slightly greater than that of the lower coil patterns C2A, C2B, and C2C, the difference in inductance may be reduced by slightly differentiating the pattern shapes of the upper coil patterns C1A, C1B, and C1C from those of the lower coil patterns C2A, C2B, and C2C. Alternatively, the difference in inductance may be reduced by differentiating the thicknesses of the first magnetic cover layer 21 and the second magnetic cover layer 22.

[0041] FIG. 7 is a schematic perspective view of a coil device 4 according to a fourth embodiment of the present invention.

[0042] As shown in Fig. 7, the coil component 4 according to the fourth embodiment differs from the coil component 3 according to the third embodiment in that some of the terminal electrodes 41A to 44A, 41B to 44B, and 41C to 44C are formed so as to wrap around to the main surface of the first magnetic cover layer 21. Since the other basic configurations are the same as those of the coil component 3 according to the third embodiment, the same elements are given the same reference numerals and redundant explanations will be omitted. By using the coil component 4 according to the fourth embodiment, it is possible to eliminate the need for a vertical orientation when the coil component 4 is embedded in a substrate 101 as shown in Fig. 4.

[0043] The above describes a preferred embodiment of the present invention, but the present invention is not limited to the above embodiment, and various modifications are possible within the scope of the present invention, and it goes without saying that these modifications are also included within the scope of the present invention. [Explanation of symbols]

[0044] 1~4 Coil parts 1A~1C Unit coil section 10 Magnetic support layer 10S1,31S1,32S1 1st side 10S2,31S2,32S2 2nd side 11 First main surface of magnetic support layer 12 Second main surface of magnetic support layer 21 First magnetic cover layer 22 Second magnetic cover layer 31 First magnetic resin layer 32 Second magnetic resin layer 41 1st terminal electrode 42 2nd terminal electrode 43 3rd terminal electrode 44 4th terminal electrode 41A~44A, 41B~44B, 41C~44C terminal electrode 51,52 Insulating layer 61,62 Via conductor 100 Circuit Boards 101 Substrate 110 Core Layer 111 Opening 121~126 Resin layer 130~137 Wiring pattern 140~142 Via conductor 151,152 terminal electrode 161,162 Solder resist C1 First coil pattern C2 Second coil pattern C1A, C1B, C1C, C2A, C2B, C2C coil pattern L1 First conductor pattern L2 Second conductor pattern L3 Third conductor pattern L4 Fourth conductor pattern

Claims

1. a magnetic support layer having a first major surface and a second major surface opposite the first major surface; a first coil pattern disposed on the first main surface of the magnetic support layer; a second coil pattern disposed on the second main surface of the magnetic support layer; a first magnetic resin layer provided on the first main surface of the magnetic support layer and embedding the first coil pattern; a second magnetic resin layer provided on the second main surface of the magnetic support layer and embedding the second coil pattern; first and second terminal electrodes exposed from the first magnetic resin layer and connected to one end and the other end of the first coil pattern, respectively; third and fourth terminal electrodes exposed from the second magnetic resin layer and connected to one end and the other end of the second coil pattern, respectively; a first magnetic cover layer that covers the first coil pattern so as to sandwich the first coil pattern between the first magnetic cover layer and the magnetic support layer; a second magnetic cover layer that covers the second coil pattern so as to sandwich the second coil pattern between the second magnetic cover layer and the magnetic support layer, the magnetic support layer has a higher magnetic permeability than the first and second magnetic resin layers, The coil component is characterized in that the first and second magnetic cover layers have higher magnetic permeability than the first and second magnetic resin layers.

2. the magnetic support layer further has a first side surface perpendicular to the first and second main surfaces and a second side surface opposite to the first side surface, the first terminal electrode is exposed from a first side surface of the first magnetic resin layer that is flush with the first side surface of the magnetic support layer, the second terminal electrode is exposed from a second side surface of the first magnetic resin layer that is flush with the second side surface of the magnetic support layer, the third terminal electrode is exposed from a first side surface of the second magnetic resin layer that is flush with the first side surface of the magnetic support layer, 2. The coil component according to claim 1, wherein the fourth terminal electrode is exposed from a second side surface of the second magnetic resin layer that is flush with the second side surface of the magnetic support layer.

3. 3. The coil component according to claim 2, wherein a winding direction of the first coil pattern, which starts from the first terminal electrode and ends at the second terminal electrode, is opposite to a winding direction of the second coil pattern, which starts from the third terminal electrode and ends at the fourth terminal electrode.

4. 4. The coil component according to claim 2, wherein a conductor width or a conductor thickness of the first coil pattern is different from a conductor width or a conductor thickness of the second coil pattern.

5. a third coil pattern disposed on the first main surface of the magnetic support layer and embedded in the first magnetic resin layer; a fourth coil pattern disposed on the second main surface of the magnetic support layer and embedded in the second magnetic resin layer; a fifth terminal electrode exposed from the first side surface of the first magnetic resin layer and connected to one end of the third coil pattern; a sixth terminal electrode exposed from the second side surface of the first magnetic resin layer and connected to the other end of the third coil pattern; a seventh terminal electrode exposed from the first side surface of the second magnetic resin layer and connected to one end of the fourth coil pattern; 5. The coil component according to claim 2, further comprising an eighth terminal electrode exposed from the second side surface of the second magnetic resin layer and connected to the other end of the fourth coil pattern.

6. 6. The coil component according to claim 1, wherein the first and second magnetic cover layers are made of the same magnetic material as the magnetic support layer.

7. 7. The coil component according to claim 1, wherein the magnetic support layer is thicker than the first and second magnetic cover layers.

8. The coil component according to any one of claims 1 to 7; a substrate in which the coil component is embedded, The circuit board is characterized in that the substrate includes first to fourth wiring patterns, and first to fourth via conductors that connect the first to fourth wiring patterns to the first to fourth terminal electrodes, respectively.

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