Electronic component

Abstract

[Problem] To enhance magnetic characteristics in an electronic component structured so that a coil part is embedded in a magnetic element. [Solution] An electronic component 1 includes a magnetic element M and a coil part 3 embedded in the magnetic element M. Conductor layers C0-C3 included in the coil part 3 have coil patterns 100, 110, 120, 130 overlapping each other when viewed from the Z direction. In the YZ cross section shown in fig. 7, the number of layers of the coil patterns positioned on the side surface 6 side of the magnetic element M is larger than the number of layers of the coil patterns positioned on the side surface 7 side of the magnetic element M. The distance L1 between the coil patterns 100, 110, 120, 130 and the side surface 6 is larger than the distance L2 between the coil patterns 100, 110, 120 and the side surface 7.

Description

Electronic Components

[0001] The present disclosure relates to electronic components.

[0002] Patent Document 1 discloses an electronic component having a structure in which a coil portion, in which a plurality of interlayer insulating films and a plurality of conductor layers are alternately stacked, is embedded in a magnetic base body.

[0003] Japanese Patent Application Laid-Open No. 2017-069523

[0004] In the coil component described in Patent Document 1, the coil portion is located at the center of the magnetic body when viewed in the coil axial direction.

[0005] This disclosure describes a technique for further improving the magnetic properties of an electronic component having a structure in which a coil portion is embedded in a magnetic base body.

[0006] An electronic component according to one aspect of the present disclosure comprises a magnetic base body having first and second side surfaces opposite each other, and a coil portion embedded in the magnetic base body, in which a plurality of interlayer insulating films and a plurality of conductor layers are alternately stacked, and in which the coil axis direction is parallel to the first and second side surfaces, the plurality of conductor layers each have coil patterns that at least partially overlap each other when viewed from the coil axis direction, and are parallel to the coil axis direction, and in a cross section perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface side are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface side are stacked, and the distance between the coil patterns included in the plurality of conductor layers and the first side surface is greater than the distance between the coil patterns included in the plurality of conductor layers and the second side surface.

[0007] An electronic component according to another aspect of the present disclosure includes a magnetic base body having first and second side surfaces opposite each other, and a coil portion embedded in the magnetic base body, the coil portion being formed by alternately stacking a plurality of interlayer insulating films and a plurality of conductor layers, the central axis of which is parallel to the first and second side surfaces, the plurality of conductor layers each having a coil pattern that at least partially overlaps with each other when viewed from the central axis, the plurality of conductor layers being parallel to the central axis, and in a cross section perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface are stacked, the distance from the central axis to the outer peripheral surface of the coil pattern facing the first side surface is equal to or approximately equal to the distance from the central axis to the outer peripheral surface of the coil pattern facing the second side surface, and the central axis is offset toward the second side surface in a direction perpendicular to the first and second side surfaces.

[0008] According to the present disclosure, a technique is provided for further improving the magnetic properties of an electronic component having a structure in which a coil portion is embedded in a magnetic base body.

[0009] FIG. 1 is a schematic perspective view illustrating the appearance of an electronic component 1 according to a first embodiment of the present disclosure. FIG. 2 is a schematic cross-sectional view of the electronic component 1. FIG. 3 is a schematic plan view illustrating the pattern shape of a conductor layer C0. FIG. 4 is a schematic plan view illustrating the pattern shape of a conductor layer C1. FIG. 5 is a schematic plan view illustrating the pattern shape of a conductor layer C2. FIG. 6 is a schematic plan view illustrating the pattern shape of a conductor layer C3. FIG. 7 is a schematic YZ cross-sectional view taken along line A-A shown in FIGS. 3 to 6. FIG. 8 is a schematic plan view illustrating the pattern shape of a conductor layer C0 according to a modified example. FIG. 9 is a schematic plan view illustrating the pattern shape of a conductor layer C1 according to a modified example. FIG. 10 is a schematic plan view illustrating the pattern shape of a conductor layer C2 according to a modified example. FIG. 11 is a schematic plan view illustrating the pattern shape of a conductor layer C3 according to a modified example. FIG. 12 is a schematic YZ cross-sectional view taken along line B-B shown in FIGS. 8 to 11. Fig. 13 is a schematic YZ cross-sectional view taken along line CC shown in Fig. 8 to Fig. 11. Fig. 14 is a schematic cross-sectional view of an electronic component 2 according to a second embodiment of the present disclosure.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0011] FIG. 1 is a schematic perspective view for explaining the appearance of an electronic component 1 according to a first embodiment of the present disclosure.

[0012] As shown in FIG. 1 , the electronic component 1 according to this embodiment is a chip-type coil component having a structure in which a coil portion 3, whose coil axis direction is the Z direction, is embedded in a magnetic body M. When viewed from the Z direction, the magnetic body M is rectangular with its long sides in the X direction and its short sides in the Y direction. The magnetic body M has a mounting surface 4 and a top surface 5 that are orthogonal to the coil axis and form an XY plane, side surfaces 6 and 7 that are parallel to the coil axis and form an XZ plane, and side surfaces 8 and 9 that are parallel to the coil axis and form a YZ plane. The mounting surface 4 and the top surface 5 are located opposite each other. The side surfaces 6 and 7 are located opposite each other. The side surfaces 8 and 9 are located opposite each other. Terminal electrodes E1 and E2 are provided on the mounting surface 4, and during mounting, the terminal electrodes E1 and E2 are soldered to the circuit board so that the mounting surface 4 faces the circuit board. In other words, the up-down orientation of the electronic component 1 shown in FIG. 1 is 180° different from when mounted.

[0013] FIG. 2 is a schematic cross-sectional view of the electronic component 1 according to this embodiment.

[0014] As shown in FIG. 2 , the electronic component 1 according to this embodiment has a coil portion 3 composed of interlayer insulating films 10-14 and conductor layers C0-C3 alternately stacked in the coil axis direction (Z direction). The conductor layers C0-C3 are made of Cu or the like. The magnetic base body M is composed of magnetic resin layers M4 and M10. Of these, the magnetic resin layer M10 includes a magnetic resin layer M1 located in the inner diameter region of the coil portion 3, a magnetic resin layer M2 located in the outer diameter region of the coil portion 3, and a magnetic resin layer M3 located on one side of the coil portion 3 in the coil axis direction (the mounting surface 4 side). The magnetic resin layer M4 is provided on the other side of the coil portion 3 in the coil axis direction (the top surface 5 side). The magnetic resin layers M4 and M10 are composed of a composite magnetic material containing a magnetic filler and a binder resin. The composite magnetic material constituting the magnetic resin layer M4 and the composite magnetic material constituting the magnetic resin layer M10 may be the same material or different materials. The magnetic filler may be a metallic magnetic material such as iron (Fe) or a permalloy material, etc. The binder resin may be an epoxy resin.

[0015] Conductor posts P1 and P2 are embedded in the magnetic resin layer M3. The conductor posts P1 and P2 are made of Cu or the like and are pillar-shaped conductors extending in the Z direction. One end of the conductor post P1, i.e., a bottom surface B, is connected to one end of a coil formed by the conductor layers C0 to C3, and one end of the conductor post P2, i.e., a bottom surface B, is connected to the other end of the coil formed by the conductor layers C0 to C3. Meanwhile, the other ends of the conductor posts P1 and P2, i.e., top surfaces T, are exposed from the mounting surface 4 so as to be flush with the mounting surface 4 and are connected to the terminal electrodes E1 and E2, respectively. The side surfaces S (surfaces along the Z direction) of the conductor posts P1 and P2 are covered with a post protective film 15. Since the post protective film 15 is interposed between the conductor posts P1 and P2 and the magnetic base body M, contact between the conductor posts P1 and P2 and the magnetic base body M is prevented, ensuring insulation between them. Furthermore, when the electronic component 1 of this embodiment having the conductor posts P1, P2 is mounted on a circuit board or the like, the conductor posts P1, P2 relieve stress and reduce damage to the coil portion 3. This also improves the mounting reliability of the electronic component 1.

[0016] The mounting surface 4 and top surface 5 of the magnetic body M are covered with cover insulating films 21 and 22, respectively. The cover insulating film 22 covers almost the entire top surface 5, while the cover insulating film 21 has openings 21a and 21b at positions overlapping with the conductor posts P1 and P2, respectively. This exposes the top surfaces T (XY plane) of the conductor posts P1 and P2 through the openings 21a and 21b of the cover insulating film 21. Terminal electrodes E1 and E2 are provided on the cover insulating film 21. The terminal electrodes E1 and E2 are each formed of a resin electrode 31 containing a metal powder such as Ag and a binder resin, and a Ni film 32 and a Sn film 33 formed on the surface of the resin electrode 31. The terminal electrodes E1 and E2 are connected to the top surfaces T of the conductor posts P1 and P2, respectively, through the openings 21a and 21b of the cover insulating film 21. Although it is not essential to cover the mounting surface 4 and the top surface 5 of the magnetic body M with the cover insulating films 21 and 22, providing the cover insulating film 21 improves reliability by preventing contact between the terminal electrodes E1 and E2 and the magnetic body M. Furthermore, providing the cover insulating film 22 not only improves reliability but also makes it possible to provide a direction mark or the like on the top surface 5.

[0017] 3 to 6 are schematic plan views for explaining the pattern shapes of the conductor layers C0 to C3, respectively.

[0018] As shown in FIG. 3 , a coil pattern 100 is provided on the conductor layer C0. The coil pattern 100 is a pattern that wraps around for approximately one turn, and both ends of the coil pattern 100 are connected to the conductor layer C1 via vias 11a and 11b provided in the interlayer insulating film 11. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 100, and a magnetic resin layer M2 is provided in the outer diameter region of the coil pattern 100. The gap between one end and the other end of the coil pattern 100 is filled with the interlayer insulating film 11. Therefore, the magnetic resin layer M1 and the magnetic resin layer M2 are separated within the plane of the conductor layer C0. The circumferential width of the gap between one end and the other end of the coil pattern 100 is smaller than the pattern width of the coil pattern 100 in the radial direction.

[0019] As shown in FIG. 4 , a coil pattern 110 and a connection pattern 111 are provided on the conductor layer C1. The coil pattern 110 is a pattern that wraps around for approximately one turn, and one end of the coil pattern 110 is connected to the other end of the coil pattern 100 on the conductor layer C0 via a via 11b provided in the interlayer insulating film 11, and the other end is connected to the conductor layer C2 via a via 12b provided in the interlayer insulating film 12. The connection pattern 111 is provided at a position overlapping one end of the coil pattern 100 on the conductor layer C0, and is connected to one end of the coil pattern 100 on the conductor layer C0 via a via 11a provided in the interlayer insulating film 11, and is also connected to the conductor layer C2 via a via 12a provided in the interlayer insulating film 12. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 110, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 110. The gap between one end and the other end of the coil pattern 110 is filled with the interlayer insulating film 12. Therefore, the magnetic resin layer M1 and the magnetic resin layer M2 are separated from each other within the surface of the conductor layer C1. The width of the gap between one end and the other end of the coil pattern 110 in the circumferential direction is smaller than the pattern width of the coil pattern 110 in the radial direction.

[0020] As shown in FIG. 5 , a coil pattern 120 and a connection pattern 121 are provided on the conductor layer C2. The coil pattern 120 is a pattern that wraps around for approximately one turn, and one end of the coil pattern 120 is connected to the other end of the coil pattern 110 on the conductor layer C1 via a via 12b provided in the interlayer insulating film 12, and the other end is connected to the conductor layer C3 via a via 13b provided in the interlayer insulating film 13. The connection pattern 121 is provided at a position overlapping the connection pattern 111 on the conductor layer C1, and is connected to the connection pattern 111 on the conductor layer C1 via a via 12a provided in the interlayer insulating film 12, and is also connected to the conductor layer C3 via a via 13a provided in the interlayer insulating film 13. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 120, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 120. The gap between one end and the other end of the coil pattern 120 is filled with the interlayer insulating film 13. Therefore, the magnetic resin layer M1 and the magnetic resin layer M2 are separated from each other within the surface of the conductor layer C2. The width of the gap between one end and the other end of the coil pattern 120 in the circumferential direction is smaller than the pattern width of the coil pattern 120 in the radial direction.

[0021] As shown in FIG. 6 , a coil pattern 130 and a connection pattern 131 are provided on the conductor layer C3. The coil pattern 130 is a pattern that winds around for approximately 0.5 turns, and one end of the coil pattern 130 is connected to the other end of the coil pattern 120 on the conductor layer C2 via a via 13b provided in the interlayer insulating film 13, and the other end is connected to a conductor post P2 via a via 14b provided in the interlayer insulating film 14. The connection pattern 131 is provided at a position overlapping the connection pattern 121 on the conductor layer C2, and is connected to the connection pattern 121 on the conductor layer C2 via a via 13a provided in the interlayer insulating film 13, and is connected to the conductor post P1 via a via 14a provided in the interlayer insulating film 14. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 130, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 130. A clearance region CL3 where no coil pattern is present is provided between one end and the other end of the coil pattern 130. The clearance region CL3 is a region that divides the coil pattern 130 radially outward from the central axis 40 of the coil portion 3. In the example shown in FIG. 6 , it is provided along the X direction, which is the long side, and the Y direction, which is the short side. The circumferential width of the clearance region CL3 is sufficiently larger than the radial pattern width of the coil pattern 130, for example, approximately 10 times. The clearance region CL3 is not filled with the interlayer insulating film 14, but is filled with a magnetic resin layer M5, which is part of the magnetic resin layer M10. The magnetic resin layer M5 is in contact with the magnetic resin layers M1 and M2. As a result, the magnetic resin layer M1 and the magnetic resin layer M2 are connected via the magnetic resin layer M5 within the plane of the conductor layer C3.

[0022] As a result, coil patterns 100, 110, 120, and 130 are connected in series between terminal electrodes E1 and E2, forming a coil with a total of approximately 3.5 turns. Electronic component 1 according to this embodiment is an embedded-type coil component having a structure in which coil portion 3, formed by alternately stacking interlayer insulating films 10-14 and conductor layers C0-C3, is embedded in magnetic base body M. This structure differs from stacked-type coil components in which magnetic sheets made of ceramic or the like and coil patterns are alternately stacked. For example, in stacked-type coil components, a magnetic sheet is interposed between coil patterns adjacent in the stacking direction, but in electronic component 1 according to this embodiment, adjacent coil patterns in the stacking direction are insulated by an interlayer insulating film, and no magnetic base body M is interposed between them. It also differs in structure from sheet coils in which coil patterns are formed on a printed circuit board.

[0023] FIG. 7 is a schematic YZ cross-sectional view taken along line AA shown in FIGS.

[0024] 7, in the YZ cross section along line A-A, four layers of coil patterns 100, 110, 120, and 130 are located on the side surface 6 (+Y direction side), while three layers of coil patterns 100, 110, and 120 are located on the side surface 7 (-Y direction side). In other words, the number of stacked coil patterns located on the side surface 6 side, i.e., the number of conductor layers C0 to C3 on which coil patterns 100, 110, 120, and 130 are stacked, is one layer more than the number of stacked coil patterns located on the side surface 7 side, i.e., the number of conductor layers C0 to C2 on which coil patterns 100, 110, and 120 are stacked. This is because the coil patterns 100, 110, and 120 located on the conductor layers C0 to C2 all have a pattern of approximately one turn, while the coil pattern 130 located on the conductor layer C3 has a pattern of approximately 0.5 turns.

[0025] In other words, in the conductor layers C0 to C2, coil patterns 100, 110, and 120 appear in two locations each in the YZ cross section along line A-A, whereas in the conductor layer C3, one coil pattern 130 and a clearance area CL3 appear in the YZ cross section along line A-A.

[0026] 3 to 6, in the electronic component 1 according to this embodiment, the distance L1 in the Y direction between the coil patterns 100, 110, 120, and 130 located on the conductor layers C0 to C3 and the side surface 6 of the magnetic body M is greater than the distance L2 in the Y direction between the coil patterns 100, 110, 120 located on the conductor layers C0 to C3 and the side surface 7 of the magnetic body M. As a result, on the side surface 6 side where the number of layers is greater, the volume of the magnetic body M located around the coil patterns 100, 110, 120, and 130 increases, and the inductance of the coil section 3 increases compared to when L1 = L2.

[0027] When the distance L1 varies depending on the position in the X direction, the distance L1 is defined by the shortest distance between the coil pattern and the side surface 6 of the magnetic body M on each of the conductor layers C0 to C3. Similarly, when the distance L2 varies depending on the position in the X direction, the distance L2 is defined by the shortest distance between the coil pattern and the side surface 7 of the magnetic body M on each of the conductor layers C0 to C2. The coil patterns 100, 110, 120, and 130 are arranged so that at least a portion of them overlap each other when viewed from the Z direction, which is the coil axis direction, and when the planar positions of their outer peripheral edges are the same, the distance L1 is the same on each of the conductor layers C0 to C3, and the distance L2 is the same on each of the conductor layers C0 to C2. When there is a difference in the distance L1 between the conductor layers C0 to C3, the distance L1 is defined by the shortest distance between the side surface 6 of the magnetic body M and the coil pattern closest to the side surface 6 of the magnetic body M among the coil patterns 100, 110, 120, and 130. Similarly, if there is a difference in distance L2 between the conductor layers C0 to C2, distance L2 is defined as the shortest distance between the side surface 7 of the magnetic body M and the coil pattern among the coil patterns 100, 110, and 120 that is closest to the side surface 7 of the magnetic body M.

[0028] Note that if the distance in the Y direction from the central axis 40 of the coil unit 3 to the outer peripheral surfaces 100 a, 110 a, and 120 a of the coil patterns 100, 110, and 120 that face the side surface 6 of the magnetic body M is L3, and the distance in the Y direction from the central axis 40 of the coil unit 3 to the outer peripheral surfaces 100 b, 110 b, and 120 b of the coil patterns 100, 110, and 120 that face the side surface 7 of the magnetic body M is L4, the distances L3 and L4 may be equal or approximately equal. That is, L1 > L2 and L3 ≈ L4 may be satisfied. In this case, the central axis 40 of the coil unit 3 is offset toward the side surface 7 in the Y direction. On the other hand, the central axis 40 of the coil unit 3 does not need to be offset in the X direction. That is, the central axis 40 of the coil unit 3 may be located approximately in the center between the side surface 8 and the side surface 9 in the X direction. When there is a difference in the distance L3 between the conductor layers C0 to C2, the distance L3 is defined as the shortest distance.When there is a difference in the distance L4 between the conductor layers C0 to C2, the distance L4 is defined as the shortest distance.

[0029] In this way, in the electronic component 1 according to this embodiment, the coil portion 3 is embedded in the magnetic body M and offset in the -Y direction so as to be away from the side surface 6 of the magnetic body M, and therefore a higher inductance can be obtained compared to when the coil portion 3 is embedded in the center in the Y direction. Moreover, because the side surfaces 6, 7 of the magnetic body M are located on the long side when viewed from the coil axis direction, the inductance-increasing effect achieved by offsetting the coil portion 3 is enhanced compared to when the side surfaces 6, 7 of the magnetic body M are located on the short side.

[0030] The inductance-increasing effect of offsetting the coil portion 3 in the -Y direction becomes more pronounced as the circumferential width of the clearance region CL3 increases. In the example shown in Figure 6, the coil pattern 130 is a pattern with approximately 0.5 turns, so the circumferential width of the clearance region CL3 is also approximately 0.5 turns, and the coil pattern 130 is significantly divided, so the inductance-increasing effect of offsetting the coil portion 3 in the -Y direction becomes more pronounced. In contrast, the circumferential width of the gaps between one end and the other end of the coil patterns 100, 110, and 120 is equal to or less than the radial pattern width of each coil pattern, so offsetting the coil portion 3 in the +X direction where these gaps are located results in almost no change in inductance.

[0031] In this embodiment, the magnetic resin layer M1 located in the inner diameter region of the coil portion 3 and the magnetic resin layer M2 located in the outer diameter region are connected not only via the magnetic resin layers M3 and M4 but also via the magnetic resin layer M5 located in the clearance region CL3 of the conductor layer C3. This increases the volume of the magnetic body M and enables better magnetic properties to be obtained. Furthermore, since the conductor layer C3, in which the clearance region CL3 is formed, is located at one end in the Z direction, the magnetic resin layer M3 and the magnetic resin layer M5 are integrated, thereby enabling further improved magnetic properties. In contrast, the other conductor layers C0 to C2 do not have the clearance region CL3 in which the magnetic resin layer M5 is embedded. Instead, each of the coil patterns 100, 110, and 120 has approximately one turn, ensuring a sufficient number of turns. Note that the coil patterns 100, 110, and 120 provided on the conductor layers C0 to C2 may each have more than one turn.

[0032] 8 to 11 are schematic plan views for explaining the pattern shapes of the conductor layers C0 to C3 according to the respective modifications.

[0033] As shown in Fig. 8, the conductor layer C0 according to the modified example is provided with a coil pattern 100 that winds around for approximately one turn, similar to the conductor layer C0 shown in Fig. 3, and both ends of the coil pattern 100 are connected to the conductor layer C1 via vias 11a and 11b provided in the interlayer insulating film 11. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 100, and a magnetic resin layer M2 is provided in the outer diameter region of the coil pattern 100. The gap between one end and the other end of the coil pattern 100 is filled with the interlayer insulating film 11. Therefore, the magnetic resin layer M1 and the magnetic resin layer M2 are separated within the plane of the conductor layer C0. The circumferential width of the gap between one end and the other end of the coil pattern 100 is smaller than the pattern width of the coil pattern 100 in the radial direction.

[0034] As shown in FIG. 9 , a conductor layer C1 according to the modified example is provided with a coil pattern 110 and a connection pattern 111. The coil pattern 110 is a pattern that winds around approximately 3 / 4 turns, and one end of the coil pattern 110 is connected to the other end of the coil pattern 100 of the conductor layer C0 via a via 11b provided in the interlayer insulating film 11, and the other end is connected to the conductor layer C2 via a via 12b provided in the interlayer insulating film 12. The connection pattern 111 is provided at a position overlapping one end of the coil pattern 100 of the conductor layer C0, and is connected to one end of the coil pattern 100 of the conductor layer C0 via a via 11a provided in the interlayer insulating film 11, and is also connected to the conductor layer C2 via a via 12a provided in the interlayer insulating film 12. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 110, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 110. A clearance region CL1 where no coil pattern is present is provided between one end and the other end of the coil pattern 110. The circumferential width of the clearance region CL1 is sufficiently larger than the radial pattern width of the coil pattern 110, for example, approximately five times larger. The clearance region CL1 is not filled with the interlayer insulating film 12, but is filled with a magnetic resin layer M5, which is part of the magnetic resin layer M10. The magnetic resin layer M5 is in contact with the magnetic resin layers M1 and M2. As a result, the magnetic resin layer M1 and the magnetic resin layer M2 are connected via the magnetic resin layer M5 within the plane of the conductor layer C1.

[0035] As shown in FIG. 10 , the conductor layer C2 according to the modified example is provided with a coil pattern 120 and a connection pattern 121. The coil pattern 120 is a pattern that winds around approximately 3 / 4 turns, and one end of the coil pattern 120 is connected to the other end of the coil pattern 110 of the conductor layer C1 via a via 12b provided in the interlayer insulating film 12, and the other end is connected to the conductor layer C3 via a via 13b provided in the interlayer insulating film 13. The connection pattern 121 is provided at a position overlapping the connection pattern 111 provided in the conductor layer C1, and is connected to the connection pattern 111 of the conductor layer C1 via a via 12a provided in the interlayer insulating film 12, and is also connected to the conductor layer C3 via a via 13a provided in the interlayer insulating film 13. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 120, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 120. A clearance region CL2 where no coil pattern is present is provided between one end and the other end of the coil pattern 120. The circumferential width of the clearance region CL2 is sufficiently larger than the radial pattern width of the coil pattern 120, for example, approximately five times larger. The clearance region CL2 is not filled with the interlayer insulating film 13, but is filled with a magnetic resin layer M5, which is part of the magnetic resin layer M10. The magnetic resin layer M5 is in contact with the magnetic resin layers M1 and M2. As a result, the magnetic resin layer M1 and the magnetic resin layer M2 are connected via the magnetic resin layer M5 within the plane of the conductor layer C2.

[0036] As shown in FIG. 11 , a coil pattern 130 and a connection pattern 131 are provided on the conductor layer C3. The coil pattern 130 is a pattern that wraps around for approximately one turn, and one end of the coil pattern 130 is connected to the other end of the coil pattern 120 on the conductor layer C2 via a via 13b provided in the interlayer insulating film 13, and the other end is connected to a conductor post P2 via a via 14b provided in the interlayer insulating film 14. The connection pattern 131 is provided at a position that overlaps the connection pattern 121 on the conductor layer C2, and is connected to the connection pattern 121 on the conductor layer C2 via a via 13a provided in the interlayer insulating film 13, and is connected to the conductor post P1 via a via 14a provided in the interlayer insulating film 14. A magnetic resin layer M1 is provided in the inner diameter region of the coil pattern 130, and a magnetic resin layer M2 is provided in the outer region of the coil pattern 130. The gap between one end and the other end of the coil pattern 130 is filled with the interlayer insulating film 14. Therefore, the magnetic resin layer M1 and the magnetic resin layer M2 are separated within the surface of the conductor layer C3. The width of the gap between one end and the other end of the coil pattern 130 in the circumferential direction is approximately the same as the pattern width of the coil pattern 130 in the radial direction.

[0037] Fig. 12 is a schematic YZ cross-sectional view taken along line BB shown in Fig. 8 to Fig. 11. Fig. 13 is a schematic YZ cross-sectional view taken along line CC shown in Fig. 8 to Fig. 11.

[0038] 12, in the YZ cross section taken along line B-B, four layers of coil patterns 100, 110, 120, and 130 are located on the side surface 6 side (+Y direction side), while three layers of coil patterns 100, 120, and 130 are located on the side surface 7 side (-Y direction side). Also, as shown in FIG. 13, in the YZ cross section taken along line C-C, four layers of coil patterns 100, 110, 120, and 130 are located on the side surface 6 side (+Y direction side), while three layers of coil patterns 100, 110, and 130 are located on the side surface 7 side (-Y direction side). In other words, in both the YZ cross section taken along line B-B and the YZ cross section taken along line C-C, the number of layers of the coil patterns located on the side surface 6 side is one more than the number of layers of the coil patterns located on the side surface 7 side. This is because the coil patterns 100 and 130 located on the conductor layers C0 and C3 are both patterns that wrap around approximately one turn, while the coil patterns 110 and 120 located on the conductor layers C2 and C3 are both patterns that wrap around approximately 3 / 4 turn.

[0039] That is, in the conductor layers C0, C2, and C3, the coil patterns 100, 120, and 130 appear in two locations each in the YZ cross section taken along line B-B, whereas in the conductor layer C1, the coil pattern 110 appears in one location and a clearance region CL1 in the YZ cross section taken along line B-B. Also, in the conductor layers C0, C1, and C3, the coil patterns 100, 110, and 130 appear in two locations each in the YZ cross section taken along line C-C, whereas in the conductor layer C2, the coil pattern 120 appears in one location and a clearance region CL2 in the YZ cross section taken along line C-C.

[0040] 8 to 11 , even in the coil component according to the modified example, the distance L1 in the Y direction between the coil patterns 100, 110, 120, and 130 located on the conductor layers C0 to C3 and the side surface 6 of the magnetic body M is greater than the distance L2 in the Y direction between the coil patterns 100, 110, 120, and 130 located on the conductor layers C0 to C3 and the side surface 7 of the magnetic body M. As a result, the volume of the magnetic body M located around the coil patterns 100, 110, 120, and 130 increases on the side surface 6 side where the number of layers is greater, and therefore the inductance of the coil portion 3 increases compared to when L1 = L2.

[0041] Furthermore, in the above-described modified example, the magnetic resin layer M1 and the magnetic resin layer M2 are connected via the magnetic resin layer M5 located in the clearance regions CL1 and CL2 of the conductor layers C1 and C2. Here, the conductor layers C1 and C2 having the clearance regions CL1 and CL2 are inner layers that are not located at the ends of the conductor layers C0 to C3 in the axial direction. Therefore, the coil patterns 100 and 130 of the conductor layers C0 and C3 located at the ends in the axial direction can each be approximately one turn, thereby enhancing the overall mechanical strength. Furthermore, the conductor layers C1 and C2 having the clearance regions CL1 and CL2 are adjacent to each other in the axial direction, and the planar positions of these clearance regions CL1 and CL2 are different from each other, making pattern design easy. In this case, the clearance region CL1 of the conductor layer C1 and the clearance region CL2 of the conductor layer C2 do not need to overlap in a planar view in the axial direction.

[0042] FIG. 14 is a schematic cross-sectional view of an electronic component 2 according to the second embodiment of the present disclosure.

[0043] 14 , in the electronic component 2 according to the second embodiment, the terminal electrodes E1, E2 and the cover insulating films 21, 22 are omitted, and the other ends of the conductor posts P1, P2, that is, the top surfaces T, are exposed from the mounting surface 4. The top surfaces T of the conductor posts P1, P2 directly constitute terminal electrodes. Since the other basic configuration is the same as that of the electronic component 1 according to the first embodiment, the same elements are designated by the same reference numerals, and redundant explanations will be omitted.

[0044] As exemplified by the electronic component 2 according to the second embodiment, the upper surfaces T of the conductor posts P1 and P2 may be used as terminal electrodes as they are.

[0045] The above describes embodiments of the technology according to the present disclosure, but the technology according to the present disclosure is not limited to the above embodiments, and various modifications are possible within the scope of the gist of the technology, and it goes without saying that these modifications are also included within the scope of the technology according to the present disclosure.

[0046] For example, in the above embodiment, the coil portion 3 is configured by four conductor layers C0 to C3, but the number of conductor layers included in the coil portion is not particularly limited.

[0047] Furthermore, in the above embodiment, the clearance areas CL1 to CL3 are filled with the magnetic resin layer M5, which is part of the magnetic resin layer M10, but this is not essential to the technology disclosed herein, and the clearance areas CL1 to CL3 may also be filled with an interlayer insulating film.

[0048] The technology according to the present disclosure includes, but is not limited to, the following configuration examples.

[0049] An electronic component according to one aspect of the present disclosure includes a magnetic body having first and second side surfaces opposite to each other, and a coil section embedded in the magnetic body and including a plurality of interlayer insulating films and a plurality of conductor layers alternately stacked, the coil axis direction being parallel to the first and second side surfaces, the plurality of conductor layers each having a coil pattern that at least partially overlaps with each other as viewed from the coil axis direction, the plurality of conductor layers being parallel to the coil axis direction and in a cross section perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface side are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface side are stacked, and the distance between the coil patterns included in the plurality of conductor layers and the first side surface is greater than the distance between the coil patterns included in the plurality of conductor layers and the second side surface, thereby increasing the inductance of the coil section.

[0050] In the electronic component, the plurality of conductor layers may include a first conductor layer having a clearance region in which no coil pattern is present extending radially outward from the central axis of the coil portion, and the coil pattern of the first conductor layer and the clearance region may appear in the cross section. In this way, the volume of the magnetic body located around the coil pattern of the first conductor layer is greater than the volume of the magnetic body located around the clearance region, thereby increasing the inductance of the coil portion.

[0051] In the electronic component, the clearance region may be filled with a magnetic element, which increases the volume of the magnetic element and further increases the inductance of the coil portion.

[0052] In the electronic component, the first conductor layer may be located at one end of the plurality of conductor layers in the coil axis direction, thereby shortening the magnetic path length of the magnetic flux circulating around the coil portion and thereby further improving the magnetic properties.

[0053] The electronic component may further include a terminal electrode covering a mounting surface of the magnetic body perpendicular to the coil axis direction, and a conductor post embedded in the magnetic body, one end connected to one end of the coil pattern located on the first conductor layer, and the other end connected to the terminal electrode, thereby improving the mounting reliability of the electronic component.

[0054] The electronic component may further include a conductor post embedded in the magnetic body, one end connected to one end of the coil pattern located on the first conductor layer, and the other end exposed from the mounting surface of the magnetic body perpendicular to the coil axis direction, which allows the upper surface of the conductor post to be used as a terminal electrode.

[0055] In the electronic component, the magnetic body may have the first and second side faces as long sides when viewed from the coil axis direction. The long sides of the magnetic body have high magnetic flux density, which further improves the magnetic properties.

[0056] According to another aspect of the present disclosure, there is provided an electronic component comprising: a magnetic body having first and second side surfaces opposite to each other; and a coil section embedded in the magnetic body and comprising a plurality of interlayer insulating films and a plurality of conductor layers alternately stacked, the coil section having a central axis parallel to the first and second side surfaces, the plurality of conductor layers each having a coil pattern that at least partially overlaps with each other when viewed from the central axis, the plurality of conductor layers being parallel to the central axis and, in a cross section perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface are stacked, the distance from the central axis to the outer periphery of the coil pattern facing the first side surface is equal to or substantially equal to the distance from the central axis to the outer periphery of the coil pattern facing the second side surface, and the central axis is offset toward the second side surface in a direction perpendicular to the first and second side surfaces, thereby increasing the inductance of the coil section.

[0057] In the electronic component, the magnetic body may further have third and fourth side surfaces located opposite each other, perpendicular to the first and second side surfaces, and parallel to the central axis, and the central axis may be located approximately in the center between the third and fourth side surfaces in the direction perpendicular to the third and fourth side surfaces. This allows the electronic component to be miniaturized.

[0058] This application claims the benefit of Japanese Patent Application No. 2024-032926, filed March 5, 2024, the entire disclosure of which is incorporated herein by reference.

[0059] REFERENCE SIGNS LIST 1, 2 Electronic component 3 Coil portion 4 Mounting surface 5 Upper surface 6 to 9 Side surfaces 10 to 14 Interlayer insulating film 11a, 11b, 12a, 12b, 13a, 13b, 14a, 14b Via 15 Post protective film 21, 22 Cover insulating film 21a, 21b Opening 31 Resin electrode 32 Ni film 33 Sn film 40 Central axis 100, 110, 120, 130 Coil pattern 100a, 100b, 110a, 110b, 120a, 120b Outer circumferential surface 111, 121, 131 Connection pattern B Lower surface of conductor post C0 to C3 Conductor layer CL1 to CL3 Clearance area E1, E2 Terminal electrode M Magnetic base body M1 to M5, M10 Magnetic resin layer P1, P2 Conductor post S Side surface of conductor post T Top surface of conductor post

Claims

1. An electronic component comprising: a magnetic element having first and second side surfaces opposite each other; and a coil portion embedded in the magnetic element, in which a plurality of interlayer insulating films and a plurality of conductor layers are alternately stacked, with the coil axis direction parallel to the first and second side surfaces; wherein the plurality of conductor layers each have coil patterns that at least partially overlap each other when viewed from the coil axis direction, and in a cross section parallel to the coil axis direction and perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface side are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface side are stacked, and the distance between the coil patterns included in the plurality of conductor layers and the first side surface is greater than the distance between the coil patterns included in the plurality of conductor layers and the second side surface.

2. The electronic component according to claim 1, wherein the plurality of conductor layers include a first conductor layer, the first conductor layer having a clearance region in which the coil pattern does not exist extending radially outward from the central axis of the coil portion, and the coil pattern of the first conductor layer and the clearance region appear in the cross section.

3. The electronic component according to claim 2, wherein the clearance area is filled with the magnetic element.

4. The electronic component according to claim 3, wherein the first conductor layer is located at one end of the plurality of conductor layers in the coil axis direction.

5. The electronic component according to claim 4, further comprising: a terminal electrode covering a mounting surface of the magnetic body perpendicular to the coil axis direction; and a conductor post embedded in the magnetic body, one end connected to one end of the coil pattern located on the first conductor layer, and the other end connected to the terminal electrode.

6. The electronic component according to claim 4, further comprising a conductor post embedded in the magnetic body, one end connected to one end of the coil pattern located on the first conductor layer, and the other end exposed from a mounting surface of the magnetic body perpendicular to the coil axis direction.

7. An electronic component according to any one of claims 1 to 6, wherein the magnetic body has long sides, when viewed from the coil axis direction, of which the first and second side surfaces are long sides.

8. An electronic component comprising: a magnetic element having first and second side surfaces opposite to each other; and a coil section embedded in the magnetic element, in which a plurality of interlayer insulating films and a plurality of conductor layers are alternately stacked, the coil section having a central axis parallel to the first and second side surfaces, the plurality of conductor layers each having a coil pattern that at least partially overlaps one another when viewed from the central axis, in a cross section parallel to the central axis and perpendicular to the first and second side surfaces, the number of conductor layers on which the coil patterns located on the first side surface are stacked is greater than the number of conductor layers on which the coil patterns located on the second side surface are stacked, the distance from the central axis to the outer circumferential surface of the coil pattern facing the first side surface is equal to or approximately equal to the distance from the central axis to the outer circumferential surface of the coil pattern facing the second side surface, and the central axis is offset toward the second side surface in a direction perpendicular to the first and second side surfaces.

9. The electronic component according to claim 8, wherein the magnetic body further has third and fourth side surfaces located opposite each other, perpendicular to the first and second side surfaces, and parallel to the central axis, and the central axis is located approximately in the center between the third and fourth side surfaces in the direction perpendicular to the third and fourth side surfaces.

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