Laminated coil component

Abstract

The invention relates to a laminated coil component. The laminated coil component includes an element body, a coil disposed in the element body, and an external electrode exposed on the element body. The external electrode is electrically connected to the coil. The element body includes a stress relaxation layer between the coil and the external electrode.

Description

Technical Field

[0001] The present disclosure relates to a laminated coil component. Background Art

[0002] There is known a laminated coil component including a body, a coil disposed in the body, and external electrodes electrically connected to the coil and exposed on the body (for example, Japanese Patent Application Laid-Open No. 2011-009391). The surface of the external electrode forms a mounting surface and faces an electronic device on which the laminated coil component is mounted. Summary of the Invention

[0003] An object of one aspect of the present disclosure is to provide a laminated coil component that alleviates stress acting on the mounting surface.

[0004] The laminated coil component according to one aspect of the present disclosure includes a body, a coil disposed in the body, and external electrodes exposed on the body. The external electrodes are electrically connected to the coil. The body includes a stress alleviation layer located between the coil and the external electrodes.

[0005] The present invention can be more fully understood from the following detailed description and the accompanying drawings, which are given by way of example only and thus should not be considered as limiting the present invention.

[0006] The further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that these detailed descriptions and specific examples, while indicating embodiments of the present invention, are given by way of illustration only, and various changes and modifications within the spirit and scope of the present invention will be apparent to those skilled in the art based on this detailed description. Brief Description of the Drawings

[0007] Figure 1 is a perspective view of a laminated coil component according to a first embodiment.

[0008] Figure 2 is a perspective view of a coil according to a first embodiment.

[0009] Figure 3 is an exploded view showing the structure of a laminated coil component according to a first embodiment.

[0010] Figure 4 is a view showing the structure of a cross-section of a laminated coil component according to a first embodiment.

[0011] Figure 5 is a view showing the structure of a cross-section of a laminated coil component according to a second embodiment.

[0012] Figure 6 is a view showing the structure of a cross-section of a laminated coil component according to a third embodiment.

[0013] Figure 7 This is a diagram showing the cross-sectional structure of the stacked coil component according to the fourth embodiment. Detailed implementation mode

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are assigned to the same elements or elements having the same functions, and repeated descriptions are omitted.

[0015] Refer to Figures 1 to 4 and describe the stacked coil component 1 of the first embodiment. Figure 1 This is a perspective view of the stacked coil component according to the first embodiment. Figure 2 This is a perspective view of the coil according to the first embodiment. Figure 3 This is an exploded view showing the structure of the stacked coil component according to the first embodiment. Figure 4 This is a diagram showing the cross-sectional structure of the stacked coil component according to the first embodiment. As Figure 1 and Figure 2 shown, the stacked coil component 1 includes a body 2, external electrodes 3 and 4, a coil 5, and connection conductors 6 and 7.

[0016] The body 2 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridge lines, and a rectangular parallelepiped shape with rounded corners and ridge lines. The body 2 has a pair of end faces 2a, 2b, a pair of main faces 2c, 2d, and a pair of side faces 2e, 2f as outer surfaces. The end faces 2a, 2b face each other. The main faces 2c, 2d face each other. The side faces 2e, 2f face each other. Hereinafter, the relative direction of the main faces 2c, 2d is set as direction D1, the relative direction of the end faces 2a, 2b is set as direction D2, and the relative direction of the side faces 2e, 2f is set as direction D3. Direction D1, direction D2, and direction D3 are substantially orthogonal to each other.

[0017] The end faces 2a, 2b extend in direction D1 so as to connect the main faces 2c, 2d. The end faces 2a, 2b extend in direction D3 so as to connect the side faces 2e, 2f. The main faces 2c, 2d extend in direction D2 so as to connect the end faces 2a, 2b. The main faces 2c, 2d extend in direction D3 so as to connect the side faces 2e, 2f. The side faces 2e, 2f extend in direction D1 so as to connect the main faces 2c, 2d. The side faces 2e, 2f extend in direction D2 so as to connect the end faces 2a, 2b.

[0018] The main surface 2d is included in the mounting surface, for example, when the stacked coil component 1 is mounted on other electronic devices (not shown), it is the surface facing the other electronic devices. The other electronic devices are, for example, a circuit substrate or a stacked electronic component. The end surfaces 2a, 2b and the side surfaces 2e, 2f are surfaces continuous from the mounting surface. The mounting surface is the main surface 2d.

[0019] The length of the element body 2 in the direction D2 is longer than the length of the element body 2 in the direction D1 and the length of the element body 2 in the direction D3. The length of the element body 2 in the direction D3 is longer than the length of the element body 2 in the direction D1. That is, in the present embodiment, the end surfaces 2a, 2b, the main surfaces 2c, 2d and the side surfaces 2e, 2f are rectangular. The length of the element body 2 in the direction D1 may be equal to the length of the element body 2 in the direction D3, or may be shorter than that length.

[0020] In addition, in the present embodiment, "equal" can be set to be equal not only to the same value, but also to values including a slight difference or manufacturing error within a preset range. For example, if multiple values are within the range of ±20% of the average value of the multiple values, it is stipulated that the multiple values are equal.

[0021] The element body 2 contains a metal component and a resin component. The metal component is, for example, composed of multiple metal particles. In one example, the metal particles are composed of a soft magnetic alloy. The soft magnetic alloy is, for example, an Fe-Si-based alloy. The soft magnetic alloy can be, for example, an Fe-Ni-Si-M-based alloy. "M" includes one or more elements selected from Co, Cr, Mn, P, Ti, Zr, Hf, Nb, Ta, Mo, Mg, Ca, Sr, Ba, Zn, B, Al and rare earth elements. In the element body 2, the metal particles are bonded to each other. The bonding of the metal particles to each other is achieved, for example, by the bonding of oxide films formed on the surfaces of the metal particles. The average particle diameter of the metal particles is 0.5 or more and 15 μm or less. In the present embodiment, the average particle diameter of the metal particles is 5 μm. The "average particle diameter" is calculated, for example, from at least one cross-section of the element body 2. In one example, it refers to the particle diameter when the cumulative value in the particle size distribution obtained by image processing of an image of at least one cross-section of the element body 2 is 50%.

[0022] The resin component is, for example, composed of a resin interposed between multiple metal magnetic particles. The resin can penetrate into the voids existing between adjacent multiple metal magnetic particles. In one example, the resin is composed of an insulating resin having electrical insulation properties. The resin can include, for example, silicone resin, phenolic resin, acrylic resin or epoxy resin.

[0023] The external electrodes 3 and 4 are electrically connected to the coil 5. The external electrodes 3 and 4 are exposed on the base body 2. The external electrodes 3 and 4 are exposed in the same direction as the main surface 2d. The external electrodes 3 and 4 are arranged so as to be exposed only in the same direction as the main surface 2d on the surface of the base body 2. The mounting surface of the base body 2 is constituted by the surfaces of the external electrodes 3 and 4 and the main surface 2d. The external electrode 3 and the external electrode 4 are arranged separately in the direction D2. The external electrode 3 is located near the end face 2a of the base body 2. The external electrode 4 is located near the end face 2b of the base body 2. When observed from the direction D1, the external electrodes 3 and 4 are located at positions away from the ridge line between the main surface 2d and the respective end faces 2a, 2b and side faces 2e, 2f. When observed from the direction D1, the external electrodes 3 and 4 are rectangular. The long sides of the external electrodes 3 and 4 are along the direction D3, and the short sides are along the direction D2.

[0024] The external electrodes 3 and 4 contain a conductive material. The conductive material is, for example, Ag or Pd. The external electrodes 3 and 4 are formed as a sintered body of a conductive paste. The conductive paste contains a conductive metal powder and a glass frit. The conductive metal powder is, for example, Ag powder or Pd powder. A plating layer may be formed on the surfaces of the external electrodes 3 and 4. The plating layer is formed, for example, by electroplating. The electroplating is, for example, Ni electroplating or Sn electroplating. The external electrodes 3 and 4 may also protrude from the main surface 2d.

[0025] The coil 5 is constituted by a plurality of coil conductors 51, 52, 53 and a plurality of via conductors 54, 55. The plurality of coil conductors 51, 52, 53 are arranged in sequence along the direction D1. The coil conductor 51 and the coil conductor 52 are electrically connected to each other via the via conductor 54. The coil conductor 52 and the coil conductor 53 are electrically connected to each other via the via conductor 55. The coil conductor 53 is located at the position closest to the main surface 2d and includes the first end of the coil 5 in the direction D1. The coil conductor 51 is arranged at the position closest to the main surface 2c and includes the second end of the coil 5 in the direction D1. Each of the coil conductors 51 to 53 constitutes a part of the spiral track in the coil 5. The coil 5 contains a conductive material. The conductive material is, for example, Ag, Pd, Cu, Al, or Ni. The plurality of coil conductors 51 to 53 may also be plated conductors.

[0026] The connection conductor 6 is arranged inside the base body 2. The connection conductor 6 connects the external electrode 3 and the coil 5. The connection conductor 6 is a via conductor. The connection conductor 6 extends along the direction D1 and is connected to the external electrode 3 and the first end of the coil 5. The connection conductor 7 is arranged inside the base body 2. The connection conductor 7 connects the external electrode 4 and the coil 5. The connection conductor 7 is a via conductor. The connection conductor 7 extends along the direction D1 and is connected to the external electrode 4 and the second end of the coil 5. The connection conductor 6 and the connection conductor 7 are prism-shaped with the direction D1 as the long side direction.

[0027] As Figure 3As shown, the stacked coil component 1 includes layers La, Lb, Lc, Lc, Ld, Le, Le, Lf, Lg, Lh, Lg, Lg, and Lj stacked in sequence. Layer La includes the main surface 2c, and layer Lj includes the main surface 2d. The thicknesses of the respective layers La to Lj are equal. In one example, the thickness of each of the layers La to Lj is 1 μm or more and 500 μm or less. In the stacked coil component 1, the direction of the specified thickness is along the direction D1.

[0028] In the stacked coil component 1, the substrate 2 includes layers 20a, 20b, 20c, 20c, 20d, 20e, 20e, 20f, 20g, 20h, 20g, 20g, and 20j stacked in sequence. Layer 20h is defined as the stress relaxation layer 21. The layers 20a to 20j are integrated to the extent that the boundaries between the layers cannot be distinguished.

[0029] The coil 5 includes coil conductor layers 50a, a plurality of via conductor layers 50d, coil conductor layer 50b, a plurality of via conductor layers 50e, and coil conductor layer 50c stacked in sequence. In the stacked coil component 1, the number of each of the via conductor layers 50d and 50e is "2". The coil conductor layer 50a constitutes the coil conductor 51, the coil conductor layer 50b constitutes the coil conductor 52, and the coil conductor layer 50c constitutes the coil conductor 53. The plurality of via conductor layers 50d constitute the via conductor 54, and the plurality of via conductor layers 50e constitute the via conductor 55. The coil conductor layers 50a to 50c and the via conductor layers 50d and 50e are integrated to the extent that the boundaries between the layers cannot be distinguished.

[0030] The connection conductor 6 includes a plurality of stacked connection conductor layers 60a. In the stacked coil component 1, the number of the plurality of connection conductor layers 60a is "4". The plurality of connection conductor layers 60a are integrated to the extent that the boundaries between the layers cannot be distinguished. The connection conductor 7 includes a plurality of stacked connection conductor layers 70a. In the stacked coil component 1, the number of the plurality of connection conductor layers 70a is "10". The plurality of connection conductor layers 70a are integrated to the extent that the boundaries between the layers cannot be distinguished. The external electrode 3 includes the external electrode layer 30. The external electrode 4 includes the external electrode layer 40.

[0031] Layer La is constituted by layer 20a. Layer 20a includes the main surface 2c.

[0032] Layer Lb is constituted by layer 20b and the coil conductor layer 50a. The coil conductor layer 50a is provided in the defective portion formed in layer 20b.

[0033] Layer Lc is constituted by layer 20c, the via conductor layer 50d, and the connection conductor layer 70a. The via conductor layer 50d and the connection conductor layer 70a are provided in the defective portion formed in layer 20c.

[0034] The layer Ld is composed of a layer 20d, a coil conductor layer 50b, and a connection conductor layer 70a. The coil conductor layer 50b and the connection conductor layer 70a are provided in a defect portion formed in the layer 20d.

[0035] The layer Le is composed of a layer 20e, a via conductor layer 50e, and a connection conductor layer 70a. The via conductor layer 50e and the connection conductor layer 70a are provided in a defect portion formed in the layer 20e.

[0036] The layer Lf is composed of a layer 20f, a coil conductor layer 50c, and a connection conductor layer 70a. The coil conductor layer 50c and the connection conductor layer 70a are provided in a defect portion formed in the layer 20f.

[0037] The layer Lg is composed of a layer 20g, a connection conductor layer 60a, and a connection conductor layer 70a. The connection conductor layer 60a and the connection conductor layer 70a are provided in a defect portion formed in the layer 20g.

[0038] The layer Lh is composed of a layer 20h, a connection conductor layer 60a, and a connection conductor layer 70a. The connection conductor layer 60a and the connection conductor layer 70a are provided in a defect portion formed in the layer 20h.

[0039] The layer Lj is composed of a layer 20j and external electrode layers 30 and 40. The external electrode layers 30 and 40 are provided in a defect portion formed in the layer Lj. The layer 20j includes a main surface 2d.

[0040] As Figure 4 shown, a stress relaxation layer 21 is located between the coil 5 and the external electrodes 3 and 4. In the direction D1, a portion of the body 2 other than the stress relaxation layer 21 is interposed between the stress relaxation layer 21 and the coil 5. In the direction D1, a portion of the body 2 other than the stress relaxation layer 21 is interposed between the stress relaxation layer 21 and the external electrodes 3 and 4. The stress relaxation layer 21 extends along directions D2 and D3 that intersect the direction D1. The end faces of the stress relaxation layer 21 in the direction D2 may also be included in the end faces 2a and 2b. The end faces of the stress relaxation layer 21 in the direction D3 may also be included in the side faces 2e and 2f. In one example, the thickness of the stress relaxation layer 21 is 1 μm or more and 300 μm or less.

[0041] The stress relaxation layer 21 and the portion of the substrate 2 other than the stress relaxation layer 21 respectively contain a metal component and a resin component. The ratio of the resin component to the metal component in the stress relaxation layer 21 is greater than the ratio of the resin component to the metal component in the portion of the substrate 2 other than the stress relaxation layer 21. The volume content rate of the resin component in the stress relaxation layer 21 may also be greater than the volume content rate of the resin component in the portion of the substrate 2 other than the stress relaxation layer 21. The volume content rate of the resin component is calculated, for example, from the cross-sections of the stress relaxation layer 21 and the portion of the substrate 2 other than the stress relaxation layer 21 respectively. In one example, the volume content rate of the resin component in the stress relaxation layer 21 is at least 1% greater than the volume content rate of the resin component in the portion of the substrate 2 other than the stress relaxation layer 21. The mass content rate of the resin component in the stress relaxation layer 21 may also be greater than the mass content rate of the resin component in the portion of the substrate 2 other than the stress relaxation layer 21. In one example, the mass content rate of the resin component in the stress relaxation layer 21 is at least 1% greater than the mass content rate of the resin component in the portion of the substrate 2 other than the stress relaxation layer 21.

[0042] The ratio of the resin component to the metal component in the stress relaxation layer 21 may also vary according to the position of the stress relaxation layer 21 between the coil 5 and the external electrodes 3 and 4. The position between the coil 5 and the external electrodes 3 and 4 includes the position in the direction D1. For example, the ratio of the resin component to the metal component in the portion of the stress relaxation layer 21 located closer to the external electrodes 3 and 4 may be greater than the ratio of the resin component to the metal component in the portion of the stress relaxation layer 21 located closer to the coil 5.

[0043] The volume content rate of the voids existing between adjacent multiple metal magnetic particles in the stress relaxation layer 21 may also be greater than the volume content rate of the voids existing between adjacent multiple metal magnetic particles in the portion of the substrate 2 other than the stress relaxation layer 21. The voids may also be filled with resin. In one example, the volume content rate of the voids existing between adjacent multiple metal magnetic particles in the stress relaxation layer 21 is at least 1% greater than the volume content rate of the voids existing between adjacent multiple metal magnetic particles in the portion of the substrate 2 other than the stress relaxation layer 21. The density of the stress relaxation layer 21 may also be less than the density of the portion of the substrate 2 other than the stress relaxation layer 21. In one example, the density of the stress relaxation layer 21 is at least 1% less than the density of the portion of the substrate 2 other than the stress relaxation layer 21.

[0044] As described above, the external electrodes 3 and 4 exposed on the substrate 2 are connected to other electronic devices via solder. The external force applied to the mounted multilayer coil component 1 acts as stress on the mounting surface formed by the main surface 2d and the external electrodes 3 and 4. If the stress acting on the mounting surface exceeds the mounting strength, there is a risk that the multilayer coil component 1 will peel off from other electronic devices.

[0045] In the multilayer coil component 1, the base body 2 includes a stress relaxation layer 21 located between the coil 5 and the external electrodes 3 and 4. The external force applied to the multilayer coil component 1 acts on the mounting surface via the stress relaxation layer 21. The stress relaxation layer 21 absorbs the change in stress caused by impact or the like. Therefore, the change in stress generated in the base body 2 hardly acts on the mounting surface. Accordingly, the multilayer coil component 1 relaxes the stress acting on the mounting surface.

[0046] In the base body 2, the stress relaxation layer 21 and the portion other than the stress relaxation layer 21 contain a metal component and a resin component, respectively. The ratio of the resin component to the metal component in the stress relaxation layer 21 is greater than the ratio of the resin component to the metal component in the portion other than the stress relaxation layer 21 of the base body 2.

[0047] The resin component absorbs the change in stress more easily than the metal component. As a result, the multilayer coil component 1 further relaxes the stress acting on the mounting surface.

[0048] The ratio of the resin component to the metal component in the stress relaxation layer 21 may also vary according to the position between the coil 5 and the external electrodes 3 and 4 of the stress relaxation layer 21.

[0049] The vibration applied to the mounted multilayer coil component 1 acts on the base body 2 as stress. The vibration applied to the multilayer coil component 1 acts on the mounting surface via the stress relaxation layer 21. In the structure in which the ratio of the resin component to the metal component in the stress relaxation layer 21 varies according to the position between the coil 5 and the external electrodes 3 and 4 in the stress relaxation layer 21, the vibration frequency absorbed by the stress relaxation layer 21 varies according to the ratio of the resin component to the metal component. As a result, in the structure in which the ratio of the resin component to the metal component in the stress relaxation layer 21 varies according to the position between the coil 5 and the external electrodes 3 and 4 in the stress relaxation layer 21, the range of the vibration frequency absorbed by the stress relaxation layer 21 is wider than that in the structure in which the ratio of the resin component to the metal component in the stress relaxation layer 21 is constant.

[0050] The ratio of the resin component to the metal component in the portion of the stress relaxation layer 21 located closer to the external electrodes 3 and 4 may also be greater than the ratio of the resin component to the metal component in the portion of the stress relaxation layer 21 located closer to the coil 5.

[0051] The portion containing more resin component than the stress relaxation layer 21 is located near the mounting surface. Therefore, the stress acting on the mounting surface can be further relaxed.

[0052] Hereinafter, with reference to Figure 5 , the multilayer coil component 1A according to the second embodiment will be described. Figure 5This is a diagram showing the cross-sectional structure of the stacked coil component according to the second embodiment. Hereinafter, the differences between the stacked coil component 1 according to the first embodiment and the stacked coil component 1A according to the second embodiment will be mainly described.

[0053] In the stacked coil component 1A, the stress relaxation layer 21 overlaps with the external electrodes 3 and 4. In the substrate 2, the stress relaxation layer 21 is located on the external electrodes 3 and 4. In the direction D1, there is no part of the substrate 2 other than the stress relaxation layer 21 between the stress relaxation layer 21 and the external electrodes 3 and 4. In the direction D1, the stress relaxation layer 21 is adjacent to the external electrodes 3 and 4.

[0054] The bending of other electronic devices on which the stacked coil component 1A is mounted acts on the stacked coil component 1A as a bending moment. When a bending moment acts on the stacked coil component 1A, due to the difference between the bending deformation of the substrate 2 and the bending deformation of the external electrodes 3 and 4, there is a risk of cracking between the substrate 2 and the external electrodes 3 and 4.

[0055] In the stacked coil component 1A, since the stress relaxation layer 21 overlaps with the external electrodes 3 and 4, the substrate 2 is more likely to follow the bending deformation of the external electrodes 3 and 4 compared to the structure where a part of the substrate 2 other than the stress relaxation layer 21 overlaps with the external electrodes 3 and 4. Therefore, the stacked coil component 1A has resistance to the bending of other electronic devices on which the stacked coil component 1A is mounted.

[0056] Hereinafter, with reference to Figure 6 , the stacked coil component 1B according to the third embodiment will be described. Figure 6 This is a diagram showing the cross-sectional structure of the stacked coil component according to the third embodiment. Hereinafter, the differences between the stacked coil component 1A according to the second embodiment and the stacked coil component 1B according to the third embodiment will be mainly described.

[0057] In the stacked coil component 1B, the substrate 2 further includes a stress relaxation layer 22 different from the stress relaxation layer 21. The stress relaxation layer 21 is defined as the first stress relaxation layer, and the stress relaxation layer 22 is defined as the second stress relaxation layer. The stress relaxation layer 22 is located between the stress relaxation layer 21 and the coil 5. The stress relaxation layer 22 extends along the direction D2 and the direction D3 that intersect the direction D1. The end face of the stress relaxation layer 22 in the direction D2 may be included in the end faces 2a and 2b. The end face of the stress relaxation layer 22 in the direction D3 may be included in the side faces 2e and 2f.

[0058] The stress relaxation layer 22 is arranged so as to overlap with the coil conductor 53. In the substrate 2, the coil conductor 53 is located on the stress relaxation layer 22. In the direction D1, a part of the substrate 2 other than the stress relaxation layer 21 is interposed between the stress relaxation layer 21 and the stress relaxation layer 22.

[0059] The stress relaxation layer 22 has a ratio of resin component to metal component different from that of the stress relaxation layer 21. The ratio of resin component to metal component in the stress relaxation layer 22 can be smaller than the ratio of resin component to metal component in the stress relaxation layer 21.

[0060] In the stacked coil component 1B, the body 2 includes a stress relaxation layer 21 and a stress relaxation layer 22 located between the stress relaxation layer 21 and the coil 5. The change in stress generated in the body 2 is absorbed by both the stress relaxation layer 21 and the stress relaxation layer 22. Therefore, the stacked coil component 1B further relaxes the stress acting on the mounting surface.

[0061] The stress relaxation layer 22 has a ratio of resin component to metal component different from that of the stress relaxation layer 21. Compared with a structure having the same ratio of resin component to metal component in the stress relaxation layer 21 and the stress relaxation layer 22, in the stacked coil component 1B, the stress relaxation layer 21 and the stress relaxation layer 22 absorb a wider range of vibration frequencies.

[0062] The ratio of resin component to metal component in the stress relaxation layer 21 can be larger than the ratio of resin component to metal component in the stress relaxation layer 22.

[0063] The stress relaxation layer 21 containing more resin component than the stress relaxation layer 22 is located closer to the mounting surface than the stress relaxation layer 22, and thus can further relax the stress acting on the mounting surface. The stress relaxation layer 21 containing more resin component than the stress relaxation layer 22 overlaps with the external electrodes 3 and 4, and therefore, the stacked coil component 1B has resistance to bending of other electronic devices on which the stacked coil component 1B is mounted.

[0064] Hereinafter, with reference to Figure 7 , the stacked coil component 1C according to the fourth embodiment will be described. Figure 7 It is a diagram showing the structure of a cross section of the stacked coil component according to the fourth embodiment. Hereinafter, the differences between the stacked coil component 1A according to the second embodiment and the stacked coil component 1C according to the third embodiment will be mainly described.

[0065] In the multilayer coil component 1C, the body 2 includes a stress relaxation layer 23 instead of the stress relaxation layer 21. The stress relaxation layer 23 has a thickness greater than the thicknesses of the external electrodes 3 and 4. The stress relaxation layer 23 may also have, for example, a thickness more than twice the thicknesses of the external electrodes 3 and 4. The stress relaxation layer 23 is composed of a plurality of layers 20h. In one example, the thickness of the stress relaxation layer 23 is 1 μm or more and 300 μm or less. The stress relaxation layer 23 extends along a direction D2 and a direction D3 that intersect the direction D1. The end faces of the stress relaxation layer 23 in the direction D2 may be included in the end faces 2a and 2b. The end faces of the stress relaxation layer 23 in the direction D3 may be included in the side faces 2e and 2f.

[0066] In the multilayer coil component 1C, the portion of the body 2 closer to one end in the direction D1 than the coil 5 is composed of the stress relaxation layer 23. The stress relaxation layer 23 includes a main face 2d. The thickness of the stress relaxation layer 23 is the distance between the coil 5 and the main face 2d. At least a part of the stress relaxation layer 23 is located in the same layer as the external electrodes 3 and 4. The stress relaxation layer 23 overlaps with the external electrodes 3 and 4. The stress relaxation layer 23 is arranged so as to overlap with the coil conductor 53.

[0067] The stress relaxation layer 23 has a thickness greater than the thicknesses of the external electrodes 3 and 4. The external force applied to the multilayer coil component 1C acts on the mounting surface via the stress relaxation layer 23. Therefore, compared with a structure in which the stress relaxation layer has a thickness smaller than the thicknesses of the external electrodes 3 and 4, in the multilayer coil component 1C, the change in stress generated in the body 2 is less likely to act on the mounting surface.

[0068] As described above, the present disclosure has been described in detail based on its embodiments. However, the present disclosure is not limited to the above embodiments. The present disclosure can be variously modified without departing from its gist. The first embodiment, the second embodiment, the third embodiment, and the fourth embodiment can be appropriately combined.

Claims

1. A stacked coil component, wherein: Comprises: A body; A coil disposed within the body; and External electrodes electrically connected to the coil and exposed on the body, The body includes a stress relaxation layer located between the coil and the external electrodes.

2. The stacked coil component according to claim 1, wherein: The stress relaxation layer and the portion other than the stress relaxation layer in the body respectively contain a metal component and a resin component, The ratio of the resin component to the metal component in the stress relaxation layer is greater than the ratio of the resin component to the metal component in the portion other than the stress relaxation layer of the body.

3. The stacked coil component according to claim 1 or 2, wherein: The stress relaxation layer overlaps with the external electrodes.

4. The stacked coil component according to any one of claims 1 to 3, wherein: The stress relaxation layer includes a first stress relaxation layer, The body further includes a second stress relaxation layer different from the first stress relaxation layer, The second stress relaxation layer is located between the first stress relaxation layer and the coil.

5. The stacked coil component according to claim 4, wherein: The first stress relaxation layer and the second stress relaxation layer respectively contain a metal component and a resin component, The second stress relaxation layer has a ratio of the resin component to the metal component different from that of the first stress relaxation layer.

6. The stacked coil component according to any one of claims 1 to 3, wherein: The stress relaxation layer has a thickness greater than the thickness of the external electrodes.

7. The stacked coil component according to any one of claims 1 to 3, wherein: The stress relaxation layer contains a metal component and a resin component, The ratio of the resin component to the metal component in the stress relaxation layer varies according to the position between the coil and the external electrodes in the stress relaxation layer.

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