inductive component

Abstract

Provided is an inductance component capable of improving the connection reliability between a coil and external electrodes. The inductance component includes a main body, a coil, and first and second external electrodes electrically connected to the coil. The coil includes a plurality of coil wirings stacked along an axis and a via wiring extending along the axis and connecting adjacent coil wirings in the axis direction. The plurality of coil wirings are each wound along a plane, connected in series, and configured as a spiral. The plurality of coil wirings include a first coil wiring located at a most one side in a direction parallel to the axis and connected to the first external electrode and a second coil wiring located at a most other side in the direction parallel to the axis and connected to the second external electrode. An area of an end surface of one side of the via wiring is smaller than an area of an end surface of the other side of the via wiring. A thickness of the second coil wiring is greater than a thickness of the first coil wiring.

Description

TECHNICAL FIELD

[0001] The present application relates to an inductance component. BACKGROUND

[0002] In the past, as an inductance component, there has been an inductance component described in Japanese Patent Application Publication No. 2015-015297 (Patent Literature 1). The inductance component has a main body, a coil provided inside the main body and wound in a spiral shape along an axis, and two external electrodes provided to the main body and electrically connected to the coil. The main body has a plurality of insulating layers stacked along the axis. The coil has a plurality of coil wirings stacked along the axis. The plurality of coil wirings are each wound in a plane, connected in series, and constitute a spiral.

[0003] Patent Literature 1: Japanese Patent Application Publication No. 2015-015297

[0004] However, it has been found that the above-described conventional inductance component has the following problems in actual manufacturing. That is, it has been found that, if the plurality of insulating layers are stacked with the plurality of coil wirings, the coil wiring of the lowermost layer is connected to one of the external electrodes, and the coil wiring of the uppermost layer is connected to the other external electrode, the thickness of the coil wiring becomes thinner as it goes upward in the stacking direction. Moreover, it has been found that, because the thickness of the coil wiring of the uppermost layer becomes thin, there is a concern that the connection reliability between the coil wiring of the uppermost layer and the other external electrode is reduced.

[0005] Here, the present inventors have earnestly studied the above-described phenomenon, and as a result, have found the following reasons.

[0006] If the plurality of layers are formed by alternately printing the insulating paste that becomes the insulating layer and the conductor paste that becomes the coil wiring, at the upper surface of a prescribed insulating paste layer, the portion of the insulating paste layer that overlaps the conductor paste of the lower layer is formed in a convex shape due to the thickness of the conductor paste. Therefore, when a mask composed of an emulsion (emulsion agent) applied on the surface of a screen is used, because the emulsion is not hard, if the conductor paste is printed while pressing the mask on the upper surface of the insulating paste layer with a squeegee, the emulsion that is in close contact with the convex portion of the upper surface of the insulating paste layer is flattened and its thickness becomes thin. In this way, if the thickness of the emulsion becomes thin, the amount of the conductor paste filled in the emulsion becomes less, and as a result, the thickness of the conductor paste printed on the upper surface of the insulating paste layer becomes thin.

[0007] Moreover, the more the upper surface of the insulating paste layer goes upward in the stacking direction, the thicker the convex portion of the upper surface of the insulating paste layer becomes, and the thickness of the conductor paste stacked on the convex portion becomes more likely to become thin. In this way, in a build-up method such as a printing and stacking method, as the number of layers to be stacked increases, the thickness of the convex portion on the upper surface of the insulating paste layer gradually accumulates and increases, and therefore the thickness of the conductor paste stacked on the convex portion gradually becomes thin. SUMMARY

[0008] To achieve the above object, the present disclosure provides an inductance component capable of improving connection reliability between a coil and an external electrode.

[0009] To achieve the above object, the present disclosure provides an inductance component capable of improving connection reliability between a coil and an external electrode.

[0010] a main body;

[0011] a coil provided in the main body and wound in a spiral shape along an axis, and

[0012] a first external electrode and a second external electrode provided in the main body and electrically connected to the coil,

[0013] the main body has a plurality of insulating layers stacked along the axis,

[0014] the coil has a plurality of coil wirings stacked along the axis, and a via wiring extending along the axis and connecting the coil wirings adjacent in the axis direction,

[0015] the plurality of coil wirings are each wound in a plane and connected in series to constitute a spiral,

[0016] the plurality of coil wirings have a first coil wiring located at a most one side in a direction parallel to the axis and connected to the first external electrode, and a second coil wiring located at a most other side in the direction parallel to the axis and connected to the second external electrode,

[0017] an area of an end surface of the one side in the direction parallel to the axis in the via wiring is smaller than an area of an end surface of the other side in the direction parallel to the axis in the via wiring,

[0018] a thickness of the second coil wiring in the direction parallel to the axis is greater than a thickness of the first coil wiring in the direction parallel to the axis.

[0019] According to the above technical solution, the area of the end surface of the one side in the direction parallel to the axis in the via wiring is smaller than the area of the end surface of the other side in the direction parallel to the axis in the via wiring, and therefore, in terms of construction method, the one side in the direction parallel to the axis corresponds to a lower side in the stacking direction, and the other side in the direction parallel to the axis corresponds to an upper side in the stacking direction. Therefore, the second coil wiring is located at the upper side in the stacking direction.

[0020] Further, the thickness of the second coil wire in the direction parallel to the axis is greater than the thickness of the first coil wire in the direction parallel to the axis, and thus the thickness of the second coil wire on the upper side in the stacking direction can be increased. Thus, the connection area of the second coil wire connected to the second external electrode on the upper side in the stacking direction can be increased, and thus the connection reliability between the second external electrode and the second coil wire can be improved. Therefore, the connection reliability between the coil and the external electrode can be improved.

[0021] Further, in one technical solution of the inductive component, there are provided:

[0022] a main body;

[0023] a coil disposed in the main body and wound in a spiral shape along an axis; and

[0024] a first external electrode and a second external electrode disposed in the main body and electrically connected to the coil,

[0025] the main body has a plurality of insulating layers stacked along the axis,

[0026] the coil has a plurality of coil wires stacked along the axis,

[0027] the plurality of coil wires are respectively wound in a plane and connected in series to form a spiral,

[0028] the coil wires are composed of one coil conductor layer or a plurality of coil conductor layers stacked along the axis and connected in parallel,

[0029] the plurality of coil wires have a first coil wire located at the most one side in the direction parallel to the axis and connected to the first external electrode, and a second coil wire located at the most other side in the direction parallel to the axis and connected to the second external electrode,

[0030] the number of layers of the coil conductor layers constituting the second coil wire is greater than the number of layers of the coil conductor layers constituting the first coil wire.

[0031] According to the above technical solution, the number of layers of the coil conductor layers constituting the second coil wire is greater than the number of layers of the coil conductor layers constituting the first coil wire, and thus if the second coil wire is disposed on the upper side in the stacking direction, the number of layers of the coil conductor layers of the second coil wire on the upper side can be increased. Thus, the number of connections of the coil conductor layers connected to the second external electrode on the upper side in the stacking direction can be increased, and thus the connection reliability between the second external electrode and the second coil wire can be improved. Therefore, the connection reliability between the coil and the external electrode can be improved.

[0032] Preferably, in one technical solution of the inductive component,

[0033] The coil has a via wiring that extends along the axis and connects the wirings of the coils adjacent in the direction of the axis,

[0034] The area of the end surface of one side in the direction parallel to the axis in the via wiring is smaller than the area of the end surface of the other side in the direction parallel to the axis in the via wiring.

[0035] According to the above technical solution, the area of the end surface of one side in the direction parallel to the axis in the via wiring is smaller than the area of the end surface of the other side in the direction parallel to the axis in the via wiring, and therefore, in terms of the method, the one side in the direction parallel to the axis corresponds to the lower side in the stacking direction, and the other side in the direction parallel to the axis corresponds to the upper side in the stacking direction. Therefore, the second coil wiring is located at the upper side in the stacking direction, so that the number of layers of the coil conductor layer of the second coil wiring on the upper layer side can be increased. Therefore, the connection reliability between the second external electrode and the second coil wiring at the upper side in the stacking direction can be improved.

[0036] Preferably, in one technical solution of the inductive component,

[0037] The main body includes: first and second end surfaces opposite to each other; first and second side surfaces opposite to each other; a bottom surface connected between the first and second end surfaces and between the first and second side surfaces; and a top surface opposite to the bottom surface,

[0038] The first external electrode is formed from the first end surface to the bottom surface,

[0039] The second external electrode is formed from the second end surface to the bottom surface,

[0040] The coil is wound along the axis in a manner that the axis is parallel to the bottom surface and the axis intersects the first and second side surfaces,

[0041] The coil has: a winding portion wound in a spiral shape; a first lead-out portion connected between a first end of the winding portion and the first external electrode; and a second lead-out portion connected between a second end of the winding portion and the second external electrode,

[0042] When viewed from the direction parallel to the axis, at least one of the first and second lead-out portions has: a horizontal line portion extending in a direction parallel to the bottom surface away from the winding portion at the top surface side of the winding portion; and a vertical line portion connected to the horizontal line portion and extending in a direction orthogonal to the bottom surface toward the bottom surface side.

[0043] Here, the winding portion refers to a portion in which the coils are wound in a spiral shape such that the coils overlap each other when viewed from a direction parallel to the axis.

[0044] According to the above-described technical solution, the at least one lead portion has the horizontal line portion and the vertical line portion, and thus the vertical line portion is isolated from the winding portion by means of the horizontal line portion. In this way, the vertical line portion can be isolated from the winding portion when viewed from a direction parallel to the axis, and thus short circuit between the at least one lead portion and the winding portion can be prevented.

[0045] Preferably, in one technical solution of the inductance component, a shortest distance between the vertical line portion and the winding portion when viewed from a direction parallel to the axis is greater than or equal to 1 / 2 of a line width of the coil wiring constituting the winding portion.

[0046] Here, the line width of the coil wiring refers to a width of the coil wiring in a direction orthogonal to an extending direction when viewed from a direction parallel to the axis.

[0047] According to the above-described technical solution, the vertical line portion can be further isolated from the winding portion when viewed from a direction parallel to the axis, and thus short circuit between the at least one lead portion and the winding portion can be further prevented.

[0048] Preferably, in one technical solution of the inductance component, a line width of the second coil wiring is greater than a line width of the first coil wiring.

[0049] According to the above-described technical solution, the connection area of the second coil wiring connected to the second external electrode can be further increased, and thus the connection reliability between the second external electrode and the second coil wiring can be further improved.

[0050] Preferably, in one technical solution of the inductance component,

[0051] the second coil wiring has a first portion connected to the second external electrode and a second portion other than the first portion,

[0052] a line width of the first portion is greater than a line width of the second portion.

[0053] According to the above-described technical solution, the connection area of the second coil wiring connected to the second external electrode can be further increased, and thus the connection reliability between the second external electrode and the second coil wiring can be further improved.

[0054] According to the inductance component of one embodiment of the present disclosure, the connection reliability between the coil and the external electrode can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a perspective view showing a first embodiment of an inductance component.

[0056] Figure 2 is an exploded perspective view of the inductance component.

[0057] Figure 3 is a perspective top view of the inductance component viewed from above.

[0058] Figure 4 is a schematic view showing another shape of the second coil wiring.

[0059] Figure 5 is a perspective top view of the second embodiment of the inductance component viewed from above.

[0060] Figure 6 is a perspective front view of the third embodiment of the inductance component viewed from a first side surface.

[0061] BRIEF DESCRIPTION OF THE DRAWINGS

[0062] 1, 1A, 1B … inductance component; 10 … main body; 11 … insulating layer; 13 … first side surface; 14 … second side surface; 15 … first end surface; 16 … second end surface; 17 … bottom surface; 18 … top surface; 19 … side surface; 20, 20A, 20B … coil; 21 … first lead-out portion; 22 … second lead-out portion; 22a … horizontal line portion; 22b … vertical line portion; 23 … winding portion; 23a … first end; 23b … second end; 24, 24A … coil wiring; 241, 241A … first coil wiring; 242, 242A … second coil wiring; 242a … first portion; 242b … second portion; 25 … coil conductor layer; 26 … via hole wiring; 26a … first end surface; 26b … second end surface; 30 … first external electrode; 40 … second external electrode; t1 … thickness of the first coil wiring; t2 … thickness of the second coil wiring; h … line width of the coil wiring; h1 … line width of the first portion; h2 … line width of the second portion; L1 … shortest distance between the vertical line portion and the winding portion. DETAILED DESCRIPTION

[0063] Hereinafter, an inductance component of one embodiment of the present disclosure will be described in detail with reference to the illustrated embodiments. In addition, the drawings include partial schematic views and sometimes do not reflect actual dimensions, ratios.

[0064] (First Embodiment)

[0065] Figure 1 is a perspective view of the first embodiment of the inductance component. Figure 2 is an exploded perspective view of the inductance component. As Figure 1 and Figure 2As shown, the inductor component 1 has a main body 10, a coil 20 provided in the main body 10 and wound in a spiral shape along an axis, and a first external electrode 30 and a second external electrode 40 provided in the main body 10 and electrically connected to the coil 20. In Figure 1 The main body 10 is depicted as transparent to enable easy understanding of the configuration, but can also be translucent or opaque.

[0066] The inductor component 1 is electrically connected to wiring of a circuit substrate not shown by means of the first external electrode 30 and the second external electrode 40. The inductor component 1 is used, for example, as an impedance matching coil of a high-frequency circuit, for electronic devices such as personal computers, DVD players, digital cameras, TVs, cell phones, car electronics, medical / industrial machines, and the like. The use of the inductor component 1 is not limited to this, and it can also be used, for example, in a tuning circuit, a filter circuit, or a rectification smoothing circuit, and the like.

[0067] The main body 10 is formed in a substantially rectangular parallelepiped shape. The surface of the main body 10 includes a first end surface 15 and a second end surface 16 that oppose each other, a first side surface 13 and a second side surface 14 that oppose each other, a bottom surface 17 that is connected between the first end surface 15 and the second end surface 16 and between the first side surface 13 and the second side surface 14, and a top surface 18 that opposes the bottom surface 17. Further, as shown, the X direction is a direction orthogonal to the first end surface 15 and the second end surface 16, the Y direction is a direction orthogonal to the first side surface 13 and the second side surface 14, the Z direction is a direction orthogonal to the bottom surface 17 and the top surface 18, and is a direction orthogonal to the X direction and the Y direction.

[0068] The main body 10 is configured by laminating a plurality of insulating layers 11. The insulating layers 11 are composed of, for example, a material in which borosilicate glass is a main component, or a material such as ferrite or resin. The laminating direction of the insulating layers 11 is a direction (Y direction) parallel to the first end surface 15, the second end surface 16, and the bottom surface 17 of the main body 10. That is, the insulating layers 11 are layers that extend in the XZ plane. The "parallel" in the present application is not limited to a strict parallel relationship, and also includes a substantially parallel relationship, taking into account a range of deviation in reality. Further, there are cases in which the interface between the plurality of insulating layers 11 of the main body 10 becomes indistinct due to firing or the like.

[0069] The first external electrode 30 and the second external electrode 40 are made of a conductive material such as Ag, Cu, Au, or the like, or an alloy in which these elements are the main components. The first external electrode 30 is in an L shape formed from the first end surface 15 to the bottom surface 17. The first external electrode 30 is buried in the main body 10 and exposed from the first end surface 15 and the bottom surface 17. The second external electrode 40 is in an L shape formed from the second end surface 16 to the bottom surface 17. The second external electrode 40 is buried in the main body 10 and exposed from the second end surface 16 and the bottom surface 17.

[0070] The first external electrode 30 and the second external electrode 40 have a structure in which a plurality of first external electrode conductor layers 33 and second external electrode conductor layers 43 are buried in the main body 10 (insulating layer 11). The external electrode conductor layers 33 extend along the first end surface 15 and the bottom surface 17, and the external electrode conductor layers 43 extend along the second end surface 16 and the bottom surface 17. Thus, the external electrodes 30, 40 can be buried in the main body 10, and thus the inductor component can be made smaller than in a structure in which the external electrodes are externally mounted on the main body 10. In addition, the coil 20 and the external electrodes 30, 40 can be formed by the same process, and thus the positional relationship between the coil 20 and the external electrodes 30, 40 can be made less likely to deviate, and thus the inductor component 1 can be made less likely to deviate in electrical characteristics.

[0071] The coil 20 is made of the same conductive material as the first external electrode 30 and the second external electrode 40, for example. The coil 20 is wound in a spiral shape in the stacking direction of the insulating layer 11. The first end of the coil 20 is connected to the first external electrode 30, and the second end of the coil 20 is connected to the second external electrode 40. In the present embodiment, the coil 20 is formed integrally with the first external electrode 30 and the second external electrode 40, and there is no clear boundary, but the present embodiment is not limited thereto, and a boundary can exist because the coil and the external electrodes are formed by different types of materials or different types of processes.

[0072] The coil 20 is wound along an axis parallel to the bottom surface 17 and intersecting the first side surface 13 and the second side surface 14. The axis of the coil 20 coincides with the stacking direction (Y direction) of the insulating layer 11. The axis of the coil 20 refers to the central axis of the spiral shape of the coil 20.

[0073] The coil 20 has a winding portion 23, a first lead-out portion 21 connected between the first end of the winding portion 23 and the first external electrode 30, and a second lead-out portion 22 connected between the second end of the winding portion 23 and the second external electrode 40. In the present embodiment, the winding portion 23 is formed integrally with the first lead-out portion 21 and the second lead-out portion 22, and there is no clear boundary, but the present embodiment is not limited thereto, and a boundary can exist because the winding portion and the lead-out portions are formed by different types of materials or different types of processes.

[0074] The winding portion 23 is wound in a spiral shape along the axis. That is, the winding portion 23 refers to a portion in which the coils 20 are wound in a spiral shape so as to overlap each other when viewed from a direction parallel to the axis. The first lead-out portion 21 and the second lead-out portion 22 are portions deviating from the overlapping portion. The winding portion 23 is formed in a substantially rectangular shape when viewed from the axis direction, but is not limited to this shape. The shape of the winding portion 23 may, for example, be a circular shape, an elliptical shape, another polygonal shape, or the like.

[0075] The coil 20 has a plurality of coil wirings 24 stacked along the axis, and a via-hole wiring 26 extending along the axis and connecting the coil wirings 24 adjacent in the axis direction. The plurality of coil wirings 24 are each wound along a plane, are electrically connected in series, and constitute a spiral.

[0076] The coil wiring 24 is formed so as to be wound on a main surface (XZ plane) orthogonal to the axis direction of the insulating layer 11. The number of winding turns of the coil wiring 24 is less than one turn, but can be one turn or more. The via-hole wiring 26 penetrates the insulating layer 11 in the thickness direction (Y direction). Moreover, the coil wirings 24 adjacent in the stacking direction are electrically connected in series by the via-hole wiring 26. In this way, the plurality of coil wirings 24 are electrically connected in series with each other and constitute a spiral. The coil wiring 24 is constituted by one coil conductor layer 25.

[0077] Figure 3 is a perspective view as viewed from above the inductance component. In Figure 3 In the drawing, the main body 10 is depicted as transparent so as to enable easy understanding of the configuration, but can be translucent or opaque.

[0078] As shown in Figure 2 and Figure 3 The plurality of coil wirings 24 have a first coil wiring 241 located at the most one side in the direction parallel to the axis and connected to the first external electrode 30, and a second coil wiring 242 located at the most other side in the direction parallel to the axis and connected to the second external electrode 40. The one side in the direction parallel to the axis refers to a direction opposite to the Y direction (second side surface 14 side), and the other side in the direction parallel to the axis refers to a direction along the Y direction (first side surface 13 side).

[0079] The area of a first end surface 26a of the via-hole wiring 26 on the one side in the direction parallel to the axis is smaller than the area of a second end surface 26b of the via-hole wiring 26 on the other side in the direction parallel to the axis. Thereby, in terms of the work method, the one side in the direction parallel to the axis corresponds to the lower side in the stacking direction, and the other side in the direction parallel to the axis corresponds to the upper side in the stacking direction.

[0080] Specifically, in the manufacturing method of the inductance component 1, the first external electrode 30 and the second external electrode 40 are formed by forming the first external electrode 30 and the second external electrode 40 on the first side surface 13 and the second side surface 14 of the main body 10, respectively, and thenFigure 2 The lower side insulating layer 11 shown is made to alternately stack the coil wire 24 and the insulating layer 11 toward the upper side insulating layer 11 to manufacture the inductance member 1. In addition, in the manufacturing method of the via hole wire 26, for example, an opening is provided on the insulating layer 11 by a photolithography process or a laser process, and the via hole wire 26 is provided on the opening of the insulating layer 11 by, for example, screen printing. At this time, in terms of the process, the opening of the insulating layer 11 is formed so that the inner diameter on the lower side in the stacking direction is smaller than the inner diameter on the upper side in the stacking direction. Therefore, the area of the first end surface 26a of the via hole wire 26 on the lower side in the stacking direction is smaller than the area of the second end surface 26b of the via hole wire 26 on the upper side in the stacking direction.

[0081] According to the above shape of the via hole wire 26, the second coil wire 242 is located at the upper side in the stacking direction, and the first coil wire 241 is located at the lower side in the stacking direction. Also, the thickness t2 of the second coil wire 242 in the direction parallel to the axis is greater than the thickness t1 of the first coil wire 241 in the direction parallel to the axis. Here, the thicknesses t1, t2 refer to the average thickness of the coil wire.

[0082] Further, in the measurement of the average thickness of the coil wire, first, along the longest straight line portion in the coil wire to be measured, the central cross section including the direction parallel to the axis (Y direction) of the straight line portion is exposed by polishing or the like. Next, the cross section is photographed by a scanning electron microscope, and the thickness of the straight line portion in the direction parallel to the axis is measured at five positions and averaged, and the average is taken as the average thickness of the coil wire.

[0083] According to the above structure, the thickness t2 of the second coil wire 242 is greater than the thickness t1 of the first coil wire 241, and thus the thickness t2 of the second coil wire 242 on the upper side in the stacking direction can be increased. Thus, the connection area of the second coil wire 242 at the upper side in the stacking direction to the second external electrode 40 can be increased, and thus the connection reliability between the second external electrode 40 and the second coil wire 242 can be improved. Therefore, the connection reliability between the coil 20 and the external electrodes 30, 40 can be improved.

[0084] Specifically, as explained in the "Background Art (Defects of the Prior Art)" above, in a build-up process such as a printing lamination process, the thicker the protrusions of the upper surface of the insulating paste layer (insulating layer) are, the thinner the thickness of the conductor paste (coil wiring) laminated to the protrusions is, the more the upper side of the lamination direction is. For this reason, the thickness of the conductor paste corresponding to the uppermost layer of the second coil wiring 242 is controlled to be greater than the thickness of the conductor paste corresponding to the lowermost layer of the first coil wiring 241, whereby the thickness t2 of the second coil wiring 242 is made greater than the thickness t1 of the first coil wiring 241. Therefore, the connection area of the second coil wiring 242 to the second external electrode 40 can be increased.

[0085] Further, in terms of the process, the design value of the thickness t1 of the first coil wiring 241 can be ensured, and thus the connection reliability between the first external electrode 30 and the first coil wiring 241 can be ensured. In addition, in terms of the process, the thickness of the coil wiring 24 existing between the first coil wiring 241 and the second coil wiring 242 is smaller than the thickness t1 of the first coil wiring 241, but can also be controlled to be greater than the thickness t1 of the first coil wiring 241.

[0086] Preferably, with reference to Figure 2 , the line width of the second coil wiring 242 is greater than the line width of the first coil wiring 241. The line width of the coil wiring 241, 242 refers to the average size of the size in the direction orthogonal to the extending direction of the coil wiring 241, 242 when viewed from the axial direction.

[0087] Further, in the measurement of the line width of the coil wiring, first, the central cross section of the measured coil wiring is exposed from the axial direction by polishing or the like. Next, the cross section is photographed by a scanning electron microscope, and the line width of the coil wiring is measured at 5 positions and averaged, and the average value is taken as the line width of the coil wiring.

[0088] According to the above structure, the connection area of the second coil wiring 242 to the second external electrode 40 can be further increased, and thus the connection reliability between the second external electrode 40 and the second coil wiring 242 can be further improved.

[0089] Preferably, as Figure 4As shown, the second coil wiring 242 has a first portion 242a connected to the second external electrode 40 and a second portion 242b other than the first portion 242a. The line width h1 of the first portion 242a is larger than the line width h2 of the second portion 242b. The line width h1 of the first portion 242a refers to the line width at the contact surface of the first portion 242a in contact with the second external electrode 40. The line width h2 of the second portion 242b refers to the average dimension of the second portion 242b in the entire extension direction. The first portion 242a preferably corresponds to the second lead portion 22.

[0090] According to the above structure, the connection area of the second coil wiring 242 connected to the second external electrode 40 can be further increased, and thus the connection reliability between the second external electrode 40 and the second coil wiring 242 can be further improved.

[0091] (Second Embodiment)

[0092] Figure 5 is a perspective plan view showing the second embodiment of the inductance component viewed from above. The number of layers of the coil conductor layers of the coil wiring of the second embodiment is different from that of the first embodiment. Hereinafter, the different structure will be described. The other structures are the same as those of the first embodiment, the same reference numerals are assigned, and the description thereof will be omitted. Further, in Figure 5 , for convenience of description, the number of layers of the coil wiring 24A is depicted to be less than that of the coil wiring of Figure 3 .

[0093] As shown in Figure 5 , in the coil 20A of the inductance component 1A of the second embodiment, each coil wiring 24A is composed of a plurality of coil conductor layers 25. In each coil wiring 24A, the plurality of coil conductor layers 25 are stacked along the axis and connected in parallel. The plurality of coil conductor layers 25 are connected in parallel by means of the via conductors 27, but the plurality of coil conductor layers 25 can be connected in parallel by being in surface contact with each other.

[0094] The number of layers of the coil conductor layers 25 constituting the second coil wiring 242A connected to the second external electrode 40 is more than the number of layers of the coil conductor layers 25 constituting the first coil wiring 241A connected to the first external electrode 30. Specifically, the number of layers of the coil conductor layers 25 of the second coil wiring 242A is three layers, and the number of layers of the coil conductor layers 25 of the first coil wiring 241A is two layers. Further, the number of layers of the coil conductor layers 25 of the coil wiring 24A other than the first coil wiring 241A and the second coil wiring 242A is two layers.

[0095] The area of the first end surface 26a of the via wiring 26 is smaller than the area of the second end surface 26b of the via wiring 26. Thus, the second coil wiring 242A is positioned at the upper side in the stacking direction, and the first coil wiring 241A is positioned at the lower side in the stacking direction. Also with respect to the lower end surface and the upper end surface of the via conductor 27, the area of the lower end surface is made smaller than the area of the upper end surface. Further, in the via conductor 27, the area of the lower end surface can be the same as the area of the upper end surface, or can be larger than the area of the upper end surface.

[0096] According to the above-described structure, the number of layers of the coil conductor layers 25 constituting the second coil wiring 242A is larger than the number of layers of the coil conductor layers 25 constituting the first coil wiring 241A, and thus the number of layers of the coil conductor layers 25 of the second coil wiring 242A on the upper layer side can be increased. Thus, the number of connections of the coil conductor layers 25 of the second coil wiring 242A to the second external electrode 40 on the upper side in the stacking direction can be increased, and thus the connection reliability between the second external electrode 40 and the second coil wiring 242A can be improved. Therefore, the connection reliability between the coil 20A and the external electrodes 30 and 40 can be improved.

[0097] Specifically, as described above, in a build-up process such as a printing lamination process, the thicker the protrusions of the upper surface of the insulating paste layer (insulating layer) on the upper side in the stacking direction, the more easily the thickness of the conductor paste (coil wiring) laminated to the protrusions becomes thin. For this reason, the number of layers of the conductor paste corresponding to the uppermost layer of the second coil wiring 242A is controlled to be larger than the number of layers of the conductor paste corresponding to the lowermost layer of the first coil wiring 241A, and thus the number of layers of the coil conductor layers 25 of the second coil wiring 242A is made larger than the number of layers of the coil conductor layers 25 of the first coil wiring 241A. Therefore, the number of connections of the second coil wiring 242A to the second external electrode 40 can be increased. Further, in terms of the process, the design value of the thickness of the first coil wiring 241A can be ensured, and thus even if the number of layers of the coil conductor layers 25 of the first coil wiring 241A is reduced, the connection reliability between the first external electrode 30 and the first coil wiring 241A can be ensured.

[0098] On the other hand, in all of the coil wirings, in the case where the number of layers of the coil conductor layers constituting the coil wirings is the same, if the thickness of the coil conductor layers becomes thinner on the upper layer side in the stacking direction, there is a concern that the connection reliability between the external electrode and the coil wiring on the upper layer side decreases.

[0099] Further, in this embodiment, each of the coil wirings 24A is constituted by a plurality of coil conductor layers 25, but at least one of the coil wirings 24A other than the second coil wiring 242A among all of the coil wirings 24A can be constituted by one coil conductor layer 25.

[0100] In addition, in this embodiment, unlike the first embodiment, the thickness and the line width of the second coil wire 242A in the direction parallel to the axis can be the same as or smaller than the thickness and the line width of the first coil wire 241A in the direction parallel to the axis.

[0101] (Third Embodiment)

[0102] Figure 6 is a perspective front view showing the inductance component of the third embodiment as viewed from the first side surface. The structure of the lead-out portion of the coil of the third embodiment is different from that of the first embodiment. Hereinafter, the different structure will be described. The other structures are the same as those of the first embodiment, and the same reference numerals are given to the same components and the description thereof is omitted.

[0103] As shown in Figure 6 In the coil 20B of the inductance component 1B of the third embodiment, the first lead-out portion 21 is connected between the first end 23a of the winding portion 23 and the first external electrode 30, and the second lead-out portion 22 is connected between the second end 23b of the winding portion 23 and the second external electrode 40. The winding portion 23 is a portion that is wound in a spiral shape and coincides when viewed in the direction parallel to the axis, and thus the first end 23a and the second end 23b are end surfaces that are apart from the portion wound in a spiral shape.

[0104] The first lead-out portion 21 extends to be connected to the first external electrode 30 at the shortest distance from the first end 23a. That is, when viewed in the direction parallel to the axis, the first lead-out portion 21 is inclined with respect to the X direction and the Z direction.

[0105] When viewed in the direction parallel to the axis, the second lead-out portion 22 has a horizontal line portion 22a extending in the X direction from the second end 23b, and a vertical line portion 22b extending in the Z direction from the horizontal line portion 22a. Further, between the vertical line portion 22b and the second external electrode 40, the second lead-out portion 22 extends obliquely with respect to the X direction and the Z direction, and is connected to the second external electrode 40 at the shortest distance from the vertical line portion 22b.

[0106] The horizontal line portion 22a extends away from the winding portion 23 in the direction parallel to the bottom surface 17 at the top surface 18 side of the winding portion 23. Here, the parallel to the bottom surface 17 includes not only the complete parallel to the bottom surface 17 but also the substantially parallel to the bottom surface 17 that is slightly curved with respect to the bottom surface 17.

[0107] The longitudinal line portion 22b is connected to the lateral line portion 22a and extends toward the bottom surface 17 side in a direction orthogonal to the bottom surface 17. Here, the orthogonal to the bottom surface 17 includes not only the complete orthogonal to the bottom surface 17 but also the substantially orthogonal to the bottom surface 17 with a slight inclination from the complete orthogonal to the bottom surface 17.

[0108] According to the above structure, the second lead-out portion 22 has the lateral line portion 22a and the longitudinal line portion 22b, and thus the longitudinal line portion 22b is isolated from the winding portion 23 by the lateral line portion 22a. Thus, the longitudinal line portion 22b can be isolated from the winding portion 23 when viewed from the direction parallel to the axis, and thus the short circuit between the second lead-out portion 22 and the winding portion 23 can be prevented.

[0109] Preferably, the shortest distance L1 between the longitudinal line portion 22b and the winding portion 23 when viewed from the direction parallel to the axis is 1 / 2 or more of the line width h of the coil wiring 24 constituting the winding portion 23. The line width h of the coil wiring 24 of the winding portion 23 refers to the dimension in the direction orthogonal to the extending direction of the coil wiring 24 when viewed from the direction parallel to the axis, and specifically, the width of the portion of the winding portion 23 connected to the second lead-out portion 22, i.e., the second end 23b.

[0110] According to the above structure, the longitudinal line portion 22b can be further isolated from the winding portion 23 when viewed from the direction parallel to the axis, and thus the short circuit between the second lead-out portion 22 and the winding portion 23 can be further prevented.

[0111] Further, in this embodiment, the second lead-out portion 22 has the lateral line portion 22a and the longitudinal line portion 22b, but at least one of the first lead-out portion 21 and the second lead-out portion 22 can have the lateral line portion and the longitudinal line portion. In the case where the first lead-out portion 21 has the lateral line portion and the longitudinal line portion, the longitudinal line portion can be isolated from the winding portion 23, and thus the short circuit between the first lead-out portion 21 and the winding portion 23 can be prevented. In addition, in the case where the first lead-out portion 21 has the lateral line portion and the longitudinal line portion, preferably, the shortest distance between the longitudinal line portion and the winding portion 23 is 1 / 2 or more of the line width h of the coil wiring constituting the winding portion 23. At this time, specifically, the line width of the coil wiring of the winding portion 23 is the width of the portion of the winding portion 23 connected to the first lead-out portion 21, i.e., the first end 23a.

[0112] Further, the present disclosure is not limited to the above-described embodiments, and design changes can be made within the scope of the gist of the present disclosure. For example, the characteristic points of each of the first to third embodiments can be variously combined. Specifically, the thickness of the second coil wiring can be greater than the thickness of the first coil wiring, and the number of layers of the coil conductor layer constituting the second coil wiring can be greater than the number of layers of the coil conductor layer constituting the first coil wiring.

[0113] In the above embodiment, the axis of the coil is orthogonal to the side surface of the main body, but can be orthogonal to the end surface of the main body, or can be orthogonal to the bottom surface of the main body.

[0114] In the above embodiment, the first external electrode and the second external electrode are L-shaped, but for example, can be five-surface electrodes. That is, the first external electrode can be provided to a portion of each of the entire surface of the first end surface, the first side surface, the second side surface, the bottom surface, and the top surface, and the second external electrode can be provided to a portion of each of the entire surface of the second end surface, the first side surface, the second side surface, the bottom surface, and the top surface. Alternatively, the first external electrode and the second external electrode can be provided to portions of the bottom surface, respectively.

[0115] (Embodiment)

[0116] Hereinafter, an embodiment of a manufacturing method of the inductance component 1 will be described.

[0117] First, an operation of applying an insulating paste mainly containing borosilicate glass to a substrate such as a support film by screen printing is repeatedly performed, thereby forming an insulating layer. The insulating layer becomes an insulating layer for an outer layer located outward of the coil conductor layer. In addition, the substrate is peeled from the insulating layer in an arbitrary process and is not left as the inductance component.

[0118] Subsequently, a photosensitive conductive paste layer is formed on the insulating layer, and the coil conductor layer and the external electrode conductor layer are formed by a photolithography process. Specifically, a photosensitive conductive paste mainly containing Ag as a metal component is applied to the insulating layer by screen printing, thereby forming the photosensitive conductive paste layer. Then, ultraviolet rays or the like are irradiated to the photosensitive conductive paste layer through a photomask, and development is performed in an alkaline solution or the like. Thereby, the coil conductor layer and the external electrode conductor layer are formed on the insulating layer. At this time, the coil conductor layer and the external electrode conductor layer can be drawn as desired patterns through the photomask.

[0119] Further, a photosensitive insulating paste layer is formed on the insulating layer, and the insulating layer provided with the opening and the via hole is formed by a photolithography process. Specifically, a photosensitive insulating paste is applied to the insulating layer by screen printing, thereby forming the photosensitive insulating paste layer. Then, ultraviolet rays or the like are irradiated to the photosensitive insulating paste layer through a photomask, and development is performed in an alkaline solution or the like. At this time, the photosensitive insulating paste layer is subjected to pattern printing to provide the opening above the external electrode conductor layer and the via hole at the end portion of the coil conductor layer through the photomask, respectively.

[0120] After that, a photosensitive conductive paste layer is formed by applying on the insulating layer provided with the opening and the through hole, and a coil conductor layer and an external electrode conductor layer are formed by a photolithography process. Specifically, a photosensitive conductive paste with Ag as the main metal component is applied on the insulating layer by screen printing to fill the opening and the through hole, thereby forming the photosensitive conductive paste layer. Then, ultraviolet rays or the like are irradiated to the photosensitive conductive paste layer through a photomask, and development is performed in an alkaline solution or the like. Thus, the external electrode conductor layer connected to the external electrode conductor layer on the lower layer side through the opening, and the coil conductor layer connected to the coil conductor layer on the lower layer side through the through hole are formed on the insulating layer.

[0121] By repeatedly performing the above-mentioned process of forming the insulating layer, the coil conductor layer, and the external electrode conductor layer, a coil composed of the coil conductor layer formed on the plurality of insulating layers and an external electrode composed of the external electrode conductor layer formed on the plurality of insulating layers are formed. Also, the operation of applying the insulating paste on the insulating layer on which the coil and the external electrode are formed by screen printing is repeatedly performed, thereby forming the insulating layer. The insulating layer becomes an outer layer insulating layer located on the outer side of the coil conductor layer. Further, if a group of the coil and the external electrode is formed in a row and column shape on the insulating layer in the above process, a mother laminate can be obtained.

[0122] After that, the mother laminate is cut into a plurality of green laminates by cutting or the like. In the cutting process of the mother laminate, the external electrode is exposed from the mother laminate on the cut surface formed by cutting. At this time, if cutting misregistration of a predetermined amount or more occurs, the outer periphery of the coil conductor layer formed in the above process appears on the end surface or the bottom surface.

[0123] Then, the green laminate is fired under predetermined conditions to obtain a main body including the coil and the external electrode. The main body is subjected to roll grinding processing and polished to an appropriate outer dimension, and the portion of the external electrode exposed from the laminate is subjected to nickel plating with a thickness of 2 μm to 10 μm and tin plating with a thickness of 2 μm to 10 μm. By the above process, an inductor component of 0.4 mm x 0.2 mm x 0.2 mm is completed.

[0124] Further, the conductor pattern formation method is not limited to the above, and for example, a printing layering method in which a conductor paste is printed using a screen printing plate having an opening in the shape of the conductor pattern, a method in which a conductor film formed by a sputtering method or a vapor deposition method, a foil press welding, or the like is patterned by etching, a method in which, after a negative pattern is formed by a half-addition method and a conductor pattern is formed by plating, the excess portion is removed, and the like can be used. Further, by forming a multilayer conductor pattern, a high aspect ratio is achieved, and thus, a loss caused by resistance at a high frequency can be reduced. More specifically, a process in which the above-described conductor pattern formation process is repeated, a process in which a wiring formed in a half-addition process is repeatedly overlapped, a process in which, by a half-addition process, a part of a layer is formed, and for the other part, a film grown by plating is formed by etching, and the like can be used, and a process in which a wiring formed in a half-addition process is further grown in plating to achieve a high aspect ratio can be combined.

[0125] Further, the conductor material is not limited to the above-described Ag paste, and a good conductor such as Ag, Cu, Au, or the like formed by a sputtering method or a vapor deposition method, a foil press welding, plating, or the like can be used. Further, the insulating layer and the opening and via hole formation method are not limited to the above, and a method in which, after a press welding or a spin coating, a spray coating of an insulating material sheet, an opening is formed by laser or drilling processing, sand blasting processing, or the like can be used.

[0126] Further, as with the photolithography method, even if the laser or drilling processing, the sand blasting processing, or the like is used, the opening of the insulating layer is formed so that the inner diameter on the lower side in the stacking direction is smaller than the inner diameter on the upper side in the stacking direction. Thus, even in this case, the area of the first end surface of the via hole wiring on the lower side in the stacking direction is smaller than the area of the second end surface of the via hole wiring on the upper side in the stacking direction.

[0127] Further, the insulating material is not limited to the above-described glass or ceramic material, and an organic material such as an epoxy resin, a fluororesin, a high molecular resin, a composite material such as a glass epoxy resin, or the like can be used, but a material having a small dielectric constant and a small dielectric loss is desirable.

[0128] Further, the size of the inductor component is not limited to the above. Further, the external electrode formation method is not limited to a method in which plating processing is performed on an external conductor exposed by cutting, and a method in which, after cutting, an external electrode is further formed by dip coating of a conductor paste or a sputtering method, or the like, and plating processing is performed thereon can be used.

Claims

1. An inductive component, wherein, Possessing: a main body; a coil provided inside the main body and spirally wound along an axis; and a first external electrode and a second external electrode provided to the main body and electrically connected to the coil, the main body has a plurality of insulating layers laminated along the axis, the coil has a plurality of coil wirings laminated along the axis and a via wiring extending along the axis and connecting the coil wirings adjacent in the axis direction, the plurality of coil wirings are respectively wound along a plane, connected in series, and constitute a spiral, the plurality of coil wirings have a first coil wiring located at a most one-side in a direction parallel to the axis and connected to the first external electrode and a second coil wiring located at a most other-side in the direction parallel to the axis and connected to the second external electrode, an area of an end surface of the via wiring on the one-side in the direction parallel to the axis is smaller than an area of an end surface of the via wiring on the other-side in the direction parallel to the axis, a thickness of the second coil wiring in the direction parallel to the axis is greater than a thickness of the first coil wiring in the direction parallel to the axis, a line width of the second coil wiring is greater than a line width of the first coil wiring.

2. An inductive component, wherein, Possessing: a main body; a coil provided inside the main body and spirally wound along an axis; and a first external electrode and a second external electrode provided to the main body and electrically connected to the coil, the main body has a plurality of insulating layers laminated along the axis, the coil has a plurality of coil wirings laminated along the axis, the plurality of coil wirings are respectively wound along a plane, connected in series, and constitute a spiral, the coil wirings are constituted by one coil conductor layer or a plurality of coil conductor layers laminated along the axis and connected in parallel, the plurality of coil wirings have a first coil wiring located at a most one-side in a direction parallel to the axis and connected to the first external electrode and a second coil wiring located at a most other-side in the direction parallel to the axis and connected to the second external electrode, a number of the coil conductor layers constituting the second coil wiring is greater than a number of the coil conductor layers constituting the first coil wiring, a line width of the second coil wiring is greater than a line width of the first coil wiring.

3. The inductive component according to claim 2, wherein the coil has a via wiring extending along the axis and connecting the coil wirings adjacent in the axis direction, an area of an end surface of the via wiring on the one-side in the direction parallel to the axis is smaller than an area of an end surface of the via wiring on the other-side in the direction parallel to the axis.

4. The inductive component according to any one of claims 1 to 3, wherein The main body includes: first and second end surfaces facing each other; first and second side surfaces facing each other; a bottom surface connected between the first and second end surfaces and between the first and second side surfaces; and a top surface facing the bottom surface, The first external electrode is formed from the first end surface to the bottom surface, The second external electrode is formed from the second end surface to the bottom surface, The coil is wound along the axis in a manner that the axis is parallel to the bottom surface and the axis intersects the first and second side surfaces, The coil has: a winding portion wound in a spiral shape; a first lead-out portion connected between a first end of the winding portion and the first external electrode; and a second lead-out portion connected between a second end of the winding portion and the second external electrode, At least one of the first and second lead-out portions has, when viewed from a direction parallel to the axis, a horizontal line portion extending away from the winding portion in a direction parallel to the bottom surface at the top surface side of the winding portion, and a vertical line portion connected to the horizontal line portion and extending toward the bottom surface side in a direction orthogonal to the bottom surface.

5. The inductive device according to claim 4, wherein A shortest distance between the vertical line portion and the winding portion, when viewed from a direction parallel to the axis, is 1 / 2 or more of a line width of the coil wiring constituting the winding portion.

6. The inductive device according to any one of claims 1 to 3, wherein The second coil wiring has a first portion connected to the second external electrode, and a second portion other than the first portion, A line width of the first portion is larger than a line width of the second portion.

Images