Inductors

Abstract

The present invention provides an inductor having desired characteristics. The inductor has a coil (40) disposed in a component body (10). A first end of the coil (40) is connected to a first external electrode (20), and a second end of the coil (40) is connected to a second external electrode (30). The coil (40) includes: a plurality of coil conductor layers (41 to 48) disposed along a width direction W. Each coil conductor layer (41 to 48) is formed into a spiral shape (spiral shape) with a number of turns of more than one turn. The height dimension T1 of the component body (10) is greater than the width dimension W1 (T1>W1).

Description

[0001] This application is a divisional application of the application with application number “201811092536.5”, application date “September 19, 2018”, and invention name “Inductor” Technical Field

[0002] The present invention relates to an inductor. Background Art

[0003] Conventionally, electronic components are mounted on various electronic devices. As one example of such electronic components, a laminated inductor is known (see, for example, Patent Document 1).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2013-153009

[0005] However, with the increasing frequency of electronic devices such as mobile phones, there is a growing demand for compact inductors that can handle high-frequency signals. This miniaturization of inductors reduces their inductance (L value) and Q factor. Therefore, inductors used for high-frequency signals are being sought that exhibit improved inductance (L value), Q factor, and other characteristics.

[0006] However, for inductors like those disclosed in Patent Document 1, increasing the inductance requires increasing the number of coil conductor layers. Consequently, the laminate becomes larger in the stacking direction, increasing the mounting area of ​​the inductor. Furthermore, in inductors like those disclosed in Patent Document 1, increasing the number of turns of the coil conductor layer to one or more to increase the inductance reduces the area inside the coil conductor layer, resulting in a lower Q value. Summary of the Invention

[0007] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an inductor having desired characteristics.

[0008] An inductor according to one embodiment of the present invention comprises: a rectangular parallelepiped component body having a mounting surface through which a first external electrode and a second external electrode are exposed; and a coil disposed on the component body, with a first end connected to the first external electrode and a second end connected to the second external electrode, the coil comprising: a plurality of coil conductor layers arranged in a first direction parallel to the mounting surface and formed into a spiral shape having one or more turns on a plane perpendicular to the first direction; and a plurality of via conductor layers connecting the coil conductor layers adjacent to each other in the first direction, wherein the component body has a height dimension in a direction perpendicular to the mounting surface that is greater than a width dimension in the first direction.

[0009] According to this structure, compared to an inductor whose width dimension is smaller than its height dimension, the main surface area of ​​the multiple insulating layers stacked along the width direction of the component body is relatively large. Therefore, the outer diameter of the coil (coil conductor layer) can be made larger, and the length of the coil can be made longer. Therefore, the range of the inductor's inductance value (L value) can be expanded. In addition, the inner diameter of the spiral-shaped coil conductor layer can be made larger. Therefore, the Q value of the inductor is increased.

[0010] In the above-mentioned inductor, the component body preferably has a first end face and a second end face that are perpendicular to the mounting surface and parallel to the first direction; the first external electrode is embedded in the component body, formed in an L-shape, and is continuously exposed from the mounting surface to the first end face; and the second external electrode is embedded in the component body, formed in an L-shape, and is continuously exposed from the mounting surface to the second end face.

[0011] This structure can reduce the size of the inductor compared to a structure in which the external electrodes are externally mounted on the component body, and can also improve the efficiency of obtaining the inductance value of the inductor relative to the mounting area.

[0012] In the above-mentioned inductor, it is preferred that the above-mentioned multiple coil conductor layers respectively have: a spiral winding portion; and a via pad provided for connecting the above-mentioned via conductor layer. When viewed from the above-mentioned first direction, the above-mentioned winding portion includes: a portion along the annular outer peripheral track; a portion along the annular inner peripheral track that is closer to the inner side than the above-mentioned outer peripheral track; and a connecting portion connecting the portion of the above-mentioned outer peripheral track with the portion of the above-mentioned inner peripheral track. In the second direction perpendicular to the above-mentioned first end face, at least one of the multiple via pads provided in the portion of the above-mentioned winding portion along the above-mentioned outer peripheral track included in the above-mentioned coil is provided at a position that does not overlap with the above-mentioned first external electrode.

[0013] The first and second external electrodes embedded in the component body serve to reduce the outer diameter of the coil conductor layer. Conversely, in a second direction perpendicular to the first end face, at least one of the via pads is positioned so as not to overlap with the first (second) external electrode. This allows the winding portion of the coil conductor layer to be formed closer to the first (second) external electrode. Consequently, the outer diameter of the coil conductor layer can be increased.

[0014] In the above-mentioned inductor, it is preferred that the above-mentioned multiple coil conductor layers respectively have: a spiral winding portion; and a via pad provided for connecting the above-mentioned via conductor layer, and when viewed from the above-mentioned first direction, the above-mentioned winding portion includes: a portion along the annular outer peripheral track; a portion along the annular inner peripheral track that is closer to the inner side than the above-mentioned outer peripheral track; and a connecting portion connecting the portion of the above-mentioned outer peripheral track with the portion of the above-mentioned inner peripheral track, and the above-mentioned via pad is not formed in at least one of the first area and the second area, wherein the above-mentioned first area is an area in the above-mentioned first external electrode that overlaps with the above-mentioned first external electrode in a direction perpendicular to the above-mentioned first side surface and in a direction perpendicular to the above-mentioned mounting surface, and the above-mentioned second area is an area in the above-mentioned second external electrode that overlaps with the above-mentioned second external electrode in a direction perpendicular to the above-mentioned second side surface and in a direction perpendicular to the above-mentioned mounting surface.

[0015] The first and second external electrodes embedded in the component body serve to reduce the outer diameter of the coil conductor layer. In contrast, the lack of via pads in the first region allows the coil conductor layer's winding portion to be positioned closer to the first external electrode. Similarly, the lack of via pads in the second region allows the coil conductor layer's winding portion to be positioned closer to the second external electrode. Consequently, the outer diameter of the coil conductor layer can be increased.

[0016] In the above-mentioned inductor, it is preferred that the via pad connected to the winding portion of the outer track is formed to protrude outside the outer track, and the via pad connected to the winding portion of the inner track is formed to protrude inside the inner track.

[0017] With this structure, by forming the via pads of the outer track to protrude outward from the outer track, the outer diameter of the inner track's winding portion is increased. Furthermore, by forming the via pads of the inner track to protrude inward from the inner track, the outer diameter of the inner track's winding portion, i.e., the inner diameter of the winding portion, is increased. Consequently, the Q value of the inductor is increased.

[0018] In the above-mentioned inductor, the component body preferably includes: a plurality of insulating layers stacked along the first direction; the coil conductor layer is formed in a spiral shape on one main surface of the insulating layer; and the plurality of via-hole conductor layers are formed to penetrate the insulating layer in the thickness direction.

[0019] According to this structure, the component body can be easily formed by a plurality of insulating layers. Furthermore, a plurality of coil conductor layers can be connected by via-hole conductor layers penetrating the respective insulating layers, thereby easily forming a coil.

[0020] In the above-mentioned inductor, it is preferable that the insulating layer is a non-magnetic material.

[0021] According to this structure, an inductor suitable for high-frequency signals is obtained.

[0022] According to one aspect of the present invention, an inductor having desired characteristics can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a perspective view of an inductor according to one embodiment.

[0024] Figure 2 This is a perspective view showing the coil conductor layer and external electrodes of an inductor according to one embodiment.

[0025] Figure 3 This is an exploded perspective view of an inductor.

[0026] Figure 4 It is a plan view showing the insulator layer of the coil conductor layer and the external electrode layer.

[0027] Figure 5 This is an explanatory diagram of an inductor viewed from the stacking direction.

[0028] Description of Reference Numerals

[0029] 10…component body; 11…mounting surface; 20…first external electrode; 30…second external electrode; 40…coil; 41 to 48…coil conductor layers; T1…height dimension; W1…width dimension. DETAILED DESCRIPTION

[0030] Hereinafter, one embodiment will be described.

[0031] In addition, the drawings may sometimes show components enlarged for ease of understanding. The dimensional ratios of components may differ from the actual ones or from those in other drawings. In addition, in the cross-sectional views, hatching of some components may be omitted for ease of understanding.

[0032] like Figure 1 As shown, inductor 1 includes component body 10. Component body 10 is formed in a roughly rectangular parallelepiped shape. In this specification, "rectangular parallelepiped" includes cuboids with chamfered corners and edges, as well as cubes with rounded corners and edges. Furthermore, concavities and convexities may be formed partially or entirely on the main surfaces and side surfaces. Furthermore, the "rectangular parallelepiped" shape does not necessarily require the opposing surfaces to be completely parallel; they may be slightly tilted.

[0033] Component body 10 has a mounting surface 11. Mounting surface 11 is the surface that faces the circuit board when inductor 1 is mounted on the circuit board. Component body 10 has an upper surface 12 parallel to mounting surface 11. Component body 10 also has two pairs of surfaces perpendicular to mounting surface 11. One pair of these two pairs of surfaces is defined as a first side surface 13 and a second side surface 14, and the other pair of these two pairs of surfaces is defined as a first end surface 15 and a second end surface 16.

[0034] In this specification, the direction perpendicular to the upper surface 12 and the mounting surface 11 is referred to as the "height direction", the direction perpendicular to the first side surface 13 and the second side surface 14 is referred to as the "width direction", and the direction perpendicular to the first end surface 15 and the second end surface 16 is referred to as the "length direction". As a specific example, Figure 1 The figure shows "longitudinal direction L", "height direction T", and "width direction W". The size in the "width direction" is referred to as "width dimension", the size in the "height direction" is referred to as "height dimension", and the size in the "longitudinal direction" is referred to as "length dimension".

[0035] In the component body 10, the size of the length direction L (length dimension L1) is preferably greater than 0 mm and less than 1.0 mm. For example, the length dimension L1 is 0.6 mm. In addition, in the component body 10, the size of the width direction W (width dimension W1) is preferably greater than 0 mm and less than 0.6 mm. The width dimension W1 is preferably less than 0.36 mm, and more preferably less than 0.33 mm. For example, the width dimension W1 of the component body 10 is 0.3 mm. In addition, in the component body 10, the size of the height direction T (height dimension T1) is preferably greater than 0 mm and less than 0.8 mm. For example, the height dimension T1 of the component body 10 is 0.4 mm. In the present embodiment, for the component body 10, the height dimension T1 is larger than the width dimension W1 (T1>W1).

[0036] Inductor 1 includes a first external electrode 20 and a second external electrode 30 exposed on the surface of component body 10. First external electrode 20 is exposed on mounting surface 11 of component body 10. Furthermore, first external electrode 20 is exposed on first end surface 15 of component body 10. Second external electrode 30 is exposed on mounting surface 11 of component body 10. Furthermore, second external electrode 30 is exposed on second end surface 16 of component body 10. In other words, first external electrode 20 and second external electrode 30 are exposed on mounting surface 11. In other words, the surface of component body 10 where first external electrode 20 and second external electrode 30 are exposed is mounting surface 11.

[0037] On the first end surface 15, the first external electrode 20 is formed to a length approximately two-thirds of the height of the component body 10, as measured from the mounting surface 11 of the component body 10. In the width direction W, the first external electrode 20 is formed approximately in the center of the component body 10, with the width dimension of the first external electrode 20 being smaller than the width dimension of the component body 10. On the second end surface 16, the second external electrode 30 is formed to a length approximately two-thirds of the height of the component body 10, as measured from the mounting surface 11 of the component body 10. In this embodiment, the second external electrode 30 is formed approximately in the center of the component body 10, with the width dimension of the second external electrode 30 being smaller than the width dimension of the component body 10. Alternatively, the width dimension of the second external electrode 30 may be equal to the width dimension of the component body 10.

[0038] like Figure 2 As shown in FIG, the inductor 1 includes a coil 40 provided in the component body 10. A first end of the coil 40 is connected to the first external electrode 20, and a second end of the coil 40 is connected to the second external electrode 30. Figure 2 In FIG. 1 , the component body 10 is indicated by a two-dot chain line so that the coil 40 and the first external electrode 20 and the second external electrode 30 can be easily distinguished.

[0039] The first external electrode 20 is formed in an L-shape. The first external electrode 20 includes an end surface electrode 20a exposed on the first end surface 15 of the component body 10 and a lower surface electrode 20b exposed on the mounting surface 11 of the component body 10. In other words, the first external electrode 20 is continuously exposed on the component body 10 from the mounting surface 11 to the first end surface 15.

[0040] The second external electrode 30 is formed in an L-shape. The second external electrode 30 includes an end surface electrode 30a exposed on the second end surface 16 of the component body 10 and a lower surface electrode 30b exposed on the mounting surface 11 of the component body 10. In other words, the second external electrode 30 is continuously exposed on the component body 10 from the mounting surface 11 to the second end surface 16.

[0041] Furthermore, as an inductor, it is also possible to design a covering layer that covers the first external electrode 20 and the second external electrode 30. As the material of the covering layer, a material with high solder resistance and solder wettability can be used. For example, metals such as nickel (Ni), copper (Cu), tin (Sn), gold (Au), or alloys containing these metals can be used. In addition, the covering layer can also be formed by multiple layers. For example, the covering layer includes: Ni plating that covers the first external electrode 20 and the second external electrode 30; and Sn plating that covers the surface of the Ni plating. The covering layer prevents oxidation of the surfaces of the first external electrode 20 and the second external electrode 30. The covering layer may protrude from the component body 10, or may form the same surface as each surface of the component body 10.

[0042] like Figure 2 As shown, the first external electrode 20 includes: a plurality of external conductor layers 21-28 arranged in the width direction W. The plurality of external conductor layers 21-28 are connected to each other along the width direction W to form a single first external electrode 20. Similarly, the second external electrode 30 includes: a plurality of external conductor layers 31-38 arranged in the width direction W. These plurality of external conductor layers 31-38 are connected to each other in the width direction W to form a single second external electrode 30. The external conductor layers 21-28 and 31-38 do not need to be in contact with each other along the width direction; they can also be connected using slightly smaller layers or vias, or they can be completely non-contact. The coil 40 includes: a plurality of coil conductor layers 41-48 arranged in the width direction W. The plurality of coil conductor layers 41-48 are connected by via conductor layers described later to form the coil 40.

[0043] like Figure 3 As shown, the component body 10 includes a plurality of insulating layers 60. In the present embodiment, when the plurality of insulating layers are not distinguished, the figure mark "60" is used. When the plurality of insulating layers are distinguished one by one, the figure marks "61, 62, 63a to 63h, 64, 65" are used. The plurality of insulating layers 60 are each formed in a rectangular plate shape. The component body 10 is formed into a rectangular parallelepiped by the stacked insulating layers 60. As the material of the insulating layer 60, a non-magnetic material can be used. In addition, as the material of the insulating layer 60, a magnetic material can also be used. The insulating layer 60 is composed of materials such as an insulating material with borosilicate glass as the main component, an insulating resin such as aluminum oxide, zirconium oxide, or a polyimide resin. In addition, the interface between the plurality of insulating layers 60 of the component body 10 is sometimes unclear due to treatments such as firing and curing.

[0044] The colors of the insulating layers 61 and 65 are different from the colors of the other insulating layers 62 , 63 a to 63 h , and 64 . Figure 1 In the figure, the insulator layers 61 and 65 are shown as distinct from the other insulator layers using hatching and solid lines. This allows detection of lateral rolling, etc., during inductor 1 mounting. Furthermore, the insulator layers 61 and 65 can be the same color as the other insulator layers 62, 63a to 63h, and 64. If the length L1, width W1, and height T1 are different values, lateral rolling, etc., can be detected even if the colors are the same as described above.

[0045] like Figure 3 and Figure 4As shown, the coil 40 includes: a plurality of coil conductor layers 41 to 48; and via conductor layers 51 to 57 connecting the coil conductor layers 41 to 48. Each coil conductor layer 41 to 48 is wound in a planar shape on the insulating layer 63a to 63h. Each coil conductor layer 41 to 48 is formed into a spiral shape (spiral shape) with more than one turn. In addition, Figure 4 In FIG. 1 , the outer shape of the insulating layer 60 ( 63 a to 63 h ) is shown by two-dot chain lines.

[0046] like Figure 4 As shown, the coil conductor layers 41 to 48 of this embodiment are formed in a spiral shape substantially along two annular orbits R1 and R2. Therefore, the number of turns of the coil conductor layers 41 to 48 of this embodiment is 1 or more and less than 2 turns.

[0047] The via hole conductor layers 51 to 57 are formed by penetrating the insulating layers 63b to 63h in the thickness direction. Figure 3 In FIG, the via hole conductor layers 51 to 57 are shown as single dot chain lines between the coil conductor layers 41 to 48. Figure 4 In FIG. 5 , the via-hole conductor layers 51 to 57 are indicated by dotted lines, and the connection destinations of these via-hole conductor layers 51 to 57 are indicated by dashed lines.

[0048] like Figure 2 As shown, the first external electrode 20 includes a plurality of external conductor layers 21 to 28. In addition, the second external electrode 30 includes a plurality of external conductor layers 31 to 38.

[0049] The outer conductor layers 21 to 28, 31 to 38 are provided on the respective insulating layers 63a to 63h. The outer conductor layers 21 to 28, 31 to 38 are formed in an L shape. The outer conductor layers 22 to 28, 32 to 38 penetrate the insulating layers 63b to 63h in the thickness direction. Figure 2 As shown, the outer conductor layers 21 to 28 are connected to each other through the insulating layers 63a to 63h to form the L-shaped first outer electrode 20. Figure 2 As shown, the outer conductor layers 31 to 38 are connected to each other via the insulating layers 63 a to 63 h to form the L-shaped second outer electrode 30 .

[0050] Each coil conductor layer 41-48 and via conductor layers 51-57 is formed of a conductive material such as a metal with low electrical resistance, such as silver (Ag), copper (Cu), or gold (Au), or an alloy primarily composed of these metals. Each outer conductor layer 21-28 and 31-38 is formed of a conductive material such as a metal with low electrical resistance, such as silver (Ag), copper (Cu), or gold (Au), or an alloy primarily composed of these metals.

[0051] exist Figure 4, the coil conductor layers 41 to 48 of the respective insulating layers 63a to 63h will be described in order from the upper left.

[0052] In the insulator layer 63a, the coil conductor layer 41 includes a winding portion 41L spirally extending from the outer track R1 to the inner track R2, and a via pad 41P formed at the second end of the winding portion 41L. Specifically, the winding portion 41L includes a portion along the outer track R1, a portion along the inner track R2, and a connecting portion between the outer track R1 and the inner track R2. The first end of the winding portion 41L is connected to the upper end of the outer conductor layer 21 of the first external electrode 20.

[0053] In the insulator layer 63b, the coil conductor layer 42 includes a spirally wound portion 42L extending from the inner track R2 to the outer track R1, and via pads 42P (42Pa, 42Pb) formed at both ends of the wound portion 42L. Similar to the coil conductor layer 41, the coil conductor layer 42 has portions extending along the outer track R1 and inner track R2, and connecting portions connecting these portions. The via pads 42Pa are connected to the via pads 41P of the insulator layer 63a via the via conductor layer 51 of the insulator layer 63b.

[0054] In the insulator layer 63c, the coil conductor layer 43 includes a spirally wound portion 43L extending from the outer track R1 to the inner track R2, and via pads 43P (43Pa, 43Pb) formed at both ends of the wound portion 43L. Similar to the coil conductor layer 41, the coil conductor layer 43 has portions extending along the outer track R1 and inner track R2, and connecting portions connecting these portions. The via pads 43Pa are connected to the via pads 43Pb ​​on the insulator layer 63b via the via conductor layer 52 on the insulator layer 63c.

[0055] In the insulator layer 63d, the coil conductor layer 44 includes a spirally wound portion 44L extending from the inner circumferential track R2 to the outer circumferential track R1, and via pads 44P (44Pa, 44Pb) formed at both ends of the wound portion 44L. Similar to the coil conductor layer 41, the coil conductor layer 44 has portions extending along the outer circumferential track R1 and the inner circumferential track R2, and connecting portions connecting these portions. Furthermore, the coil conductor layer 44 includes via pads 44Pc formed symmetrically with the via pads 44Pb. The via pads 44Pa are connected to the via pads 43Pb ​​of the insulator layer 63c via the via conductor layer 53 of the insulator layer 63d.

[0056] In the insulator layer 63e, the coil conductor layer 45 includes: a winding portion 45L formed in a spiral shape from the outer peripheral track R1 to the inner peripheral track R2; and via pads 45P (45Pa, 45Pb) formed at both ends of the winding portion 45L. Similar to the coil conductor layer 41, the coil conductor layer 45 has: portions along the outer peripheral track R1 and the inner peripheral track R2; and connecting portions connecting these portions. In addition, the coil conductor layer 45 includes: via pads 45Pc formed in a position symmetrical to the via pads 45P. The via pads 45Pa and 45Pc are connected to the via pads 44Pc and 44Pb of the insulator layer 63d via the via conductor layer 54 (54a, 54b) of the insulator layer 63e.

[0057] In the insulator layer 63f, the coil conductor layer 46 includes a spirally wound portion 46L extending from the inner track R2 to the outer track R1, and via pads 46Pa and 46Pb formed at both ends of the wound portion 46L. Similar to the coil conductor layer 41, the coil conductor layer 46 has portions extending along the outer track R1 and inner track R2, and connecting portions connecting these portions. The via pad 46Pa is connected to the via pad 45Pb on the insulator layer 63e via the via conductor layer 55 on the insulator layer 63f.

[0058] In the insulator layer 63g, the coil conductor layer 47 includes a spirally wound portion 47L extending from the outer track R1 to the inner track R2, and via pads 47P (47Pa, 47Pb) formed at both ends of the wound portion 47L. Similar to the coil conductor layer 41, the coil conductor layer 47 has portions extending along the outer track R1 and inner track R2, and connecting portions connecting these portions. The via pads 47Pa are connected to the via pads 46Pb of the insulator layer 63f via the via conductor layer 56 of the insulator layer 63g.

[0059] In the insulator layer 63h, the coil conductor layer 48 includes a spirally wound portion 48L extending from the inner track R2 to the outer track R1, and a via pad 48P formed at the first end of the wound portion 48L. Similar to the coil conductor layer 41, the coil conductor layer 48 has portions extending along the outer track R1 and inner track R2, and a connecting portion connecting these portions. The second end of the wound portion 48L is connected to the upper end of the outer conductor layer 38 of the second outer electrode 30. The via pad 48P is connected to the via pad 47Pb of the insulator layer 63g via the via conductor layer 57 of the insulator layer 63h.

[0060] Each via pad 41P-48P is formed to have an outer diameter greater than the line width of the winding portions 41L-48L. Each via pad 41P-48P is formed, for example, in a circular shape, with a diameter greater than the line width of the winding portions 41L-48L. Furthermore, each via pad 41P-48P may have a shape other than a circle, such as a polygonal shape, a semicircular shape, an elliptical shape, or a combination of these shapes.

[0061] (Manufacturing Method)

[0062] Next, refer to Figure 3 A method for manufacturing the above-mentioned inductor 1 will be described.

[0063] First, a mother insulator layer that will become the insulator layer 61 is formed. The mother insulator layer is a larger insulator layer in which multiple insulator layers 61 are arranged in a matrix in a connected state. After an insulating paste containing borosilicate glass as a main component is applied to a carrier film of, for example, an 8-inch square size by screen printing, the entire insulating paste is exposed to ultraviolet light. As a result, the insulating paste is cured to form the mother insulator layer that will become the insulator layer 61. In this embodiment, an insulating paste having a relative magnetic permeability of "2" or less after firing is used. In addition, the insulating paste used for the insulator layer 61 is colored differently from the insulating paste used to become the insulating layers 62, 63a to 63h, and 64.

[0064] Next, a mother insulating layer to become insulating layer 62 is formed. After insulating paste is applied to the mother insulating layer to become insulating layer 61 by screen printing, the entire insulating paste is exposed to ultraviolet light to form the mother insulating layer to become insulating layer 62.

[0065] Next, a mother insulating layer to become the insulating layer 63a is formed. After insulating paste is applied to the mother insulating layer to become the insulating layer 62, the entire insulating paste is exposed to ultraviolet light to form the mother insulating layer to become the insulating layer 63a.

[0066] Next, the coil conductor layer 41 and the outer conductor layers 21 and 31 are formed through a photolithography process. For example, a photosensitive conductive paste containing Ag as the main metal component is printed and applied to the mother insulator layer that will become the insulator layer 63a. This forms the conductive paste layer. Next, the conductive paste layer is irradiated with ultraviolet light or the like through a photomask and developed with an alkaline solution or the like. Thus, the coil conductor layer 41 and the outer conductor layers 21 and 31 are formed on the mother insulator layer that will become the insulator layer 63a.

[0067] Next, a mother insulator layer, which will become insulating layer 63b, is formed. After applying an insulating paste to the mother insulator layer, which will become insulating layer 63a, the insulating paste is exposed to ultraviolet light through a photomask that covers the locations where the via-hole conductor layer 51 and the outer conductor layers 22 and 32 will be formed. The uncured insulating paste is then removed using an alkaline solution or the like. This forms the mother insulator layer, which will become insulating layer 63b. This mother insulator layer has through-holes at positions corresponding to the via-hole pads 41P of the coil conductor layer 41 and has partially cut away the corners corresponding to the outer conductor layers 22 and 32.

[0068] Next, a photolithography process is used to form the coil conductor layer 42, the via conductor layer 51, and the outer conductor layers 22 and 32. Similar to the coil conductor layer 41 described above, a photosensitive conductive paste is applied to form a conductive paste layer on the mother insulator layer, which will become the insulator layer 63b. At this point, the conductive paste fills the through-holes and notches described above. Next, the conductive paste layer is irradiated with ultraviolet light or the like through a photomask and developed using an alkaline solution or the like. Thus, the coil conductor layer 42, the via conductor layer 51, and the outer conductor layers 22 and 32 are formed on the mother insulator layer, which will become the insulator layer 63b.

[0069] Thereafter, by alternately repeating the process of forming a mother insulator layer and the photolithography process, mother insulator layers to become insulator layers 63c to 63h, coil conductor layers 42 to 48, external conductor layers 23 to 28 and 33 to 38, and via-hole conductor layers 52 to 57 are formed.

[0070] Next, similarly to the mother insulator layer that became insulator layer 62, a mother insulator layer that will become insulator layer 64 is formed on the mother insulator layer that will become insulator layer 63h. Furthermore, similarly to the mother insulator layer that became insulator layer 61, a mother insulator layer that will become insulator layer 65 is formed on the mother insulator layer that will become insulator layer 64.

[0071] Through the above steps, a mother laminated body including a plurality of component bodies 10 arranged in a matrix and connected to each other is obtained.

[0072] Next, the mother laminate is cut using a cutter or the like to obtain an unfired component body 10. During the cutting step, the outer conductor layers 21 to 28 and 31 to 38 are exposed from the component body 10 on the cut surfaces formed by the cutting. Furthermore, the component body 10 shrinks during the firing process described later, so the mother laminate is cut to take this shrinkage into account.

[0073] Next, the unfired component body 10 is fired under predetermined conditions to obtain the component body 10. Furthermore, the component body 10 is subjected to barrel polishing.

[0074] In the case of an inductor including a covering layer, after barrel polishing, the covering layer is formed to cover the outer conductive layers 21 to 28 and 31 to 38. For example, the covering layer can be formed by electroplating or chemical plating.

[0075] The inductor 1 is completed through the above steps.

[0076] The above-described manufacturing method is merely illustrative and can be replaced or supplemented by other known manufacturing methods as long as the structure of inductor 1 can be achieved. For example, a mother insulator layer, which will serve as each insulating layer, can be formed on a carrier film, and a coil conductor layer can be formed on the desired mother insulator layer. Alternatively, the mother laminate can be obtained by stacking multiple mother insulator layers. Furthermore, the coil conductor layer can be formed using other methods such as printing.

[0077] (effect)

[0078] Next, the operation of the above-mentioned inductor 1 will be described.

[0079] like Figure 1 As shown in FIG. 1 , the component body 10 of the inductor 1 is in the shape of a rectangular parallelepiped and has a mounting surface 11 that exposes the first external electrode 20 and the second external electrode 30. Figure 2 As shown, inductor 1 includes a coil 40 disposed within component body 10. A first end of coil 40 is connected to first external electrode 20, and a second end of coil 40 is connected to second external electrode 30. Coil 40 includes multiple coil conductor layers 41-48 arranged in width direction W. Each coil conductor layer 41-48 is formed in a spiral shape with one or more turns. Component body 10 has a height dimension T1 that is greater than its width dimension W1 (T1>W1).

[0080] Compared to an inductor whose width dimension W1 is less than or equal to its height dimension T1, the main surface area of ​​the multiple insulating layers 61, 62, 63a to 63h, 64, and 65 stacked in the width direction W is relatively large. Consequently, the outer diameter of coil 40 (coil conductor layers 41 to 48) can be increased, and the length of coil 40 can be made longer. Consequently, the inductor 1 can have a wider range of inductance values ​​(L values). Furthermore, the inner diameter of the spiral-shaped coil conductor layers 41 to 48 can be increased, resulting in a higher Q value for inductor 1.

[0081] like Figure 4As shown, each coil conductor layer 41-48 has: a winding portion 41L-48L formed in a spiral shape on the outer peripheral track R1 and the inner peripheral track R2; and a via pad 41P-48P that connects the via conductor layers 51-57. Each via pad 41P-48P is formed with an outer diameter larger than the line width of the winding portion 41L-48L. Each via pad 41P-48P forms a suitable coil 40. From the perspective of reducing the resistance value of the coil 40, the via conductor layers 51-57 are preferably thicker. In addition, from the perspective of connectivity between the via conductor layers 51-57 and the coil conductor layers 41-48, the via conductor layers 51-57 are preferably thicker.

[0082] Each insulator layer 63a-63h is formed by applying an insulating paste using screen printing. The coil conductor layers 41-48 and the via conductor layers 51-57 are formed by photolithography using a photosensitive conductive paste. Considering manufacturing process misalignment, the size of the via conductor layers 51-57 requires larger via pads 41P-48P.

[0083] like Figure 5 As shown, the first and second external electrodes 20, 30 of the inductor 1 are formed in an L-shape. Furthermore, no via pads are formed in the first region A1 of the first external electrode 20, which overlaps with the first external electrode 20 in a direction perpendicular to the first end face 15 and the mounting surface 11. Furthermore, no via pads are formed in the second region A2 of the second external electrode 30, which overlaps with the second external electrode 30 in a direction perpendicular to the second end face 16 and the mounting surface 11. If a via pad were formed in the first region A1, it would be necessary to separate the via pad from the first external electrode 20 to prevent short circuits and parasitic capacitance between the via pad and the first external electrode 20. This separation reduces the outer diameters of the winding portions 41L to 48L of the coil conductor layers 41 to 48. Similarly, when a via pad is formed in the second area A2, it is necessary to separate the via pad from the second external electrode 30 to prevent short circuits and parasitic capacitance between the via pad and the second external electrode 30. In response to this separation, the outer diameters of the winding portions 41L-48L of the coil conductor layers 41-48 are reduced.

[0084] Therefore, as in this embodiment, since no via pads are formed in the first area A1, the winding portions 41L to 48L of the coil conductor layers 41 to 48 can be formed close to the first external electrode 20. Similarly, since no via pads are formed in the second area A2, the winding portions 41L to 48L of the coil conductor layers 41 to 48 can be formed close to the second external electrode 30. Consequently, the outer diameters of the coil conductor layers 41 to 48 can be increased.

[0085] On the other hand, if the via pads are formed in the first and second areas A1 and A2, and the outer diameter of the coil conductor layers 41 to 48 is increased, the via pads are formed inside the outer peripheral track R1 of the coil conductor layers 41 to 48. This reduces the outer diameter of the inner peripheral track R2. In other words, the length of the coil 40 can be shortened.

[0086] In contrast, as in this embodiment, no via pads are formed in the first area A1; in other words, the via pads are formed at a position that does not overlap with the first external electrode 20. This allows the outer diameter of the inner track R2, or in other words, the inner diameter of the inner track R2, to be increased. Similarly, no via pads are formed in the second area A2; in other words, the via pads are formed at a position that does not overlap with the second external electrode 30. This allows the outer diameter of the inner track R2, or in other words, the inner diameter of the inner track R2, to be increased. By increasing the inner diameter of the inner track R2, the Q factor of the inductor 1 is increased.

[0087] Furthermore, the via pads connected to the winding portion of outer rail R1 are formed to protrude outward from outer rail R1, while the via pads connected to the winding portion of inner rail R2 are formed to protrude inward from inner rail R2. By making the via pads of outer rail R1 protrude outward from outer rail R1, the outer diameter of the winding portion of inner rail R2 is increased. Furthermore, by making the via pads of inner rail R2 protrude inward from inner rail R2, the outer diameter of the winding portion of inner rail R2, or in other words, the inner diameter of the winding portion, is increased. This increases the Q value of the inductor.

[0088] As described above, according to this embodiment, the following effects are achieved.

[0089] (1) The component body 10 of the inductor 1 is rectangular and has a mounting surface 11 that exposes the first external electrode 20 and the second external electrode 30. The inductor 1 includes a coil 40 disposed within the component body 10. The first end of the coil 40 is connected to the first external electrode 20, and the second end of the coil 40 is connected to the second external electrode 30. The coil 40 includes a plurality of coil conductor layers 41 to 48 arranged in the width direction W. Each coil conductor layer 41 to 48 is formed into a spiral shape with one or more turns. The component body 10 has a height dimension T1 that is larger than a width dimension W1 (T1>W1).

[0090] Compared to an inductor whose width dimension W1 is less than or equal to its height dimension T1, the main surface area of ​​the multiple insulating layers 61, 62, 63a to 63h, 64, and 65 stacked in the width direction W is relatively large. This allows the outer diameter of coil 40 (coil conductor layers 41 to 48) to be increased, and the length of coil 40 to be lengthened. Consequently, the inductor 1 can have a wider range of inductance values ​​(L values). Furthermore, the inner diameter of the spiral-shaped coil conductor layers 41 to 48 can be increased, thereby increasing the Q value of inductor 1.

[0091] (2) The first and second external electrodes 20 and 30 are formed in an L-shape and embedded in the component body 10. This allows for a more compact inductor 1 compared to a structure where the external electrodes are externally mounted on the component body. Furthermore, the efficiency with which the inductance value can be obtained relative to the mounting area of ​​the inductor 1 can be improved.

[0092] (3) The first and second external electrodes 20 and 30 are not formed on the upper surface 12 or on the upper surface 12 side of the first and second end surfaces 15 and 16. Therefore, the magnetic flux generated near these locations is not blocked, which increases the Q value of the inductor 1. Furthermore, the first and second external electrodes 20 and 30 are formed on the first and second end surfaces 15 and 16, respectively, to a length approximately two-thirds of the height of the component body 10 from the mounting surface 11, thereby ensuring a secure fixing force to the substrate during mounting.

[0093] (4) The plurality of coil conductor layers 41 to 48 each include spirally wound portions 41L to 48L and via pads 41P to 48P provided to connect the via conductor layers 51 to 57. The wound portions 41L to 48L include a portion along the annular outer track R1, a portion along the annular inner track R2 located inward of the outer track R1, and a connecting portion connecting the outer track R1 portion to the inner track R2 portion. A via pad is not formed in at least one of the first region A1 that overlaps with the first external electrode 20 in a direction perpendicular to the first end face 15 and in a direction perpendicular to the mounting surface 11, and the second region A2 that overlaps with the second external electrode 30 in a direction perpendicular to the second end face 16 and in a direction perpendicular to the mounting surface 11.

[0094] The first and second external electrodes 20, 30 embedded in the component body 10 serve to reduce the outer diameter of the coil conductor layers 41 to 48. In contrast, at least one of the via pads is positioned so as not to overlap with the first external electrode 20 (second external electrode) in a direction perpendicular to the first end face 15 (second end face 16). Consequently, the winding portions 41L to 48L of the coil conductor layers can be formed closer to the first external electrode 20 (second external electrode 30). Consequently, the outer diameter of the coil conductor layers 41 to 48 can be increased.

[0095] Furthermore, the via pads 41P to 48P are preferably provided at positions that do not overlap with the first external electrode 20 (second external electrode 30) in a direction perpendicular to the first end surface 15 (second end surface 16).

[0096] (5) The via pad connected to the winding portion of the outer rail R1 is formed to protrude outward from the outer rail R1, and the via pad connected to the winding portion of the inner rail R2 is formed to protrude inward from the inner rail R2. By forming the via pad of the outer rail R1 to protrude outward from the outer rail R1, the outer diameter of the winding portion of the inner rail R2 is increased. In addition, by forming the via pad of the inner rail R2 to protrude inward from the inner rail R2, the outer diameter of the winding portion of the inner rail R2, in other words, the inner diameter of the winding portion, can be increased. Therefore, the Q value of the inductor can be increased.

[0097] (6) Component body 10 includes multiple stacked insulator layers 61, 62, 63a to 63h, 64, and 65. Coil conductor layers 41 to 48 are formed in a spiral pattern on one main surface of insulator layers 63a to 63h. Multiple via conductor layers 51 to 57 are formed by penetrating insulator layers 63b to 63h in the thickness direction. Therefore, component body 10 is easily formed by multiple insulator layers 61, 62, 63a to 63h, 64, and 65. Furthermore, coil 40 can be easily formed by connecting multiple coil conductor layers 41 to 48 via via conductor layers 51 to 57 penetrating insulator layers 63b to 63h.

[0098] (7) The insulating layers 61, 62, 63a to 63h, 64, and 65 are non-magnetic. Therefore, the inductor 1 suitable for high-frequency signals is obtained.

[0099] (8) The component body 10 preferably has a greater height than width. This allows the height of the first external electrode 20 on the first end surface 15 to be set higher relative to a given mounting area, thereby improving the fixing force. Similarly, the height of the second external electrode 30 on the second end surface 16 can be set higher relative to a given mounting area, thereby improving the fixing force.

[0100] In addition, the above-mentioned embodiment can also be implemented in the following manner.

[0101] Regarding the above-mentioned embodiment, the number of turns of the coil conductor layer may be changed as appropriate. In addition, a single inductor may include a coil including coil conductor layers having different numbers of turns.

[0102] In the above embodiment, the first external electrode 20 and the second external electrode 30 may be formed on the surface (outside) of the component body 10. Such electrodes can be formed on the ends of the coil conductor layer exposed from the component body 10 by plating, sputtering, coating and firing, etc.

[0103] The shape of the coil 40 (shape of the outer orbit R1 and inner orbit R2 ), line width, line length, etc. may be appropriately changed in the above embodiment. Also, the shape of the first external electrode 20 and the second external electrode 30 may be appropriately changed.

Claims

1. An inductor, characterized in that: have: A rectangular parallelepiped component body having a mounting surface on which the first external electrode and the second external electrode are exposed; and a coil, which is disposed on the component body and has a first end connected to the first external electrode and a second end connected to the second external electrode, The coil includes: a plurality of coil conductor layers arranged in a first direction parallel to the mounting surface and formed in a spiral shape on a plane perpendicular to the first direction; and a plurality of via conductor layers connecting the coil conductor layers adjacent to each other in the first direction. The component body has a first end surface and a second end surface which are orthogonal to the mounting surface and parallel to the first direction. The first external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the first end surface. The second external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the second end surface. The plurality of coil conductor layers each include: a spiral winding portion; and a via pad provided to connect the via conductor layers. When viewed from the first direction, the winding portion includes: a portion along the annular outer peripheral track; a portion along the annular inner peripheral track that is closer to the inner side than the outer peripheral track; and a connecting portion connecting the outer peripheral track portion and the inner peripheral track portion. The via pad is not formed in at least one of a first region of the first external electrode that overlaps with the first external electrode in a direction perpendicular to the first end surface and in a direction perpendicular to the mounting surface and a second region of the second external electrode that overlaps with the second external electrode in a direction perpendicular to the second end surface and in a direction perpendicular to the mounting surface, The via pad connected to the winding portion of the outer peripheral track is formed to protrude to the outside of the outer peripheral track, The via pad connected to the winding portion of the inner circumferential track is formed to protrude toward the inner side of the inner circumferential track. In a second direction perpendicular to the first end face, a via pad provided on a portion of the winding portion included in the coil along the inner circumferential track is provided at a position at least partially overlapping with the first external electrode and the second external electrode, and is provided outside the first region and the second region.

2. An inductor, characterized in that: have: A rectangular parallelepiped component body having a mounting surface on which the first external electrode and the second external electrode are exposed; and a coil, which is disposed on the component body and has a first end connected to the first external electrode and a second end connected to the second external electrode, The coil includes: a plurality of coil conductor layers arranged in a first direction parallel to the mounting surface and formed in a spiral shape on a plane perpendicular to the first direction; and a plurality of via conductor layers connecting the coil conductor layers adjacent to each other in the first direction. The component body has a first end surface and a second end surface which are orthogonal to the mounting surface and parallel to the first direction. The first external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the first end surface. The second external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the second end surface. The plurality of coil conductor layers each include: a spiral winding portion; and a via pad provided to connect the via conductor layers. When viewed from the first direction, the winding portion includes: a portion along the annular outer peripheral track; a portion along the annular inner peripheral track that is closer to the inner side than the outer peripheral track; and a connecting portion connecting the outer peripheral track portion and the inner peripheral track portion. At least one of the plurality of via pads provided on a portion of the winding portion included in the coil along the outer peripheral track is provided at a position that does not overlap with the first external electrode in a second direction perpendicular to the first end surface, The via pad connected to the winding portion of the outer peripheral track is formed to protrude to the outside of the outer peripheral track, The via pad connected to the winding portion of the inner circumferential track is formed to protrude toward the inner side of the inner circumferential track. A first region overlapping the first external electrode in a direction perpendicular to the first end surface and in a direction perpendicular to the mounting surface is formed in the first external electrode, and a second region overlapping the second external electrode in a direction perpendicular to the second end surface and in a direction perpendicular to the mounting surface is formed in the second external electrode, In a second direction perpendicular to the first end face, a via pad provided on a portion of the winding portion included in the coil along the inner circumferential track is provided at a position at least partially overlapping with the first external electrode and the second external electrode, and is provided outside the first region and the second region.

3. An inductor, characterized in that: have: A rectangular parallelepiped component body having a mounting surface on which the first external electrode and the second external electrode are exposed; and a coil, which is disposed on the component body and has a first end connected to the first external electrode and a second end connected to the second external electrode, The coil includes: a plurality of coil conductor layers arranged in a first direction parallel to the mounting surface and formed in a spiral shape on a plane perpendicular to the first direction; and a plurality of via conductor layers connecting the coil conductor layers adjacent to each other in the first direction. The component body has a first end surface and a second end surface which are orthogonal to the mounting surface and parallel to the first direction. The first external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the first end surface. The second external electrode is embedded in the component body and formed in an L shape, and is continuously exposed from the mounting surface to the second end surface. The plurality of coil conductor layers each include: a spiral winding portion; and a via pad provided to connect the via conductor layers. When viewed from the first direction, the winding portion includes: a portion along the annular outer peripheral track; a portion along the annular inner peripheral track that is closer to the inner side than the outer peripheral track; and a connecting portion connecting the outer peripheral track portion and the inner peripheral track portion. At least one of the plurality of via pads provided on a portion of the winding portion included in the coil along the outer peripheral track is provided at a position that does not overlap with the first external electrode in a second direction perpendicular to the first end surface, At least one of the plurality of via pads provided on a portion of the winding portion included in the coil along the inner circumferential track is provided at a position that does not at least partially overlap with the first external electrode in a second direction perpendicular to the first end surface, The via pad connected to the winding portion of the outer peripheral track is formed to protrude to the outside of the outer peripheral track, The via pad connected to the winding portion of the inner circumferential track is formed to protrude toward the inner side of the inner circumferential track. A first region overlapping the first external electrode in a direction perpendicular to the first end surface and in a direction perpendicular to the mounting surface is formed in the first external electrode, and a second region overlapping the second external electrode in a direction perpendicular to the second end surface and in a direction perpendicular to the mounting surface is formed in the second external electrode, In a second direction perpendicular to the first end face, a via pad provided on a portion of the winding portion included in the coil along the inner circumferential track is provided at a position at least partially overlapping with the first external electrode and the second external electrode, and is provided outside the first region and the second region.

4. The inductor according to any one of claims 1 to 3, characterized in that: The component body includes: a plurality of insulator layers stacked along the first direction, The coil conductor layer is formed in a spiral shape on one main surface of the insulating layer, and the plurality of via-hole conductor layers are formed to penetrate the insulating layer in a thickness direction.

5. The inductor according to claim 4, characterized in that The insulating layer is a non-magnetic body.

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