Coil component and method of manufacturing the same

Abstract

The present invention relates to a coil component and a manufacturing method thereof. The present invention provides a coil component including: a main body composed of a magnetic body; a linear inductor wiring conductor disposed in the main body; an electrically insulating pedestal having a top surface extending along the inductor wiring conductor in the main body and a pair of side surfaces extending from both outer edges of the top surface in directions crossing the top surface; and a conductive seed layer provided at least in an entire region of a region sandwiched by the top surface of the pedestal and the inductor wiring conductor, wherein a width direction dimension of a surface of the inductor wiring conductor in contact with the seed layer is set as a first width direction dimension, and a width direction dimension of the seed layer is set as a second width direction dimension, and the second width direction dimension is wider than the first width direction dimension.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a coil component and a manufacturing method thereof, and particularly to a coil component in which a linear inductor wiring conductor is built in a main body made of a magnetic body and a manufacturing method thereof. BACKGROUND

[0002] In Patent Literature 1, a coil component is described, which includes an insulating substrate, a build-up layer provided on the insulating substrate, a seed layer formed on the build-up layer by non-electrolytic copper plating or the like, an inductor wiring conductor formed on the seed layer by electrolytic copper plating or the like, and an insulating resin coating film covering the inductor wiring conductor.

[0003] Patent Literature 1: Japanese Patent Application Publication No. 2014-32978

[0004] In the above-described coil component, the seed layer is used to supply electric charges when the inductor wiring conductor is formed by plating, and thus is not particularly needed after the inductor wiring conductor is formed. In addition, the seed layer is made of an electrically conductive material, and thus can cause an unwanted electric short circuit. Therefore, after the inductor wiring conductor is formed, the unnecessary part of the seed layer, i.e., the part of the seed layer that is exposed from the inductor wiring conductor, is removed.

[0005] In order to remove the unnecessary part of the seed layer, wet etching is typically applied. However, wet etching not only affects the seed layer, but also affects the inductor wiring conductor. Therefore, the inductor wiring conductor becomes thin, which results in an increase in the resistance value of the inductor wiring conductor, or a decrease in the adhesion force of the inductor wiring conductor to the member that constitutes the base thereof. This problem is more pronounced when, for example, the inductor wiring conductor is made of copper, and the seed layer is made of copper, i.e., when the inductor wiring conductor and the seed layer are made of materials having the same main component as each other. SUMMARY

[0006] Therefore, in the present disclosure, a configuration of a coil component is provided, which can prevent the inductor wiring conductor from becoming thin, which results in an increase in the resistance value of the inductor wiring conductor, or a decrease in the adhesion force of the inductor wiring conductor to the member that constitutes the base thereof, even after the unnecessary part of the seed layer is removed.

[0007] In addition, in the present disclosure, a manufacturing method of a coil component is provided, which does not require a wet etching process in order to remove the unnecessary part of the seed layer.

[0008] The coil component according to one embodiment of the present disclosure includes a main body composed of a magnetic material; a linear inductor wiring conductor disposed in the main body; a pedestal of an electrically insulating material having a top surface extending along the inductor wiring conductor in the main body and a pair of side surfaces extending from both outer edges of the top surface in directions crossing the top surface; and a seed layer of an electrically conductive material disposed at least in an entire region of a region sandwiched by the top surface of the pedestal and the inductor wiring conductor.

[0009] In the coil component, when a width direction dimension of a surface of the inductor wiring conductor contacting the seed layer is set to a first width direction dimension and a width direction dimension of the seed layer is set to a second width direction dimension, the second width direction dimension is wider than the first width direction dimension.

[0010] The manufacturing method of the coil component according to another embodiment of the present disclosure includes the steps of: preparing a support substrate having first and second main surfaces facing each other; providing a pedestal of an electrically insulating material on the first main surface of the support substrate, the pedestal having a top surface extending along a linear inductor wiring conductor to be formed and a pair of side surfaces extending from both outer edges of the top surface in directions crossing the top surface; forming a seed layer of an electrically conductive material so as to cover the pedestal and the first main surface of the support substrate exposed from the pedestal; providing a first resist on the seed layer, the first resist having an opening exposing the seed layer on a width direction central portion of the top surface of the pedestal; forming the inductor wiring conductor on the seed layer by electroplating through the opening of the first resist; removing the first resist; forming a first magnetic layer on the first main surface side of the support substrate so that the inductor wiring conductor is positioned inside; removing the support substrate and a portion of the seed layer other than a portion covering the pedestal from the second main surface side of the support substrate; and forming a second magnetic layer so as to contact the pedestal and the first magnetic layer.

[0011] According to the coil component, the seed layer serving as a base of the inductor wiring conductor is provided to the pedestal, and a width direction dimension of the seed layer is wider than a width direction dimension of a surface of the inductor wiring conductor contacting the seed layer. Therefore, the inductor wiring conductor can be distanced from an unnecessary portion of the seed layer to be removed. Thus, even when wet etching is applied in the removal of the unnecessary portion of the seed layer, the inductor wiring conductor can be less affected by the wet etching. Therefore, a problem that the inductor wiring conductor is thinned, as a result, a resistance value of the inductor wiring conductor is increased, or a close contact force of the inductor wiring conductor with a member constituting the base thereof is reduced, can be less likely to occur.

[0012] In addition, according to the coil component, since the seed layer is provided to the pedestal, by applying a prescribed manufacturing method, an unnecessary portion of the seed layer can be removed without performing a wet etching process.

[0013] According to the manufacturing method of the coil component described above, in order to remove the unnecessary portion of the seed layer, that is, the portion of the seed layer other than the portion covering the pedestal, the process of cutting from the second main surface side of the support substrate is adopted, so that it is not necessary to perform the wet etching process. Therefore, it is possible to avoid the problem that the inductor wiring conductor becomes thin, as a result of which the resistance value of the inductor wiring conductor increases, or the problem that the adhesion of the inductor wiring conductor to the member constituting the base thereof decreases. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a perspective view showing the appearance of the coil component.

[0015] Figure 2 is an enlarged view showing Figure 1 a part of the coil component shown in (A) is a cross section along the line A-A of Figure 1 (B) is a cross section along the line B-B of Figure 1 .

[0016] Figure 3 is a cross-sectional view for explaining Figure 1 the manufacturing method of the coil component shown in (A) shows a part of the support substrate prepared.

[0017] Figure 4 is a cross-sectional view showing the process following Figure 3 the process shown in (A) shows a state in which a pedestal is provided on the first main surface of the support substrate in a portion corresponding to the portion shown in (A). Figure 2

[0018] is a cross-sectional view showing the process following Figure 5 the process shown in (B) shows a state in which a conductive seed layer is formed on the first main surface of the support substrate in a portion corresponding to the portion shown in (B) so as to cover the pedestal and the first main surface of the support substrate exposed from the pedestal. Figure 4 Figure 2 is a cross-sectional view showing the process following

[0019] the process shown in (C) shows a state in which a first resist having an opening exposing the seed layer on the central portion in the width direction of the top surface of the pedestal is provided on the seed layer in a portion corresponding to the portion shown in (C). Figure 6 Figure 5 Figure 2 is a cross-sectional view showing the process following the process shown in (D) shows a state in which an inductor wiring conductor is formed on the seed layer via the opening of the first resist in a portion corresponding to the portion shown in (D).

[0020] Figure 7 Figure 6 is a cross-sectional view showing the process following Figure 2 the process shown in (E) shows a state in which the first resist is removed in a portion corresponding to the portion shown in (E). ​​

[0021] Figure 8 is a sectional view of the process subsequent to the process shown in Figure 7 Figure 2 (A) is a state where the first resist is removed from a portion corresponding to the portion shown in

[0022] Figure 9 is a sectional view of the process subsequent to the process shown in Figure 8 Figure 2 (A) is a state where the second resist is provided on the seed layer in a portion corresponding to the portion shown in Figure 2 (B) is a state where the second resist is provided on the seed layer in a portion corresponding to the portion shown in (B), the second resist having an opening corresponding to a pattern of the lead conductor electrically connected to the end portion of the inductor wiring conductor.

[0023] Figure 10 is a sectional view of the process subsequent to the process shown in Figure 9 Figure 2 (A) is a state where the second resist is maintained in a state shown in (A) in a portion corresponding to the portion shown in Figure 9 (A) is a state where the second resist is maintained in a state shown in (A) in a portion corresponding to the portion shown in Figure 2 (B) is a state where the lead conductor is formed on the end portion of the inductor wiring conductor by electroplating via the opening of the second resist in a portion corresponding to the portion shown in (B).

[0024] Figure 11 is a sectional view of the process subsequent to the process shown in Figure 10 Figure 2 (A) is a state where the second resist is removed from a portion corresponding to the portion shown in (A), (B) is a state where the second resist is removed from a portion corresponding to the portion shown in Figure 2 (A) is a state where the second resist is removed from a portion corresponding to the portion shown in (A), (B) is a state where the second resist is removed from a portion corresponding to the portion shown in

[0025] Figure 12 is a sectional view of the process subsequent to the process shown in Figure 11 Figure 2 (A) is a state where the first magnetic layer is provided on the first main surface side of the support substrate so that the inductor wiring conductor is located inside in a portion corresponding to the portion shown in (A), (B) is a state where the first magnetic layer is provided so that the lead conductor is also built-in together with the inductor wiring conductor in a portion corresponding to the portion shown in Figure 2 (A) is a state where the first magnetic layer is provided on the first main surface side of the support substrate so that the inductor wiring conductor is located inside in a portion corresponding to the portion shown in (A), (B) is a state where the first magnetic layer is provided so that the lead conductor is also built-in together with the inductor wiring conductor in a portion corresponding to the portion shown in

[0026] Figure 13 is a sectional view of the process subsequent to the process shown in Figure 12 Figure 2 ​​​​​​(A) is a cross-sectional view of a portion corresponding to the portion shown in (B) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 2 (B) is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor.

[0027] Figure 14 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 13 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 2 (A) is a cross-sectional view of a portion corresponding to the portion shown in (B) in a state where the first magnetic layer is provided with a solder resist. Figure 2 (B) is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is provided with a solder resist.

[0028] Figure 15 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 14 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 2 (A) is a cross-sectional view of a portion corresponding to the portion shown in (B) in a state where the support substrate is removed, and further, a portion other than the portion where the overhanging pedestal of the seed layer is removed from the second main surface side of the support substrate. Figure 2 (B) is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the support substrate is removed, and further, a portion other than the portion where the overhanging pedestal of the seed layer is removed from the second main surface side of the support substrate.

[0029] Figure 16 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 15 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 2 (A) is a cross-sectional view of a portion corresponding to the portion shown in (B) in a state where the second magnetic layer is provided in contact with the pedestal and the first magnetic layer. Figure 2 (B) is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the second magnetic layer is provided in contact with the pedestal and the first magnetic layer.

[0030] Figure 17 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 15 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 2 (B) is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the base layer of the external terminal electrode electrically connected to the lead conductor is formed.

[0031] Figure 18 is an enlarged cross-sectional view showing a portion of the coil member, (A) is a cross-section corresponding to the cross-section along line A-A of Figure 1 (B) is a cross-section corresponding to the cross-section along line B-B of Figure 1 .

[0032] Figure 19 is a cross-sectional view of a portion corresponding to the portion shown in (A) in a state where the first magnetic layer is cut away to expose the end surface of the lead conductor. Figure 18A cross-sectional view of the manufacturing method of the coil component 1a shown, (A) indicates a state in which a resist for a preparation stage of a process of removing an unnecessary portion of the seed layer is provided in a portion corresponding to the portion shown in (B), and (B) indicates a state in which the resist is removed after the unnecessary portion of the seed layer is removed. Figure 18 (A) shown, (B) indicates a state in which a resist for a preparation stage of a process of removing an unnecessary portion of the seed layer is provided in a portion corresponding to the portion shown in (A). Figure 18 (B) shown, (B) indicates a state in which a resist for a preparation stage of a process of removing an unnecessary portion of the seed layer is provided in a portion corresponding to the portion shown in (A).

[0033] Figure 20 is a cross-sectional view of the process shown next. Figure 19 is a cross-sectional view of the process shown next. Figure 18 (A) shown, (B) indicates a state in which a resist for a preparation stage of a process of removing an unnecessary portion of the seed layer is provided in a portion corresponding to the portion shown in (A). Figure 18 (B) shown, (B) indicates a state in which a resist for a preparation stage of a process of removing an unnecessary portion of the seed layer is provided in a portion corresponding to the portion shown in (A).

[0034] Figure 21 is a cross-sectional view showing a formation state of the seed layer provided in the coil component in an enlarged manner.

[0035] Figure 22 is a cross-sectional view showing a formation state of the seed layer provided in the coil component in an enlarged manner.

[0036] Figure 23 is a cross-sectional view showing a formation state of the seed layer provided in the coil component in an enlarged manner.

[0037] Figure 24 is a cross-sectional view showing a portion of the adhesion layer formed between the pedestal and the seed layer in the coil component in an enlarged manner.

[0038] BRIEF DESCRIPTION OF DRAWINGS

[0039] 1, 1a... coil component; 2... main body; 9 to 11... inductor wiring conductor; 13 to 18... lead conductor; 19 to 24... external terminal electrode; 25 to 27... pedestal; 28... top surface; 29, 30... side surface; 31... seed layer; 33... support substrate; 34... first main surface; 35... second main surface; 38... first resist; 39, 41, 44... opening; 40... second resist; 42... first magnetic layer; 45... second magnetic layer; 53... adhesion layer. DETAILED DESCRIPTION

[0040] [First Embodiment]

[0041] Referring to Figure 1 and Figure 2 , the configuration of the coil component 1 of the first embodiment of the present disclosure will be described.

[0042] The coil component 1 has a main body 2 made of a magnetic material. The magnetic material constituting the main body 2 is made of, for example, an organic material containing metal magnetic powder. The metal magnetic powder is, for example, powder having an average particle diameter of 5 μm or less and made of an alloy containing Fe such as an Fe-Si-based alloy. Further, the metal magnetic powder can be crystalline or amorphous. Further, an oxide magnetic powder such as ferrite can be used instead of the metal magnetic powder. As the organic material, for example, an epoxy resin, a mixture of an epoxy resin and an acrylic resin, or a mixture of an epoxy resin, an acrylic resin, and another resin is used.

[0043] The main body 2 is plate-shaped or cuboid-shaped, has an upper surface 3 and a lower surface 4, and has four end surfaces 5, 6, 7, and 8 connecting between the upper surface 3 and the lower surface 4. The "upper surface" and the "lower surface" are Figure 1 the upper and lower surfaces of the main body 2, and are not indicative of the upper and lower surfaces of the coil component 1 in the actual use state. Further, a solder resist 43 described later is provided on the upper surface 3 of the main body 2. Three inductor wiring conductors 9, 10, and 11 are arranged in the main body 2. The inductor wiring conductors 9, 10, and 11 extend in a direction connecting between the end surfaces 5 and 6 facing each other. The inductor wiring conductors 9 and 10 are straight, and the inductor wiring conductor 11 is meandering. Further, the inductor wiring conductor 9 is thicker than the inductor wiring conductors 10 and 11.

[0044] A lead conductor 13 and a lead conductor 14 are provided at one end portion and the other end portion of the inductor wiring conductor 9, respectively. A lead conductor 15 and a lead conductor 16 are provided at one end portion and the other end portion of the inductor wiring conductor 10, respectively. A lead conductor 17 and a lead conductor 18 are provided at one end portion and the other end portion of the inductor wiring conductor 11, respectively. The lead conductors 13 to 18 are connected to the inductor wiring conductors 9 to 11, respectively. Figure 2 As is apparent from the state of the lead conductor 14 illustrated in (B), each of the lead conductors 13 to 18 is arranged so as to overlap with the corresponding end portion of each of the inductor wiring conductors 9 to 11. Further, each of the inductor wiring conductors 9 to 11 is wider at each end connected to each of the lead conductors 13 to 18 than at other portions.

[0045] The inductor wiring conductors 9 to 11 and the lead conductors 13 to 18 are made of, for example, Au, Pt, Pd, Ag, Cu, Al, Co, Cr, Zn, Ni, Ti, W, Fe, Sn, or In, or a compound containing any of them.

[0046] Six external terminal electrodes 19 to 24 are provided to the outer surface of the main body 2, more specifically, the upper surface 3. One end portion of the inductor wiring conductor 9 is electrically connected to the external terminal electrode 19 via the lead conductor 13, and the other end portion is electrically connected to the external terminal electrode 20 via the lead conductor 14. One end portion of the inductor wiring conductor 10 is electrically connected to the external terminal electrode 21 via the lead conductor 15, and the other end portion is electrically connected to the external terminal electrode 22 via the lead conductor 16. One end portion of the inductor wiring conductor 11 is electrically connected to the external terminal electrode 23 via the lead conductor 17, and the other end portion is electrically connected to the external terminal electrode 24 via the lead conductor 18.

[0047] Also provided within the main body 2 are seats 25, 26, and 27 of electrically insulating properties. The seats 25 to 27 are composed of, for example, epoxy resin, acrylic resin, phenol resin, or polyimide, or a mixture thereof.

[0048] In Figure 2 (A) and Figure 2 (B), the seat 25 is clearly shown. The seat 25 has a top surface 28 extending along the inductor wiring conductor 9, and a pair of side surfaces 29 and 30 extending from both outer edges of the top surface 28 in directions crossing the top surface 28. Although detailed illustration is omitted, the seat 26 has a top surface extending along the inductor wiring conductor 10, and a pair of side surfaces extending from both outer edges of the top surface in directions crossing the top surface, and the seat 27 has a top surface extending along the inductor wiring conductor 11, and a pair of side surfaces extending from both outer edges of the top surface in directions crossing the top surface. Furthermore, as shown in Figure 2 (A) and Figure 2 (B), a slope can also be imparted to the side surfaces 29 and 30 of the seat 25.

[0049] Furthermore, when the slope is expressed by the internal angle of the top surface 28 and the side surface 29, or the internal angle of the top surface 28 and the side surface 30, the slope is preferably 120° or more and 160° or less. The slope is 120° or more, whereby the width of the seed layer 31 can be made wider than the width of the inductor wiring conductor 9 more reliably. In addition, the slope is 160° or less, whereby the seat 25 does not expand excessively, and the volume of the main body 2 as a magnetic body can be ensured, whereby the decrease in the efficiency of attaining the inductance value can be suppressed.

[0050] A conductive seed layer 31 is provided at least over the entire area of ​​the area sandwiched between the top surface 28 of the pedestal 25 and the inductor wiring conductor 9. In the present embodiment, the seed layer 31 is provided over the entire area of ​​the top surface 28 and the side surfaces 29 and 30 of the pedestal 25. The seed layer 31 is preferably composed of a material having the same main component as the inductor wiring conductors 9 to 11, for example, Au, Pt, Pd, Ag, Cu, Al, Co, Cr, Zn, Ni, Ti, W, Fe, Sn or In, or a compound thereof. In addition, depending on the formation method, the seed layer 31 may also have a component structure other than the main component that is different from that of the inductor wiring conductors 9 to 11. In addition, the thickness of the seed layer 31 is not particularly limited as long as it can supply charge and fully function in electroplating, but is preferably 2 μm or less, for example.

[0051] In this embodiment, Figure 2 The width dimension W21 of the seed layer 31 is larger than the width dimension W11 of the surface of the inductor wiring conductor 9 in contact with the seed layer 31 shown in (A). Figure 2 In FIG. 1B , the width dimension W22 of the seed layer 31 is greater than the width dimension W12 of the surface of the end portion of the inductor wiring conductor 9 in contact with the seed layer 31. In other words, the seed layer 31 is provided so as to extend outside the inductor wiring conductor 9.

[0052] In addition, regarding the widthwise dimensions W11 and W12, these are defined as "the widthwise dimensions of the surface of the inductor wiring conductor 9 in contact with the seed layer 31" because the widthwise dimensions of the inductor wiring conductor 9 other than the surface in contact with the seed layer 31 are not particularly limited. For example, Figure 2 As in the case where the cross-sectional shape of the inductor wiring conductor 9 is an inverted trapezoid, the width dimension of the surface other than the surface in contact with the seed layer 31 may be the same as or wider than the width dimension W21 or W22 of the seed layer 31. Furthermore, the width direction of the inductor wiring conductor 9 and seed layer 31 refers to the direction parallel to the top surface 28 of the pedestal 25 in a cross section (transverse section) perpendicular to the extending direction of the inductor wiring conductor 9 and seed layer 31.

[0053] The seed layer 31 is used to supply charge when forming the inductor wiring conductor 9 by electroplating, and therefore is no longer necessary after the inductor wiring conductor 9 has been formed. Furthermore, the seed layer 31 is made of a conductive material, which can cause undesirable electrical short circuits. Therefore, after forming the inductor wiring conductor 9, the unnecessary portion of the seed layer 31 is removed. Wet etching is typically used to remove the unnecessary portion of the seed layer 31.

[0054] It should be understood as Figure 2indicates a state after the unnecessary portion of the seed layer 31 is removed. Therefore, before the unnecessary portion is removed, the seed layer 31 is, for example, patterned as described later Figure 5 to Figure 14 indicated to extend wider to the side of the inductor wiring conductor 9. As described above, if the width direction dimensions W21 and W22 are made wider than the width direction dimensions W11 and W12, respectively, the inductor wiring conductor 9 can be made to be distanced from the unnecessary portion of the seed layer 31 to be removed. Therefore, even if wet etching is applied in the removal of the unnecessary portion of the seed layer 31, for example, the inductor wiring conductor 9 can be made not to be easily affected by the wet etching.

[0055] The above has been described in association with Figure 2 the inductor wiring conductor 9, the pedestal 25, and the seed layer 31, but the other inductor wiring conductors 10 and 11, the other pedestals 26 and 27, and the seed layers provided thereon also have substantially the same structure.

[0056] Next, the preferred manufacturing method of the coil component 1 will be described with reference to Figure 3 to Figure 17 Fig. 10. Figure 3 to Figure 17 The manufacturing method associated with the portion provided with the inductor wiring conductor 9 is illustrated. The same processes as those illustrated in Figure 3 to Figure 17 indicated in Fig. 10 are performed for the portion provided with the other inductor wiring conductors 10 and 11.

[0057] First, as indicated in Figure 3 Fig. 11, a support substrate 33 is prepared. The support substrate 33 has a first main surface 34 and a second main surface 35 which oppose each other. The support substrate 33 is composed of a base portion 36 and a coating portion 37, the base portion 36 is located on the second main surface 35 side and is composed of a material having relatively high strength against flexure such as ferrite, and the coating portion 37 is located on the first main surface 34 side and covers one main surface of the base portion 36 and is composed of a resin such as polyimide. The coating portion 37 is formed by, for example, applying the resin on the base portion 36 by spin coating and then curing. Although not illustrated, an alignment mark is formed on the first main surface 34 given by the coating portion 37 as necessary.

[0058] Next, as indicated in Figure 4 Fig. 12, the pedestal 25 is formed on the first main surface 34 given by the coating portion 37 of the support substrate 33. In order to form the pedestal 25, the desired resin is spin coated on the first main surface 34 of the support substrate 33, and then the processes of exposure, development, and curing are performed to patternize. Figure 4 A portion corresponding to the portion indicated in Figure 2 (A) is illustrated, but the pedestal 25 extends to the portion indicated in Figure 2As described above, the base 25 has a top surface 28 extending along the linear inductor wiring conductor 9 to be formed, and a pair of side surfaces 29 and 30 extending from both outer edges of the top surface 28 in a direction intersecting the top surface 28.

[0059] Next, if Figure 5 As shown, a conductive seed layer 31 is formed. The seed layer 31 is formed by, for example, applying Cu electroless plating, sputtering, etc., so as to cover the pedestal 25 and the first main surface 34 of the support substrate 33 exposed from the pedestal 25 .

[0060] Next, if Figure 6 As shown, a first resist 38 is provided on the seed layer 31. The first resist 38 has an opening 39 that exposes the seed layer 31 in the widthwise center portion of the top surface 28 of the pedestal 25. The first resist 38 is formed, for example, of a dry film resist. More specifically, while the protective film is being peeled off, the dry film resist is laminated onto the seed layer 31 and patterned through exposure, development, and curing steps to form the first resist 38 having the opening 39.

[0061] Next, if Figure 7 As shown, the inductor wiring conductor 9 is formed by electroplating of a conductive metal such as Cu. The conductive metal to become the inductor wiring conductor 9 grows by plating on the seed layer 31 supplied with charges through the openings 39 of the first resist 38, thereby forming the inductor wiring conductor 9.

[0062] Next, if Figure 8 As shown, the first resist 38 is stripped and removed.

[0063] Next, if Figure 9 As shown, a second resist 40 is provided on the seed layer 31. The second resist 40 is formed on the seed layer 31. Figure 9 (B) shown with Figure 2 The portion corresponding to the portion shown in (B) has an opening 41 having a pattern corresponding to the pattern of the lead conductor 14 electrically connected to the end of the inductor wiring conductor 9. The second resist 40 is formed, for example, of a dry film resist. More specifically, as in the case of the first resist 38, while peeling off the protective film, the dry film resist is laminated on the seed layer 31, and patterned through exposure, development, and curing steps, thereby forming the second resist 40 having the opening 41. Figure 9 (A) shown with Figure 2 In the portion corresponding to the portion shown in (A), the lead conductor 14 is not formed, and therefore the opening 41 is not formed.

[0064] Next, if Figure 10 As shown, electroplating of a conductive metal such as Cu is performed.Figure 10 (B) shown in the portion equivalent to Figure 2 (B) shown in the portion equivalent to Figure 10 (A) shown in the portion equivalent to Figure 2 (A) shown in the portion equivalent to Figure 9 (A) shown in the state.

[0065] Next, as shown in Figure 11 (B) shown in the portion equivalent to (B) shown in the portion equivalent to

[0066] Next, as shown in Figure 12 (B) shown in the portion equivalent to Figure 12 (B) shown in the portion equivalent to Figure 2 (B) shown in the portion equivalent to Figure 12 (A) shown in the portion equivalent to Figure 2 (A) shown in the portion equivalent to Figure 12 (A) shown in the state, and then cured to form.

[0067] Next, as shown in Figure 13 (B) shown in the portion equivalent to Figure 13 (B) shown in the portion equivalent to Figure 2 (B) shown in the portion equivalent to Figure 13 (A) shown in the portion equivalent to Figure 2 (A) shown in the portion equivalent to

[0068] Next, as shown in Figure 14 (B) shown in the portion equivalent to Figure 14 (B) shown in the portion equivalent to Figure 2 (B) shown in the portion equivalent to Figure 14 (A) shown in the portion equivalent to Figure 2(A) the portion equivalent to the portion shown in (B) is a portion in which the solder resist 43 is not provided with the opening.

[0069] Next, as shown in Figure 15 , in order to expose the pedestal 25 on the second main surface 35 side of the support substrate 33, the support substrate 33 and the seed layer 31 are removed from the second main surface 35 side of the support substrate 33 (refer to Figure 14 ) except for the portions thereof covering the pedestal 25. In this way, the unnecessary portions of the seed layer 31 can be removed without implementing a wet etching process.

[0070] Next, as shown in Figure 16 , the second magnetic layer 45 is provided in contact with the pedestal 25 and the first magnetic layer 42. The second magnetic layer 45 is formed, for example, by punching a sheet material composed of an organic material containing a metal magnetic powder, in the state shown in Figure 16 , and then being cured. The main body 2 is composed of the second magnetic layer 45 and the above-described first magnetic layer 42.

[0071] Further, the above-described Figure 14 process of providing the solder resist 43 on the surface of the first magnetic layer 42 can be implemented after the process of removing the support substrate 33 shown in Figure 15 , or after the process of providing the second magnetic layer 45 shown in Figure 16 .

[0072] Next, as shown in Figure 17 , a base layer 46 of an external terminal electrode 20 electrically connected to the lead conductor 14 is formed in a portion equivalent to the portion shown in Figure 2 (B) in the opening 44 of the solder resist 43. The base layer 46 is provided, for example, by a Cu non-electrolytic plating layer, and further, a surface layer 47 composed of a Ni plating layer and an Au plating layer is formed on the base layer 46, as shown in Figure 2 (B).

[0073] In this way, the coil component 1 is manufactured, but in the case where the above-described processes are implemented in a mother state in order to simultaneously manufacture a plurality of coil components 1, thereafter, a process of cutting the assembly of the coil components 1 in the mother state by, for example, a cutting machine is implemented.

[0074] [Second Embodiment]

[0075] The second embodiment of the present disclosure will be described with reference to Figure 18 to Figure 20 . In Figure 18 to Figure 20 , elements equivalent to the elements shown in Figure 2 to Figure 17 are labeled with the same reference numerals, and overlapping descriptions will be omitted.

[0076] Figure 18 is equivalent to Figure 2Corresponding Figure. In the coil component 1 according to the first embodiment, the seed layer 31 is provided over the entire top surface 28 and side surfaces 29 and 30 of the pedestal 25 , but in the coil component 1 a according to the second embodiment, the seed layer 31 is provided only on the top surface 28 of the pedestal 25 .

[0077] To manufacture the coil component 1a according to the second embodiment, first, the manufacturing method according to the first embodiment is carried out in the same manner as above. Figure 11 The process shown.

[0078] then Figure 11 The process shown, such as Figure 19 As shown, a resist 51 is provided on the seed layer 31. The resist 51 is formed of, for example, a dry film resist. More specifically, while peeling off the protective film, the dry film resist is laminated on the seed layer 31 and patterned through exposure, development, and curing processes. Figure 19 (A) shown with Figure 2 The portion shown in (A) corresponds to the portion where the resist 51 is formed to cover the inductor wiring conductor 9 and the portion of the seed layer 31 located on the top surface 28 of the pedestal 25. Figure 19 (B) shown with Figure 2 The portion corresponding to the portion shown in (B) is formed with resist 51 that covers the inductor wiring conductor 9 and the lead conductor 14 and also covers the portion of the seed layer 31 that is located on the top surface 28 of the pedestal 25 .

[0079] Next, in Figure 19 In the state shown, a wet etching process is performed on the seed layer 31. Thus, the seed layer 31 is removed from the portion exposed from the resist 51. Figure 20 The state in which the resist 51 is removed after the unnecessary portion of the seed layer 31 is removed is shown.

[0080] Afterwards, the implementation of the above Figure 12 The process of setting the first magnetic layer 42 shown in FIG. Figure 13 The first magnetic layer 42 is cut to expose the end surface of the lead conductor 14. Figure 14 The process of providing the solder resist 43 on the first magnetic layer 42 is shown. Figure 15 The step of removing the support substrate 33 shown, Figure 16 The process of providing the second magnetic layer 45 in contact with the pedestal 25 and the first magnetic layer 42, and Figure 17 Each of the steps of forming the base layer 46 of the external terminal electrode 20 shown in FIG. 1 is substantially the same as the steps of forming the surface layer 47 of the external terminal electrode 20. Figure 18 The coil component 1a is shown.

[0081] According to the second embodiment, the inductor wiring conductor 9 is protected at the time of wet etching, and thus the inductor wiring conductor 9 does not become thin, as compared with the case where wet etching is applied in the state shown in FIG. 6. Figure 11 Figure 11 According to the second embodiment, the inductor wiring conductor 9 is protected at the time of wet etching, and thus the inductor wiring conductor 9 does not become thin, as compared with the case where wet etching is applied in the state shown in FIG. 6.

[0082] [Third to Fifth Embodiments]

[0083] The third to fifth embodiments are described in association with the pedestal 25 shown in FIG. 7. Although description is omitted, the same applies to the other pedestals 26 and 27. Figure 21 to Figure 23 In the first embodiment, wet etching is not applied at all, but in the third to fifth embodiments, wet etching is applied for a short time in the state shown in FIG. 7. Thus, the seed layer 31 is subjected to incomplete etching at the portion exposed from the inductor wiring conductor 9.

[0084] Figure 11 More specifically, in the third embodiment shown in FIG. 7, the seed layer 31 is incompletely etched at a portion of the top surface 28 and each of the side surfaces 29 and 30 of the pedestal 25.

[0085] More specifically, in the third embodiment shown in FIG. 7, the seed layer 31 is incompletely etched at a portion of the top surface 28 and each of the side surfaces 29 and 30 of the pedestal 25. Figure 21 In the fourth embodiment shown in FIG. 8, the seed layer 31 is incompletely etched at a portion of the top surface 28 of the pedestal 25.

[0086] Figure 22 In the fifth embodiment shown in FIG. 9, the seed layer 31 is incompletely etched at each of a portion of the side surfaces 29 and 30 of the pedestal 25.

[0087] In the fifth embodiment shown in FIG. 9, the seed layer 31 is incompletely etched at each of a portion of the side surfaces 29 and 30 of the pedestal 25. Figure 23 In the third to fifth embodiments described above, the incomplete etching results in formation of an interrupted portion on at least one of the top surface 28 and the side surfaces 29 and 30 of the pedestal 25 in the seed layer 31.

[0088] According to these third to fifth embodiments, as compared with the second embodiment, the area of the seed layer 31 in contact with the pedestal 25 increases, or the distribution area of the portion of the seed layer 31 in contact with the pedestal 25 widens, and thus the adhesion of the seed layer 31 to the pedestal 25 can be improved. In addition, according to the third to fifth embodiments, although the seed layer 31 is incompletely etched in the state shown in FIG. 7, the seed layer 31 is not completely removed, and thus the seed layer 31 is not completely removed even if the seed layer 31 is removed by etching in the state shown in FIG. 6.

[0089] Figure 21 to Figure 23 ​​​​Although not illustrated, a rough surface is formed at the boundary of the pedestal 25 and the first magnetic layer 42, and thus an effect of improving the adhesion of the first magnetic layer 42 to the pedestal 25 can also be expected.

[0090] [Sixth Embodiment]

[0091] Reference Figure 24 The sixth embodiment will be described in association with the pedestal 25. Although the description is omitted, the same applies to the other pedestals 26 and 27.

[0092] The sixth embodiment is characterized in that an adhesion layer 53 for improving the adhesion of the seed layer 31 to the pedestal 25 is further provided between the seed layer 31 and the pedestal 25. The material of the adhesion layer 53 can be appropriately selected as a material suitable for the purpose of improving the adhesion, as long as the material does not have an influence on the formation of the inductor wiring conductor 9. As one example, in the case where Ti is not used as the material of the seed layer 31, the adhesion layer 53 is preferably composed of a Ti layer.

[0093] The sixth embodiment can also be applied in combination with any one of the above-described first to fifth embodiments.

[0094] The above describes the present disclosure in association with the illustrated several embodiments, but various modifications can be made within the scope of the present disclosure.

[0095] For example, the form, number, and the like of the inductor wiring conductor of the coil member can be arbitrarily changed according to the design. The inductor wiring conductor may, for example, also extend in a spiral shape.

[0096] In addition, regarding the configuration of the coil member according to the present disclosure, the method of forming the inductor wiring conductor is not limited, and in addition to the above-described electroplating method, a non-electrolytic plating method, a sputtering method, an evaporation method, a printing method, and the like can also be applied.

[0097] In addition, each of the embodiments described in this specification is merely an example, and partial replacement or combination of structures can be made between different embodiments.

Claims

1. A coil component, wherein: have: The main body is composed of a magnetic body; a linear inductor wiring conductor disposed within the main body; an electrically insulating base having a top surface extending along the inductor wiring conductor within the main body, and a pair of side surfaces extending from both outer edges of the top surface in a direction intersecting the top surface; as well as A conductive seed layer is provided at least over the entire region sandwiched between the top surface of the pedestal and the inductor wiring conductor. When the width dimension of the surface of the inductor wiring conductor in contact with the seed layer is defined as a first width dimension and the width dimension of the seed layer is defined as a second width dimension, the second width dimension is wider than the first width dimension. The coil component further includes an adhesion layer for improving adhesion between the seed layer and the base.

2. The coil component according to claim 1, wherein The coil component further comprises: External terminal electrodes are provided to be exposed on the outer surface of the main body; and The lead conductor is arranged to overlap with an end portion of the inductor wiring conductor and electrically connects the end portion of the inductor wiring conductor to the external terminal electrode.

3. The coil component according to claim 1 or 2, wherein The seed layer is disposed on the top surface and the side surface of the base. The coil component according to claim 3 , wherein: The seed layer is provided on the entire area of ​​each of the top surface and the side surface of the pedestal.

5. The coil component according to claim 3, wherein The seed layer has a discontinuous portion on a portion of at least one of the top surface and the side surface of the pedestal.

6. The coil component according to claim 1 or 2, wherein The seed layer is disposed on the top surface of the pedestal but not on the side surface of the pedestal.

7. The coil component according to claim 1 or 2, wherein The inductor wiring conductor and the seed layer are made of a material having the same main component.

8. The coil component according to claim 1 or 2, wherein The base is made of resin.

9. A method for manufacturing a coil component, wherein: With the following processes: a step of preparing a supporting substrate having a first main surface and a second main surface facing each other; a step of providing an electrically insulating pedestal on the first main surface of the support substrate, the pedestal having a top surface extending along a linear inductor wiring conductor to be formed, and a pair of side surfaces extending from both outer edges of the top surface in a direction intersecting the top surface; forming a conductive seed layer so as to cover the pedestal and the first main surface of the support substrate exposed from the pedestal via an adhesive layer for improving the adhesiveness between the seed layer and the pedestal; a step of providing a first resist on the seed layer, the first resist having an opening exposing the seed layer at a center portion in a width direction of the top surface of the pedestal; forming an inductor wiring conductor on the seed layer through the opening of the first resist by electroplating; a step of removing the first resist; a step of providing a first magnetic layer on the first main surface side of the support substrate so that the inductor wiring conductor is located inside; a step of removing the support substrate and a portion of the seed layer except for a portion covering the pedestal from the second main surface side of the support substrate; as well as a step of providing a second magnetic layer so as to be in contact with the pedestal and the first magnetic layer.

10. The method for manufacturing a coil component according to claim 9, wherein: After the step of removing the first resist, the following step is further included: a step of providing a second resist on the seed layer, the second resist having openings having a pattern corresponding to a pattern of a lead conductor electrically connected to an end portion of the inductor wiring conductor; forming a lead conductor on the end portion of the inductor wiring conductor through the opening of the second resist by electroplating; as well as a step of removing the second resist, The step of forming the first magnetic layer is performed so that the first magnetic layer also includes the lead conductor and the inductor wiring conductor. The method for manufacturing the coil component further comprises the following steps: After forming the first magnetic layer, cutting the first magnetic layer to expose the end surface of the lead conductor; and a step of forming an external terminal electrode electrically connected to the lead conductor.

Images