Coil component

Abstract

To provide a coil component that restrains plating elongation and is advantageous to miniaturization.SOLUTION: A lamination coil component includes an element body 2 containing a magnetic material, a coil embedded in the element body, external electrodes 8a and 8b which are electrically connected to the coil and provided on the bottom surface of the element body, and an insulating layer 7 provided on the bottom surface of the element body. The insulating layer has opening portions 9a and 9b, and the external electrodes 8a and 8b are provided in the opening portions.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] A multilayer coil component having a magnetic body portion containing metal magnetic powder is known. Since the metal magnetic powder contained in the magnetic body portion is conductive particles containing iron or the like, there is a risk of plating growth. Therefore, in order to ensure the surface insulation, it is known to apply an insulating coating having a high insulation resistance to the upper surface and the lower surface (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the multilayer coil component as described in Patent Document 1, since the upper surface and the lower surface are provided with an insulating coating, it is difficult to miniaturize and lower the profile.

[0005] An object of the present disclosure is to provide a coil component in which plating growth is suppressed and which is advantageous for miniaturization and lower profile.

Means for Solving the Problems

[0006] The present disclosure includes the following aspects. [1] A body containing a magnetic material, a coil embedded in the body, an external electrode electrically connected to the coil and provided on the bottom surface of the body, an insulating layer provided on the bottom surface of the body, and a multilayer coil component having The insulating layer has an opening, wherein an external electrode is provided in the opening, Coil component. [2] The external electrode includes a bottom electrode and a plating layer provided on the bottom electrode, and the coil component according to [1] above. [3] The bottom electrode is provided in the element body, and the plating layer is provided in the opening, and the coil component according to [2] above. [4] In a plan view from the bottom surface side of the element body, the area of the opening is equal to or less than the area of the bottom electrode, and the coil component according to any one of [1] to [3] above. [5] The plating layer is provided flush with the insulating layer, and the coil component according to any one of [1] to [4] above. [6] The plating layer is recessed from the bottom surface of the insulating layer, and the coil component according to any one of [1] to [4] above. [7] The plating layer is provided so as to protrude from the insulating layer, and the coil component according to any one of [1] to [4] above. [8] The plating layer is a Cu layer, a Ni - Sn layer, a Ni - Au layer, a Ni - Cu layer, or a Cu - Ni - Au layer, and the coil component according to any one of [1] to [7] above. [9] The insulating layer is a resin material having a higher insulation resistance than the element body, and the coil component according to any one of [1] to [8] above.

[10] The magnetic material contains metal magnetic particles, and the coil component according to any one of [1] to [9] above.

[11] A method for manufacturing a laminated coil component having a magnetic material-containing element body, a coil embedded in the element body, an external electrode electrically connected to the coil and provided on the bottom surface of the element body, and an insulating layer provided on the bottom surface of the element body, including a magnetic paste layer and a conductor paste layer, laminating a conductor paste layer that becomes a bottom electrode on the bottom surface, and firing to produce a laminate block, Forming an insulating layer having an opening that exposes at least a partial region of the bottom electrode on the surface of the fired laminate block where the bottom electrode is exposed; Forming a plating layer on the bottom electrode in the opening; Cutting the laminate block; A method for manufacturing a coil component including the above.

Advantages of the Invention

[0007] According to the present disclosure, by forming an external electrode within the opening of the insulating layer, plating growth is suppressed, and furthermore, a coil component advantageous for miniaturization and low profile can be provided.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0009] The coil component of the present disclosure will be described in detail below with reference to the drawings. However, the coil component of the present disclosure and the shapes and arrangements of the respective components are not limited to the illustrated examples. In each drawing, members having the same function may be denoted by the same reference numeral. For the sake of easy explanation or understanding of the gist, the description is divided into embodiments for convenience, but partial substitution or combination of the configurations shown in different embodiments is possible. In the embodiments described later, the description of matters common to the foregoing may be omitted, and only the different points may be described. In particular, the same operational effects due to the same configuration may not be sequentially mentioned for each embodiment. The sizes and positional relationships of the members shown in each drawing may be exaggerated for clarity of explanation.

[0010] (Embodiment 1) A perspective view of the multilayer coil component 1 of this embodiment is shown in FIG. 1, and a bottom view is shown in FIG. 6. Also, a cross-sectional view taken along line II-II of the multilayer coil component 1 is schematically shown in FIG. 2, a cross-sectional view taken along line III-III is shown in FIG. 3, a cut surface along line IV-IV is shown in FIG. 4, and a cross-sectional view taken along line V-V is shown in FIG. 5.

[0011] As shown in FIGS. 1 to 6, the multilayer coil component 1 of this embodiment has a substantially rectangular parallelepiped shape. In FIG. 1, the lower surface is referred to as the bottom surface, the upper surface is referred to as the upper surface, and the other surfaces are referred to as side surfaces. The multilayer coil component 1 generally includes a base body 2, a coil 3 embedded in the base body 2, external electrodes 8a and 8b, and an insulating layer 7 covering the bottom surface of the base body 2. The insulating layer 7 has openings 9a and 9b. The external electrodes 8a and 8b are respectively present in the openings 9a and 9b. The coil 3 is formed by connecting a plurality of internal electrode layers 3a to 3e by via conductors 3p to 3s. The external electrodes 8a and 8b have bottom electrodes 5a and 5b located inside the base body 2, and plating layers 6a and 6b provided on the bottom electrodes 5a and 5b and located in the openings 9a and 9b. The external electrodes 8a and 8b are electrically connected to both ends of the coil 3 via lead-out portions 4a and 4b, respectively.

[0012] The coil component of the present disclosure preferably has a length (L) of 1.0 mm or more and 6.0 mm or less, a width (W) of 0.2 mm or more and 2.0 mm or less, and a height (T) of 0.2 mm or more and 2.0 mm or less. More preferably, the length is 1.0 mm or more and 2.0 mm or less, the width is 0.5 mm or more and 1.2 mm or less, and the height is 0.5 mm or more and 1.2 mm or less.

[0013] In this embodiment, the base body 2 includes a magnetic layer containing a magnetic material.

[0014] Typically, the magnetic material is metal magnetic particles.

[0015] The metal magnetic material constituting the metal magnetic particles is not particularly limited as long as it has magnetism. For example, it includes iron, cobalt, nickel, gadolinium, or an alloy containing one or more of these. Preferably, the metal magnetic material is iron or an iron alloy. Iron may be iron itself or an iron derivative, such as a complex. Such an iron derivative is not particularly limited, but examples include carbonyl iron, which is a complex of iron and CO, preferably pentacarbonyl iron. In particular, hard-grade carbonyl iron having an onion skin structure (a structure forming concentric spherical layers from the center of the particles), for example, hard-grade carbonyl iron manufactured by BASF, is preferred. The iron alloy is not particularly limited, and examples include Fe-Si-based alloys, Fe-Si-Cr-based alloys, Fe-Si-Al-based alloys, etc. The alloy may further contain B, C, etc. as other sub-components. The content of the sub-components is not particularly limited, but may be, for example, 0.1 mass% or more and 5.0 mass% or less, preferably 0.5 mass% or more and 3.0 mass% or less. The metal magnetic material may be only one type or two or more types. The iron alloy is not particularly limited, and examples include Fe-Si-based alloys, Fe-Si-Cr-based alloys, Fe-Si-Al-based alloys, etc.

[0016] In a preferred embodiment, the metal magnetic material is an Fe-Si alloy or an Fe-Si-Cr alloy. When an Fe-Si alloy is used as the metal magnetic powder, the Si content is preferably 2.0 at% or more and 8.0 at% or less. When an Fe-Si-Cr alloy is used, the Si content is preferably 2.0 at% or more and 8.0 at% or less, and the Cr content is preferably 0.2 at% or more and 6.0 at% or less.

[0017] The above metal magnetic particles may contain impurity components such as Cr, Mn, Cu, Ni, P, and S. These impurity components are not intentionally added, and their content can be, for example, 1 mass% or less, preferably 0.1 mass% or less.

[0018] The above metal magnetic particles preferably have an average particle size of 0.5 μm or more and 50 μm or less, more preferably 1 μm or more and 30 μm or less, and even more preferably 2 μm or more and 20 μm or less. By setting the average particle size of the above metal magnetic particles to 0.5 μm or more, the handling of the metal magnetic particles becomes easy. Further, by setting the average particle size of the above metal magnetic particles to 50 μm or less, it becomes possible to increase the packing ratio of the metal magnetic particles, and the magnetic properties of the magnetic layer are improved.

[0019] Here, the above average particle size means the average of the equivalent circle diameters of the metal magnetic particles in the SEM (scanning electron microscope) image of the cross-section of the magnetic layer. For example, the above average particle size is obtained by cutting the laminated coil component 1 to obtain a cross-section, photographing a plurality of regions (for example, 5 regions) (for example, 130 μm × 100 μm) at a plurality of locations (for example, 5 locations) with SEM, and analyzing this SEM image using image analysis software (for example, A Image-kun (registered trademark) manufactured by Asahi Kasei Engineering Co., Ltd.), obtaining the equivalent circle diameters for 500 or more metal particles, and calculating their average.

[0020] The above metal magnetic particles preferably have an oxide film.

[0021] The oxide film can be an oxide film of the metal constituting the metal magnetic particles, that is, a self-generated oxide film.

[0022] The thickness of the oxide film is not particularly limited, but is preferably 1 nm or more and 100 nm or less, more preferably 3 nm or more and 50 nm or less, still more preferably 5 nm or more and 30 nm or less, and can be, for example, 10 nm or more and 30 nm or less or 5 nm or more and 20 nm or less. By increasing the thickness of the oxide film, the resistivity of the magnetic layer is improved. Also, by reducing the thickness of the oxide film, the amount of metal magnetic particles in the magnetic layer can be increased more, the magnetic properties of the magnetic layer are improved, and it becomes easier to miniaturize the magnetic layer.

[0023] The metal magnetic particles are bonded by the oxide film.

[0024] The metal magnetic particles may be insulated by an insulating film. The insulating film can be a film other than the oxide film.

[0025] The insulating film is preferably a film containing a metal oxide, and more preferably a film of an oxide of Si.

[0026] Examples of the method for forming the insulating film include a mechanochemical method and a sol-gel method. In particular, when forming a film of an oxide of Si, the sol-gel method is preferable. When forming a film containing an oxide of Si by the sol-gel method, a sol-gel coating agent containing Si alkoxide and an organic chain-containing silane coupling agent are mixed, this mixed solution is adhered to the surface of the metal magnetic particles, dehydrated and bonded by heat treatment, and then dried at a predetermined temperature to form it.

[0027] The insulating film may cover only a part of the surface of the metal magnetic particles, or may cover the entire surface. Further, the shape of the insulating film is not particularly limited, and may be a mesh shape or a layered shape. In a preferred embodiment, in the above metal magnetic particles, 50% or more, preferably 70% or more, more preferably 80% or more, still more preferably 90% or more, and particularly preferably 100% of the surface area is covered by the insulating film. By covering the surface of the metal particles with the insulating film, the specific resistance inside the magnetic layer can be increased.

[0028] The thickness of the insulating film is not particularly limited, but is preferably 1 nm or more and 100 nm or less, more preferably 3 nm or more and 50 nm or less, still more preferably 5 nm or more and 30 nm or less, and may be, for example, 10 nm or more and 30 nm or less, or 5 nm or more and 20 nm or less. By increasing the thickness of the insulating film, the specific resistance inside the magnetic layer can be increased. Further, by reducing the thickness of the insulating film, the amount of metal magnetic particles in the magnetic layer can be increased, the magnetic properties of the magnetic layer can be improved, and the miniaturization of the magnetic layer can be easily achieved.

[0029] In addition to the magnetic layer, the base body 2 may have a non-magnetic layer.

[0030] The non-magnetic layer is preferably provided between the internal electrode layers.

[0031] By providing the non-magnetic layer, the DC superposition characteristics of the multilayer coil component are improved, and the insulation between the internal electrodes is improved.

[0032] The non-magnetic layer is preferably composed of a sintered non-magnetic material containing at least Fe, Cu, and Zn as main components.

[0033] In the above sintered non-magnetic material, the Fe content is Fe 2 O 3In terms of conversion to, it is preferably 40.0 mol% or more and 49.5 mol% or less (based on the total of the main components, the same applies hereinafter), and more preferably 45.0 mol% or more and 49.5 mol% or less.

[0034] In the above sintered non-magnetic material, the Cu content, in terms of CuO, is preferably 4.0 mol% or more and 12.0 mol% or less (based on the total of the main components, the same applies hereinafter), and more preferably 6.0 mol% or more and 10.0 mol% or less.

[0035] In the above sintered non-magnetic material, the Zn content is not particularly limited and can be the balance of Fe and Cu, which are the other main components described above. In terms of ZnO, it is preferably 39.5 mol% or more and 56.0 mol% or less (based on the total of the main components, the same applies hereinafter), and more preferably 40.5 mol% or more and 49.0 mol% or less.

[0036] By setting the contents of Fe, Cu, and Zn within the above ranges, excellent electrical properties can be obtained.

[0037] In the present disclosure, the above sintered non-magnetic material may further contain additive components. Examples of the additive components in the sintered non-magnetic material include, but are not limited to, Mn, Co, Sn, Bi, Si, etc. The contents (addition amounts) of Mn, Co, Sn, Bi, and Si are, respectively, based on 100 parts by mass of the total of the main components (Fe (converted to Fe 2 O 3 converted), Zn (converted to ZnO), Cu (converted to CuO), and Ni (converted to NiO)), Mn 3 O 4 , Co 3 O 4 , SnO 2 , Bi 2 O 3 , and SiO 2 converted, are preferably 0.1 part by mass or more and 1 part by mass or less. Further, the above sintered non-magnetic material may further contain unavoidable impurities in production.

[0038] The thickness of the non-magnetic layer can preferably be 5 μm or more and 180 μm or less, more preferably 10 μm or more and 100 μm or less, and still more preferably 30 μm or more and 100 μm or less.

[0039] The coil 3 is formed by connecting a plurality of internal electrode layers 3a to 3e with via conductors 3p to 3s.

[0040] The internal electrode layer contains a conductive material. The conductive material includes silver, copper, gold, or an alloy thereof. The internal electrode layer preferably contains silver as the conductive material, and more preferably contains only silver.

[0041] The thickness of the internal electrode layer is not particularly limited, but is preferably 15 μm or more and 150 μm or less, and more preferably 20 μm or more and 40 μm or less.

[0042] The lead-out portions 4a and 4b electrically connect the ends of the coil 3 and the bottom electrodes 5a and 5b. In the present embodiment, the lead-out portion 4a connects the internal electrode layer 3a at the lower end of the coil and the bottom electrode 5a, and the lead-out portion 4b connects the internal electrode layer 3e at the upper end of the coil and the bottom electrode 5b. The lead-out portion 4b is longer than the lead-out portion 4a.

[0043] The lead-out portions 4a and 4b preferably contain the same conductive material as the internal electrode layer. The conductive material includes silver, copper, gold, or an alloy thereof. The lead-out portions 4a and 4b preferably contain silver as the conductive material, and more preferably contain only silver.

[0044] The insulating layer 7 is provided on the bottom surface of the base body 2.

[0045] In the multilayer coil component 1, the insulating layer 7 is provided only on the bottom surface. In other words, the insulating layer 7 does not exist on the upper surface and the side surfaces of the base body 2. Note that, although such a mode is preferable for the coil component of the present disclosure, it is not limited thereto. For example, the insulating layer may be provided on the side surface in addition to the bottom surface, or on the side surface and the upper surface.

[0046] The insulating layer 7 has openings 9a and 9b.

[0047] The openings 9a and 9b are provided so that the bottom electrodes 5a and 5b are exposed. In the openings, preferably, only the bottom electrodes are exposed and the base body 2 is not exposed. In other words, in a plan view from the bottom side of the base body 2, the areas of the openings 9a and 9b are equal to or less than the areas of the bottom electrodes 5a and 5b, and the openings 9a and 9b are located inside the bottom electrodes 5a and 5b. By providing the openings so that the base body 2 is not exposed, it is possible to suppress the plating solution from touching the base body 2 and causing plating growth in the plating process for forming the plating layer.

[0048] The insulating layer 7 is made of a resin material having a higher insulation resistance than the material of the base body 2.

[0049] Examples of the resin material include resin materials with high electrical insulation properties such as acrylic resin, epoxy resin, and polyamide. The resin material may contain a filler made of an insulating material.

[0050] The external electrodes 8a and 8b are provided on the bottom surface of the multilayer coil component 1. The external electrodes 8a and 8b include the bottom electrodes 5a and 5b and plating layers 6a and 6b provided on the bottom electrodes 5a and 5b. The bottom electrodes 5a and 5b are provided inside the base body 2, and the plating layers 6a and 6b are provided inside the openings 9a and 9b.

[0051] In the multilayer coil component 1, the bottom electrodes 5a and 5b are embedded in the base body 2 with one main surface exposed. Note that the coil component of the present disclosure is not limited to such a mode. For example, only a part of the bottom electrode may be embedded in the bottom surface of the base body, or the bottom electrode may be provided on the bottom surface of the base body.

[0052] In the multilayer coil component 1, the bottom electrodes 5a and 5b extend from the lead-out portions 4a and 4b to substantially the central portion in the W direction of the base body 2 on the bottom surface of the base body 2. Note that the coil component of the present disclosure is not limited to such a mode. For example, the bottom electrode may be provided at the same position as the lead-out portion.

[0053] The bottom electrodes 5a and 5b preferably contain the same conductive material as the internal electrode layer. Examples of the conductive material include silver, copper, gold, or alloys thereof. The bottom electrodes 5a and 5b preferably contain silver as the conductive material, and more preferably contain only silver.

[0054] The plating layers 6a and 6b are provided on the bottom electrodes 5a and 5b within the openings 9a and 9b. The plating layer is preferably provided over the entire opening in a plan view from the bottom side of the base body 2.

[0055] In the multilayer coil component 1, the thickness (length in the T direction) of the plating layers 6a and 6b is smaller than the height (length in the T direction) of the openings 9a and 9b. That is, the plating layers 6a and 6b are recessed from the bottom surface of the insulating layer 7. In other words, the multilayer coil component 1 has a recess on the bottom surface defined by the side surfaces of the openings and the plating layers. Note that the coil component of the present disclosure is not limited to such a mode. For example, the plating layer may completely fill the opening. In one mode, the plating layer may be provided flush with the insulating layer. In another mode, the plating layer may be provided so as to protrude from the insulating layer.

[0056] The plating layers 6a and 6b may be a single layer or a multilayer.

[0057] The plating layers 6a and 6b may preferably include a plating layer containing Cu, a plating layer containing Ni, a plating layer containing Sn, and a Au plating layer.

[0058] In one mode, the plating layers 6a and 6b may be a Cu plating layer, a Ni - Sn plating layer, a Ni - Au plating layer, a Ni - Cu plating layer, or a Cu - Ni - Au plating layer on the bottom electrode.

[0059] As described above, the multilayer coil component of the present disclosure has been described with reference to embodiments, but the multilayer coil component of the present disclosure is not limited to the above embodiments, and various modifications are possible.

[0060] Next, a method for manufacturing the laminated coil component of the present disclosure will be described.

[0061] The laminated coil component of the present disclosure can be obtained by laminating a magnetic paste, a non-magnetic paste, and an internal conductor paste and then heat-treating the laminate.

[0062] Specifically, the laminated coil component 1 can be manufactured as follows.

[0063] As the magnetic paste, a magnetic paste containing metal magnetic particles is prepared. The metal magnetic particles are mixed with cellulose, polyvinyl butyral, etc. as binders and a mixture of terpineol, butyl diglycol acetate, etc. as solvents, and kneaded to obtain a magnetic paste.

[0064] As the non-magnetic paste, a non-magnetic paste containing a ferrite material is prepared. As the ferrite material, Fe 2 O 3 , ZnO, CuO, and, if necessary, additive components are weighed to have a predetermined composition, and the weighed materials are put into a ball mill together with pure water, a dispersant, and PSZ media, and mixed and pulverized. The obtained slurry is dried and calcined at a temperature of 700 to 800 °C for 2 to 3 hours. A predetermined amount of a solvent (such as a ketone-based solvent), a resin (such as polyvinyl acetal), and a plasticizer (such as an alkyd-based plasticizer) are added to the obtained non-magnetic ferrite material (calcined powder), kneaded with a planetary mixer, and then further dispersed with a three-roll mill to produce a non-magnetic ferrite paste.

[0065] As the conductor paste, a conductor paste, for example, a silver paste, is prepared. The conductor paste is obtained by mixing conductor powder with a predetermined amount of a solvent, a resin, a dispersant, etc.

[0066] Next, a laminate of the above pastes is produced.

[0067] Prepare a substrate (not shown) with a thermal release sheet and a polyethylene terephthalate (PET) film stacked on a metal plate, and screen-print a magnetic paste thereon a predetermined number of times to form a magnetic paste layer 21. The obtained magnetic paste layer 21 becomes the outer layer of the coil component. (Fig. 7(a))

[0068] Next, a conductor paste layer 31 that becomes a coil conductor is formed on the magnetic paste layer 21. Further, a magnetic paste layer 22 is formed in a region where the conductor paste layer 31 is not formed. (Fig. 7(b))

[0069] Next, a non-magnetic ferrite paste layer 81 is formed on the conductor paste layer 31 in a region other than the region connected to the coil conductor to be printed next and the region connected to the lead-out conductor. Next, a magnetic paste layer 23 is formed in a region other than the non-magnetic ferrite paste layer 81. (Fig. 7(c))

[0070] Next, a conductor paste layer 32 that becomes a via conductor (a conductor connected to the coil conductor to be printed next) and a conductor paste layer 41 that becomes a lead-out conductor are formed. (Fig. 7(d))

[0071] Next, a conductor paste layer 33 that becomes a coil conductor and a conductor paste layer 42 that becomes a lead-out conductor are formed. Further, a magnetic paste layer 24 is formed in a region where the conductor paste layers 33 and 42 are not formed. (Fig. 7(e))

[0072] Next, a non-magnetic ferrite paste layer 82 is formed on the conductor paste layer 33 in a region other than the region connected to the coil conductor to be printed next. Also, a conductor paste layer 34 that becomes a via conductor is formed in the region connected to the coil conductor to be printed next, and a conductor paste layer 43 that becomes a lead-out conductor is formed. Further, a magnetic paste layer 25 is formed in a region other than these regions. (Fig. 7(f))

[0073] Repeat the steps of Figs. 7(e) and (f) a predetermined number of times to obtain a laminate in which a magnetic paste layer 26, a conductor paste layer 35, and a conductor paste layer 44 are formed. (Fig. 7(g))

[0074] Next, conductor paste layers 45 and 46 are printed at locations to become lead-out conductors, and a magnetic paste layer 27 is printed in other regions (Fig. 7(h)). This is repeated a predetermined number of times to obtain a laminate in which magnetic paste layers 28 and conductor paste layers 47 and 48 are formed. (Fig. 7(i))

[0075] Next, conductor paste layers 51 and 52 are formed in regions to become bottom electrodes of the external electrodes, and a magnetic paste layer 29 is formed in regions where the conductor paste layers 51 and 52 are not formed. (Fig. 7(j))

[0076] Finally, it is peeled from the metal plate, the PET film is removed, and a block of the laminate is produced.

[0077] The obtained laminate block is subjected to a pressure treatment, for example, a warm isostatic pressing (WIP) treatment.

[0078] The pressure-treated laminate block is degreased, placed in a firing furnace, and fired.

[0079] The temperature of the above firing is preferably 600°C or higher and 800°C or lower, more preferably 650°C or higher and 750°C or lower.

[0080] The time of the above firing is preferably 30 minutes or longer and 90 minutes or shorter, more preferably 40 minutes or longer and 80 minutes or shorter.

[0081] The above firing is preferably carried out in the air.

[0082] The fired laminate block is impregnated with resin and thermally cured. As the resin, an epoxy resin is preferably used.

[0083] Regarding the laminate block impregnated with resin, a resist resin having photosensitivity is applied to the entire surface of the surface (lower surface) where the bottom electrode is exposed by screen printing and then dried to obtain an insulating layer 7. (Fig. 8(a))

[0084] After performing pattern exposure along the shape of the bottom electrode, immerse it in a developer to remove the insulating layer on the bottom electrode. (Fig. 8(b))

[0085] Next, perform electroless plating to form a plating layer on the bottom electrode. (Fig. 8(c))

[0086] Next, cut the laminate block with a dicing saw or the like to individualize or array it.

[0087] In the above manner, the laminated coil component 1 can be obtained.

Industrial Applicability

[0088] The laminated coil component of the present invention can be widely used in various applications as an inductor or the like.

Explanation of Signs

[0089] 1... laminated coil component; 2... body; 3... coil; 3a, b, c, d, e... internal electrode layers; 3p, q, r, s... via conductors; 4a, b... lead-out portions; 5a, b... bottom electrodes; 6a, b... plating layers; 7... insulating layer; 8a, b... external electrodes; 9a, b... openings; 21... magnetic paste layer; 22... magnetic paste layer; 23... magnetic paste layer; 24... magnetic paste layer; 25... magnetic paste layer; 26... magnetic paste layer; 27... magnetic paste layer; 28... magnetic paste layer; 29... magnetic paste layer; 31... conductor paste layer; 32... conductor paste layer; 33... conductor paste layer; 34... conductor paste layer; 35... conductor paste layer; 41... conductor paste layer; 42... conductor paste layer; 43... conductor paste layer; 44... conductor paste layer; 45... conductor paste layer; 46... conductor paste layer; 47... conductor paste layer; 48... conductor paste layer; 51... conductor paste layer; 52... conductor paste layer; 81... non-magnetic ferrite paste layer; 82... non-magnetic ferrite paste layer

Claims

1. A laminated coil component having a magnetic layer containing metal magnetic particles and an internal electrode layer laminated, a body in which a coil is formed inside, an external electrode electrically connected to the coil, an insulating layer provided on the bottom surface of the body, wherein the external electrode has a main surface, and includes a bottom electrode embedded in the body so that the main surface is exposed from the bottom surface of the body, the insulating layer has an opening exposing at least a part of the main surface exposed from the bottom surface of the body, the external electrode includes a plating layer provided on the bottom electrode at the opening, in a plan view from the bottom surface side of the body, the area of the opening is equal to or less than the area of the bottom electrode, coil component.

2. The coil component according to claim 1, wherein the plating layer is provided flush with the insulating layer.

3. The coil component according to claim 1, wherein the plating layer is recessed from the bottom surface of the insulating layer.

4. The coil component according to claim 1, wherein the plating layer is provided so as to protrude from the insulating layer.

5. The coil component according to any one of claims 1 to 4, wherein the plating layer is a Cu layer, a Ni—Sn layer, a Ni—Au layer, a Ni—Cu layer, or a Cu—Ni—Au layer.

6. The coil component according to any one of claims 1 to 5, wherein the insulating layer is a resin material having a higher insulation resistance than the body.

7. A method for manufacturing a laminated coil component having a magnetic layer containing metal magnetic particles and an internal electrode layer laminated, a body in which a coil is formed inside, a coil embedded in the body, an external electrode electrically connected to the coil and provided on the bottom surface of the body, and an insulating layer provided on the bottom surface of the body, the method comprising: laminating a magnetic paste layer and a conductor paste layer so that the surface of the conductor paste layer serving as the bottom electrode and the surface of the magnetic paste layer are exposed on the bottom surface, and firing to produce a laminated body block; forming the insulating layer on the surface of the fired laminated body block where the bottom electrode is exposed so as to expose at least a partial region of the bottom electrode and have an opening having an area equal to or less than the area of the bottom electrode in a plan view from the bottom surface side of the body; forming a plating layer on the bottom electrode at the opening; cutting the laminated body block, wherein the method includes the steps of manufacturing a coil component. ​

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