Manufacturing method of laminated coil component and laminated coil component

Abstract

To provide a manufacturing method of a laminated coil component and a laminated coil component capable of uniforming the thickness of a terminal electrode.SOLUTION: A manufacturing method of a laminated coil component 1 includes the steps of forming an insulator layer 10, forming a first coil conductor 20, a second coil conductor 21, a third coil conductor 22 and a fourth coil conductor 23, obtaining a laminate L formed by laminating the insulator layer 10 and the first coil conductor 20, the second coil conductor 21, the third coil conductor 22 and the fourth coil conductor 23, and forming terminal electrodes 4 and 5 on the outer surface of the laminate L by photolithography.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a laminated coil component and a laminated coil component. [Background technology]

[0002] A known conventional method for manufacturing a laminated coil component is described in, for example, Patent Document 1. The method for manufacturing a laminated coil component described in Patent Document 1 includes the following steps: a first step of forming an unfired laminate by photolithography, the unfired laminate being formed by laminating insulating layers and internal electrodes on a peelable base; a second step of cutting the laminate into multiple chips, peeling off the base, and firing each chip; and a third step of forming external electrodes on both ends of each fired chip. In the third step, both ends of the fired chip are dipped in a conductive paste and baked, and the baked layer is plated to form external electrodes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-177365 Summary of the Invention [Problem to be solved by the invention]

[0004] When external electrodes are formed by the dipping method, in which the element body (chip) is dipped in conductive paste, as in conventional manufacturing methods for multilayer coil components, the thickness of the external electrodes can become uneven. In particular, the thickness of the external electrodes at the corners of the element body becomes thinner than in other parts. When the thickness of the external electrodes becomes uneven, it can lead to poor appearance, reduced yields, and peeling of the plating.

[0005] An object of one aspect of the present invention is to provide a method for manufacturing a laminated coil component and a laminated coil component that can make the thickness of terminal electrodes uniform. [Means for solving the problem]

[0006] A method for manufacturing a laminated coil component according to one aspect of the present invention includes the steps of forming an insulator layer, forming a coil conductor, obtaining a laminate formed by stacking the insulator layers and the coil conductors, and forming terminal electrodes on the outer surface of the laminate by photolithography.

[0007] In a manufacturing method of a laminated coil component according to one aspect of the present invention, terminal electrodes are formed on the outer surfaces of the laminate by photolithography. Photolithography allows the terminal electrodes to be formed with high precision. Therefore, by forming the terminal electrodes by photolithography, the thickness of the terminal electrodes can be made uniform.

[0008] In one embodiment, the method includes forming a laminate substrate including a plurality of laminates and singulating the laminate substrate into individual laminates, and the step of forming terminal electrodes may include forming the terminal electrodes on the singulated laminates. In a method of forming the terminal electrodes and then cutting the terminal electrodes into individual laminates, a large cutting stress is applied to the terminal electrodes when the terminal electrodes are cut by dicing or the like, which may result in deformation of the terminal electrodes. This may result in uneven thickness of the terminal electrodes. In a method of manufacturing a laminated coil component, the terminal electrodes are formed on the singulated laminates, thereby avoiding deformation due to cutting. Therefore, the thickness of the terminal electrodes can be made uniform.

[0009] A laminated coil component according to one aspect of the present invention includes an element body formed by laminating a plurality of insulator layers, a coil disposed within the element body and configured to include a plurality of coil conductors, and a terminal electrode disposed on an outer surface of the element body and formed by photolithography, wherein, when the maximum thickness of the terminal electrode is a and the minimum thickness is b, (b / a)≧0.7 Satisfy the relationship.

[0010] In a laminated coil component according to one aspect of the present invention, the terminal electrodes satisfy the above relationship, thereby making it possible to make the thickness of the terminal electrodes uniform in the laminated coil component.

[0011] In one embodiment, a bonding conductor may be provided that is disposed within the element body, is exposed on an outer surface of the element body facing the terminal electrode, and is bonded to the terminal electrode. This configuration can improve the bonding strength between the element body and the terminal electrode.

[0012] In one embodiment, a plurality of the joining conductors may be provided in series, which can further increase the joining strength between the element body and the terminal electrode.

[0013] In one embodiment, the element body has, as outer surfaces, a pair of end faces facing each other, a pair of main faces facing each other, and a pair of side faces facing each other, one of the main faces being a mounting surface, the terminal electrodes having a first electrode portion disposed on the end faces and a second electrode portion disposed on the mounting surface, and having an L-shape when viewed from the opposing direction of the pair of side faces, when the curvature of a corner of the first electrode portion away from the end faces is R1, the curvature of a corner of the second electrode portion away from the mounting surface is R2, and the curvature of a corner formed by the first electrode portion and the second electrode portion is R3, R1=R2≧R3 In this configuration, by satisfying this relationship, the thickness of the terminal electrodes can be made uniform. [Effects of the Invention]

[0014] According to one aspect of the present invention, the thickness of the terminal electrodes can be made uniform. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing a laminated coil component according to one embodiment. [Figure 2] FIG. 2 is a side view of the laminated coil component of FIG. [Figure 3]FIG. 3 is an exploded perspective view of the element body shown in FIG. [Figure 4] FIG. 4 is a diagram showing a method for manufacturing a laminated coil component. [Figure 5] FIG. 5 is a diagram illustrating a method for manufacturing a laminated coil component. [Figure 6] FIG. 6 is a side view of a laminated coil component according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are designated by the same reference numerals, and redundant description will be omitted.

[0017] [Multilayer coil components] Fig. 1 is a perspective view of a laminated coil component according to one embodiment. Fig. 2 is a side view of the laminated coil component. As shown in Figs. 1 and 2, the laminated coil component 1 includes a rectangular parallelepiped element body 2 and a plurality of (here, a pair of) terminal electrodes 4, 5. The pair of terminal electrodes 4, 5 is disposed at both ends of the element body 2. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges.

[0018] The element body 2 has, as its outer surfaces, a pair of end faces 2a, 2b facing each other, a pair of main faces 2c, 2d facing each other, and a pair of side faces 2e, 2f facing each other. Hereinafter, the facing direction in which the pair of main faces 2c, 2d face each other will be referred to as a first direction D1, the facing direction in which the pair of end faces 2a, 2b face each other will be referred to as a second direction D2, and the facing direction in which the pair of side faces 2e, 2f face each other will be referred to as a third direction D3. In this embodiment, the first direction D1 is the height direction of the element body 2. The second direction D2 is the length direction of the element body 2 and is perpendicular to the first direction D1. The third direction D3 is the width direction of the element body 2 and is perpendicular to the first direction D1 and the second direction D2.

[0019] The pair of end faces 2a, 2b extend in a first direction D1 so as to connect the pair of principal faces 2c, 2d together. The pair of end faces 2a, 2b also extend in a third direction D3, i.e., in the direction of the short sides of the pair of principal faces 2c, 2d. The pair of side faces 2e, 2f also extend in the first direction D1 so as to connect the pair of principal faces 2c, 2d together. The pair of side faces 2e, 2f also extend in a second direction D2, i.e., in the direction of the long sides of the pair of principal faces 2c, 2d. The laminated coil component 1 is mounted on an electronic device (e.g., a circuit board or an electronic component) by, for example, soldering. In the laminated coil component 1, the principal face 2c forms a mounting surface that faces the electronic device.

[0020] As shown in FIG. 3, the element body 2 is constructed by stacking multiple element body layers 6 in the third direction D3. The element body 2 has multiple stacked element body layers 6. In the element body 2, the stacking direction in which the multiple element body layers 6 are stacked coincides with the third direction D3. As will be described later, some element body layers 6 are formed integrally with adjacent element body layers 6 in the stacking direction. Even for each element body layer 6 formed as a separate body, in the actual element body 2, the boundaries between each element body layer 6 are integrated to the extent that they are not visible.

[0021] Each element layer 6 includes, for example, an insulating material. Each element layer 6 includes, for example, a magnetic material as the insulating material. Examples of magnetic materials include Ni-Cu-Zn ferrite material, Ni-Cu-Zn-Mg ferrite material, Ni-Cu ferrite material, or an Fe alloy. Each element layer 6 may include, for example, a non-magnetic material as the insulating material. Examples of non-magnetic materials include a glass ceramic material or a dielectric material. Each element layer 6 may be formed, for example, through a firing process in which an insulator layer including an insulating material is fired, and may include a sintered body of the insulating material.

[0022] As shown in FIG. 1 , the pair of terminal electrodes 4, 5 are spaced apart from each other in the second direction D2. When viewed from the third direction D3, the terminal electrodes 4, 5 are L-shaped. Each of the terminal electrodes 4, 5 contains, for example, a conductive material. The conductive material contains, for example, Ag or Pd. The conductive material contains, for example, a metal powder such as Ag powder or Pd powder. A plating layer may be formed on the surface of each of the terminal electrodes 4, 5. The plating layer is formed, for example, by electroplating or electroless plating. The plating layer contains, for example, Ni, Sn, or Au.

[0023] The terminal electrode 4 is arranged on the end face 2a side of the element body 2. The terminal electrode 4 is arranged across the end face 2a and the main face 2c. The terminal electrode 4 has a first electrode portion 4a provided on the end face 2a and a second electrode portion 4b provided on the main face 2c. The first electrode portion 4a and the second electrode portion 4b are integrally formed with each other. The first electrode portion 4a and the second electrode portion 4b are connected to each other at the ridge portion of the element body 2 and are electrically connected to each other.

[0024] The first electrode portion 4a extends along the first direction D1. The first electrode portion 4a has a rectangular shape when viewed from the second direction D2. The second electrode portion 4b extends along the second direction D2. The second electrode portion 4b has a rectangular shape when viewed from the first direction D1. The first electrode portion 4a and the second electrode portion 4b extend along the third direction D3.

[0025] The terminal electrode 5 is arranged on the end face 2b side of the element body 2. The terminal electrode 5 is arranged across the end face 2b and the main face 2c. The terminal electrode 5 has a first electrode portion 5a provided on the end face 2b and a second electrode portion 5b provided on the main face 2c. The first electrode portion 5a and the second electrode portion 5b are integrally formed with each other. The first electrode portion 5a and the second electrode portion 5b are connected to each other at the ridge portion of the element body 2 and are electrically connected to each other.

[0026] The first electrode portion 5a extends along a first direction D1. The first electrode portion 5a has a rectangular shape when viewed from a second direction D2. The second electrode portion 5b extends along the second direction D2. The second electrode portion 5b has a rectangular shape when viewed from the first direction D1. The first electrode portion 5a and the second electrode portion 5b extend along a third direction D3.

[0027] The terminal electrodes 4 and 5 satisfy the following relationship, where a is the maximum thickness of the terminal electrodes 4 and 5 and b is the minimum thickness of the terminal electrodes 4 and 5. (b / a)≧0.7 The maximum thickness a and the minimum thickness b are the distances between the outer surfaces (end faces 2a, 2b, main face 2c) of the element body 2 and the outer surfaces of the terminal electrodes 4, 5 in the first direction D1 or the second direction D2. For convenience, in FIG. 2, the thickness of the first electrode portion 5a is indicated as a and the thickness of the second electrode portion 5b is indicated as b. The maximum thickness a may be the first electrode portions 4a, 5a or the second electrode portions 4b, 5b. The minimum thickness b may be the first electrode portions 4a, 5a or the second electrode portions 4b, 5b.

[0028] In the terminal electrodes 4 and 5, when viewed from the third direction D3, the curvature of the first corner C1 in the first electrode portion 4a and 5a that is separated from the end faces 2a and 2b is R1, the curvature of the second corner C2 in the second electrode portion 4b and 5b that is separated from the main surface 2c is R2, and the curvature of the third corner C3 formed by the first electrode portion 4a and 5a and the second electrode portion 4b and 5b is R3, the following relationship is satisfied. R1=R2≧R3 That is, the curvatures R1 and R2 are the same, and the curvatures R1 and R2 are equal to or greater than the curvature R3. Specifically, the first corner C1 is a corner located in the first electrode portion 4a, 5a and spaced apart from the end faces 2a, 2b in the second direction D2, and is formed by a surface that does not contact the end faces 2a, 2b and extends along the first direction D1, and a surface located on the principal surface 2d side and extends along the second direction D2. Specifically, the second corner C2 is a corner located in the second electrode portion 4b, 5b and spaced apart from the principal surface 2c in the first direction D1, and is formed by a surface that does not contact the principal surface 2c and extends along the second direction D2, and a surface located on the end face 2a or end face 2b side and extends along the first direction D1.

[0029] 2, the laminated coil component 1 includes a coil 7 disposed within the element body 2. The coil axis of the coil 7 extends along the third direction D3. The outer shape of the coil 7 is substantially rectangular when viewed from the third direction D3.

[0030] As shown in FIG. 3, the coil 7 (see FIG. 2) includes a first coil conductor 20, a second coil conductor 21, a third coil conductor 22, and a fourth coil conductor 23. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23 are arranged in this order along the third direction D3. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23 each have a substantially rectangular shape with a partially interrupted loop, and each have one end and the other end. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23 each have a portion that extends linearly along the first direction D1 and a portion that extends linearly along the second direction D2. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23 are formed with a predetermined width.

[0031] The first coil conductor 20 is connected to the terminal electrode 5 via a connecting conductor 25. The connecting conductor 25 is located in the same layer as the first coil conductor 20. One end of the first coil conductor 20 is connected to the connecting conductor 25. The connecting conductor 25 connects the first coil conductor 20 to the first electrode portion 5a of the terminal electrode 5. The connecting conductor 25 may be connected to the second electrode portion 5b. The first coil conductor 20 and the connecting conductor 25 are integrally formed.

[0032] The second coil conductor 21 is connected to the first coil conductor 20. A portion of the first coil conductor 20 and a portion of the second coil conductor 21 overlap when viewed from the third direction D3. The third coil conductor 22 is connected to the second coil conductor 21. A portion of the second coil conductor 21 and a portion of the third coil conductor 22 overlap when viewed from the third direction D3.

[0033] The fourth coil conductor 23 is connected to the third coil conductor 22. A portion of the third coil conductor 22 and a portion of the fourth coil conductor 23 overlap when viewed from the third direction D3. The fourth coil conductor 23 is connected to the terminal electrode 4 via a connecting conductor 26. The connecting conductor 26 is located in the same layer as the fourth coil conductor 23. One end of the fourth coil conductor 23 is connected to the connecting conductor 26. The connecting conductor 26 connects the fourth coil conductor 23 to the first electrode portion 4a of the terminal electrode 4. The connecting conductor 26 may be connected to the second electrode portion 4b. The fourth coil conductor 23 and the connecting conductor 26 are integrally formed.

[0034] The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23 constitute the coil 7 (see FIG. 2). The coil 7 is electrically connected to the terminal electrode 5 through a connecting conductor 25. The coil 7 is electrically connected to the terminal electrode 4 through a connecting conductor 26.

[0035] The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, the fourth coil conductor 23, and the connecting conductors 25, 26 contain a conductive material. The conductive material includes Ag or Pd. The conductive material includes, for example, a metal powder such as Ag powder or Pd powder. In this embodiment, the first coil conductor 20, the second coil conductor 21, the third coil conductor 22, the fourth coil conductor 23, and the connecting conductors 25, 26 contain the same conductive material as the terminal electrodes 4, 5. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, the fourth coil conductor 23, and the connecting conductors 25, 26 may contain a conductive material different from that of the terminal electrodes 4, 5. The first coil conductor 20, the second coil conductor 21, the third coil conductor 22, the fourth coil conductor 23, and the connecting conductors 25, 26 are provided on the corresponding element layers 6.

[0036] [Manufacturing method for multilayer coil components] Next, a description will be given of a method for manufacturing the laminated coil component 1. The method for manufacturing the laminated coil component 1 includes a step of forming the laminate substrate 30, a step of dividing the plurality of laminates L into individual pieces, and a step of forming the terminal electrodes 4 and 5.

[0037] The step of forming the laminate substrate 30 will be described. In the step of forming the laminate substrate 30, the laminate substrate 30 is formed as shown in FIG. 4. The laminate substrate 30 is formed by stacking a plurality of insulator layers 10. The laminate substrate 30 includes a plurality of laminates L. The laminates L correspond to the laminated coil component 1. The laminates L may be formed into the laminated coil component 1 as they are without undergoing a firing step, or may be formed into the laminated coil component 1 after undergoing a firing step.

[0038] In this embodiment, the number of laminates L is "4". The laminate substrate 30 is formed on a base material 32. When viewed from the stacking direction, the plurality of laminates L are arranged in a first direction D1 and a second direction D2 that intersect with the stacking direction. The plurality of laminates L are formed integrally with the portions (cut portions, divided portions) that are removed during singulation.

[0039] The laminate L has conductors 12 corresponding to the first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23, and the connecting conductors 25 and 26, and an insulator layer 10 corresponding to the element layer 6. The conductors 12 may be directly formed into the first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23, and the connecting conductors 25 and 26 without undergoing a firing process, or may be formed into the first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23, and the connecting conductors 25 and 26 after undergoing a firing process. The insulator layer 10 may be directly formed into the element layer 6 without undergoing a firing process, or may be formed into the element layer 6 after undergoing a firing process.

[0040] In this embodiment, the laminate substrate 30 is manufactured using a photolithography method. The "photolithography method" in this embodiment is not limited to a specific type of mask, as long as it processes a layer containing a photosensitive material into a desired pattern by exposing and developing the layer.

[0041] First, an insulating material is applied to the substrate 32 to form one layer of the insulator layer 10. Next, conductors 12 corresponding to the first coil conductor 20 and the connecting conductor 25 are formed on the insulator layer 10. The conductors 12 are formed using a photolithography method. Specifically, a photosensitive silver paste (photosensitive conductive paste) is applied to the insulator layer 10. Next, the photosensitive silver paste is exposed to ultraviolet light through a mask (e.g., a Cr mask) having the pattern of the conductors 12, and is developed with a developer to form the conductors 12.

[0042] Next, one layer of the insulator layer 10 is formed. The insulator layer 10 is formed around the conductor 12. The insulator layer 10 is formed using a photolithography method. Specifically, a photosensitive insulator paste is applied onto the insulator layer 10 and the conductor 12. That is, the photosensitive insulator paste is applied so as to cover the entire area of ​​the conductor 12. Next, the photosensitive insulator paste is exposed to ultraviolet light through a mask having the pattern of the conductor 12, and is developed with a developer to form the insulator layer 10.

[0043] By the above-described method, the second coil conductor 21, the third coil conductor 22, the fourth coil conductor 23, the conductor 12 corresponding to the connecting conductor 26, and the plurality of insulator layers 10 are formed to form the laminate substrate 30.

[0044] Next, a process of singulating the plurality of laminates L will be described. In the process of singulating the plurality of laminates L, the laminates L are singulated by, for example, dicing. Specifically, the laminate substrate 30 is cut along the first direction D1 and the second direction D2. A dicing blade passes at least between adjacent laminates L in the first direction D1 and between adjacent laminates L in the second direction D2. This causes the laminate substrate 30 to be divided into the plurality of laminates L. By dividing the laminate substrate 30, grooves are formed between adjacent laminates L on the base material 32. Note that the laminates L may be singulated by other methods. For example, the laminate substrate 30 may be cut using a laser, or portions other than the laminates L may be removed by photolithography.

[0045] Next, the process of forming the terminal electrodes 4, 5 will be described. The terminal electrodes 4, 5 are formed using photolithography. In the process of forming the terminal electrodes 4, 5, a photosensitive silver paste is applied (filled) into the grooves between the individual laminates L (on the base material 32). Next, the photosensitive silver paste is exposed to ultraviolet light through a mask having the patterns of the terminal electrodes 4, 5 and developed with a developer, thereby forming the terminal electrodes 4, 5 as shown in FIG. 5. As described above, the laminate L on which the terminal electrodes 4, 5 are formed may be directly formed into the laminated coil component 1 without undergoing a firing process, or may be formed into the laminated coil component 1 after undergoing a firing process. If necessary, the terminal electrodes 4, 5 may be subjected to electrolytic plating or electroless plating to provide a plating layer.

[0046] As described above, in the manufacturing method of the laminated coil component 1 according to this embodiment, the terminal electrodes 4, 5 are formed on the outer surfaces of the laminate L by photolithography. Photolithography allows the terminal electrodes 4, 5 to be formed with high precision. This allows the terminal electrodes 4, 5 to be formed with desired dimensions. Therefore, by forming the terminal electrodes 4, 5 by photolithography, the thickness of the terminal electrodes 4, 5 can be made uniform. As a result, it is possible to avoid a decrease in yield due to poor appearance and peeling of plating.

[0047] Furthermore, in the manufacturing method of the laminated coil component 1, the terminal electrodes 4, 5 are formed by photolithography, which allows the terminal electrodes 4, 5 to be uniformly thin. This makes it possible to reduce the stray capacitance formed between the terminal electrodes 4, 5 and the coil 7. As a result, the self-resonant frequency (SRF) characteristics can be improved (the self-resonant frequency can be shifted to the higher frequency side).

[0048] The manufacturing method of the laminated coil component 1 according to this embodiment includes the steps of forming a laminate substrate 30 including a plurality of laminates L and dicing the laminate substrate 30 into individual laminates L. In the step of forming the terminal electrodes 4, 5, the terminal electrodes 4, 5 are formed on the individual laminates L. In a method in which the terminal electrodes are formed and then cut into individual laminates L, a large cutting stress is applied to the terminal electrodes when the terminal electrodes are cut by dicing, which may result in deformation of the terminal electrodes. This may result in uneven thickness of the terminal electrodes. In the manufacturing method of the laminated coil component 1, the terminal electrodes 4, 5 are formed on the individual laminates L, which prevents deformation due to cutting. This allows the terminal electrodes 4, 5 to have a uniform thickness.

[0049] In the laminated coil component 1 according to this embodiment, when the maximum thickness of the terminal electrodes 4 and 5 is a and the minimum thickness is b, (b / a)≧0.7 This satisfies the relationship: As a result, in the laminated coil component 1, the thicknesses of the terminal electrodes 4 and 5 can be made uniform.

[0050] In the laminated coil component 1 according to this embodiment, the terminal electrodes 4, 5 have first electrode portions 4a, 5a arranged on the end faces 2a, 2b and second electrode portions 4b, 5b arranged on the main surface 2c, and are L-shaped when viewed from the third direction D3. In the laminated coil component 1, when viewed from the third direction D3, if the curvature of a first corner C1 of the first electrode portions 4a, 5a separated from the end faces 2a, 2b is R1, the curvature of a second corner C2 of the second electrode portions 4b, 5b separated from the main surface 2c is R2, and the curvature of a third corner C3 formed by the first electrode portions 4a, 5a and the second electrode portions 4b, 5b is R3, then R1=R2≧R3 In this configuration, by satisfying this relationship, the thickness of the terminal electrodes 4 and 5 can be made uniform.

[0051] Although the embodiments of the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

[0052] In addition to the above-described embodiments, as shown in FIG. 6, the laminated coil component 1A may include a joining conductor 9. The joining conductor 9 is disposed within the element body 2 and exposed on the outer surface of the element body 2 facing the terminal electrodes 4, 5. In the example shown in FIG. 6, the joining conductor 9 is exposed on the end faces 2a, 2b and the main surface 2c. The joining conductor 9 is joined (fixed) to the terminal electrodes 4, 5. The joining conductor 9 includes a conductive material. The conductive material includes Ag or Pd. The conductive material includes, for example, a metal powder such as Ag powder or Pd powder.

[0053] The joining conductor 9 has, for example, a triangular shape when viewed from the third direction D3. The shape of the joining conductor 9 may be rectangular or semicircular. The joining conductor 9 can be formed simultaneously with the coil conductor. Specifically, the joining conductor 9 can be formed by using a mask having patterns corresponding to the coil conductor and the joining conductor 9.

[0054] The joining conductors 9 are arranged continuously (side by side) in the first direction D1 and continuously in the second direction D2. The joining conductors 9 may be arranged independently, or multiple joining conductors 9 may be arranged integrally (connected). The joining conductors 9 may all have the same size, or may have different sizes. The joining conductors 9 may extend along the third direction D3, or may be arranged discontinuously (at intervals) in the third direction D3.

[0055] The laminated coil component 1A includes the joining conductors 9, which can improve the joining strength between the element body 2 and the terminal electrodes 4, 5. Furthermore, by providing a plurality of joining conductors 9 in succession, the joining strength can be further increased.

[0056] In the above embodiment, the terminal electrodes 4, 5 have been described as having the first electrode portions 4a, 5a and the second electrode portions 4b, 5b. However, the configuration of the terminal electrodes 4, 5 is not limited to this. For example, the terminal electrodes 4, 5 may have only the second electrode portions 4b, 5b.

[0057] In the above embodiment, an example has been described in which the terminal electrodes 4, 5 are disposed on the end faces 2a, 2b and main surface 2c of the element body 2. However, the terminal electrodes 4, 5 may be partially embedded in the element body 2. For example, recesses may be formed in the end faces 2a, 2b and main surface 2c of the element body 2, and the terminal electrodes 4, 5 may be partially disposed within the recesses. In this case, the outer surface of the element body 2 refers to the surface on which the recesses are formed.

[0058] In the above embodiment, an example has been described in which the coil 7 is configured by the first coil conductor 20, the second coil conductor 21, the third coil conductor 22, and the fourth coil conductor 23. However, the number of coil conductors configuring the coil 7 is not limited to the above-mentioned value.

[0059] In the above embodiment, an example has been described in which the laminate substrate 30 is formed, and the laminate L is obtained by dividing the laminate substrate 30 into individual laminates L. However, it is also possible to form one laminate L and form the terminal electrodes 4, 5 on this laminate L.

[0060] In the above embodiment, the laminate substrate 30 is formed by photolithography. However, the laminate substrate 30 may be formed by other methods. For example, the laminate substrate 30 may be formed by stacking insulator layers on which coil conductors are formed. [Explanation of symbols]

[0061] 1, 1A... multilayer coil component, 2... element body, 2a, 2b... end face, 2c... main surface (mounting surface), 2d... main surface, 2e, 2f... side face, 4, 5... terminal electrode, 4a, 5a... first electrode portion, 4b, 5b... second electrode portion, 7... coil, 9... joining conductor, 10... insulator layer, 20... first coil conductor, 21... second coil conductor, 22... third coil conductor, 23... fourth coil conductor, 30... laminate substrate, C1... first corner portion, C2... second corner portion, C3... third corner portion, L... laminate, R1, R2, R3... curvature

Claims

1. forming an insulator layer; forming a coil conductor; obtaining a laminate formed by stacking the insulator layers and the coil conductors; forming terminal electrodes on the outer surface of the laminate by photolithography; In the step of forming the terminal electrodes, the terminal electrodes are formed on the outer surfaces of the laminate parallel to the stacking direction of the laminate.

2. forming a laminate substrate including a plurality of the laminates; and separating the plurality of laminates from the laminate substrate, The method for manufacturing a laminated coil component according to claim 1 , wherein in the step of forming the terminal electrodes, the terminal electrodes are formed on the singulated laminate.

3. In the step of forming the terminal electrode, In the terminal electrode, when the maximum thickness is a and the minimum thickness is b, (b / a)≧0.7 3. The method for manufacturing a laminated coil component according to claim 1, wherein the terminal electrodes are formed to satisfy the relationship:

4. A method for manufacturing a laminated coil component as described in claim 2, wherein in the process of forming the coil conductor, a joining conductor is formed, which is placed within a base body obtained by the process of singulating the laminate, and is exposed on the outer surface of the base body facing the terminal electrode, and is joined to the terminal electrode.

5. A method for manufacturing a laminated coil component as described in Claim 4, wherein in the process of forming the coil conductor, multiple joining conductors are provided in succession.

6. The element body obtained by the step of singulating the laminate has, as outer surfaces, a pair of end faces facing each other, a pair of main surfaces facing each other, and a pair of side surfaces facing each other, one of the main surfaces being a mounting surface, In the step of forming the terminal electrode, the terminal electrode is formed to have a first electrode portion disposed on the end surface and a second electrode portion disposed on the mounting surface, and to have an L-shape when viewed from a direction in which the pair of side surfaces face each other, In the step of forming the terminal electrodes, when viewed from the opposing direction, if the curvature of a corner of the first electrode portion that is separated from the end face is R1, the curvature of a corner of the second electrode portion that is separated from the mounting surface is R2, and the curvature of a corner formed by the first electrode portion and the second electrode portion is R3, R1 = R2 ≥ R3 3. The method for manufacturing a laminated coil component according to claim 2, wherein the terminal electrodes are formed to satisfy the relationship:

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