Inductor components

Abstract

To provide an inductor component capable of suppressing generation of a cracking caused by stress remained on a boundary surface between an external part electrode and an element body.SOLUTION: An inductor component 1A comprises: an element body 10; a coil 20; and a first external part electrode 30a. The element body 10 includes: first and second end surfaces 11a and 11b; first and second main surfaces 12a and 12b; and first and second side surfaces. The first external part electrode 30a includes a first electrode layer 31a that is embedded into the element body 10 so that at least one part is exposed from the element body 10. When a first point E1 corresponded to a first ridge part 14a, a second point E2 corresponded to a second ridge part 14b, and a third point E3 that is corresponded to a tip end on the second ridge part 14b side of the first electrode layer 31a positioned at the first main surface 12a are defined in a cross section containing the first electrode layer 31a from a cross rection along a longer direction L and a height direction T are defined, the third point E3 is positioned closer to the second main surface 12b relative to a virtual straight line F connecting the first point E1 with the second point E2.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an inductor component.

Background Art

[0002] Patent Document 1 discloses a laminated inductor having a substantially rectangular parallelepiped-shaped laminate including a plurality of laminated insulating layers and a plurality of internal conductor layers laminated via the insulating layers. In the laminated inductor in which the internal conductor layers are spirally connected to have a coil structure, the coil axis of the coil structure is parallel to the bottom surface of the laminate and perpendicular to the facing direction of a pair of external electrodes formed on the facing end surfaces of the laminate, and the edge portions of the cross section of the internal conductor layer are rounded.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the manufacturing method of the laminated inductor described in Patent Document 1, an insulating sheet printed with a conductor paste for a coil structure and a conductor paste for an external electrode is laminated and then cut into individual pieces to obtain a green laminated inductor. And in the manufacturing method of the laminated inductor described in Patent Document 1, the green laminated inductor is fired to obtain a laminated inductor.

[0005] In the method for manufacturing a multilayer inductor described in Patent Document 1, when firing the green multilayer inductor, it is necessary to simultaneously fire the conductor paste for the external electrodes and the insulating paste for the insulating sheet, which are composed of different materials. Therefore, in the method for manufacturing a multilayer inductor described in Patent Document 1, because the properties such as expansion coefficient and elastic modulus differ between the conductor paste for the external electrodes and the insulating paste for the insulating sheet, stress may remain at the interface between the external electrodes obtained from the conductor paste for the external electrodes and the insulating layer obtained from the insulating sheet in the multilayer inductor obtained by firing the green multilayer inductor. In a multilayer inductor, if stress remains at the interface between the external electrodes and the insulating layer, for example, when mounting the multilayer inductor, if a load (impact) is applied to the multilayer inductor, cracks may occur inside the multilayer inductor starting from the above interface.

[0006] The present invention was made to solve the above-mentioned problems, and aims to provide an inductor component that can suppress the occurrence of cracks caused by residual stress at the interface between the external electrode and the substrate. [Means for solving the problem]

[0007] The inductor component of the present invention comprises a base body including an insulator, a coil provided inside the base body, and a first external electrode electrically connected to the coil, wherein the base body has a first end face and a second end face opposite each other in the longitudinal direction, a first main face and a second main face opposite each other in the height direction perpendicular to the longitudinal direction, and a first side surface and a second side surface opposite each other in the width direction perpendicular to the longitudinal direction and the height direction, the first end face and the first main face intersect at a first ridge, the second end face and the first main face intersect at a second ridge, and the first external electrode is embedded in the base body such that at least a portion of it is exposed from the base body. The material has a first electrode layer, the first electrode layer is exposed on the first main surface at a position away from the second ridge portion and extending from the first ridge portion toward the second ridge portion, and is not exposed on the second main surface. In a cross section along the length direction and the height direction, in a cross section including the first electrode layer, when a first point corresponding to the first ridge portion, a second point corresponding to the second ridge portion, and a third point corresponding to the tip of the first electrode layer on the second ridge portion side located on the first main surface are defined, the third point is located on the second main surface side of a virtual straight line connecting the first point and the second point. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an inductor component that can suppress the occurrence of cracks caused by residual stress at the interface between the external electrode and the substrate. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic perspective view showing an example of an inductor component of the present invention. [Figure 2] Figure 2 is a schematic cross-sectional view showing an example of a cross-section along the line segment a1-a2 of the inductor component shown in Figure 1. [Figure 3] Figure 3 is a schematic cross-sectional view showing another example of the inductor component of the present invention. [Modes for carrying out the invention]

[0010] The inductor components of the present invention will be described below. However, the present invention is not limited to the configuration described below, and may be modified as appropriate without departing from the spirit of the invention. Furthermore, a combination of several of the preferred configurations described below also constitutes the present invention.

[0011] The drawings shown below are schematic representations, and their dimensions, aspect ratios, and scales may differ from those of the actual product.

[0012] In this specification, unless otherwise specified, terms describing relationships between elements (e.g., "parallel," "perpendicular," etc.) and terms describing the shape of elements mean not only their literal, exact form, but also a range that is substantially equivalent, for example, a range that includes differences of a few percent.

[0013] The inductor component of the present invention comprises a base body including an insulator, a coil provided inside the base body, and a first external electrode electrically connected to the coil, wherein the base body has a first end face and a second end face opposite each other in the longitudinal direction, a first main face and a second main face opposite each other in the height direction perpendicular to the longitudinal direction, and a first side surface and a second side surface opposite each other in the width direction perpendicular to the longitudinal direction and the height direction, the first end face and the first main face intersect at a first ridge, the second end face and the first main face intersect at a second ridge, and the first external electrode is embedded in the base body such that at least a portion of it is exposed from the base body. The material has a first electrode layer, the first electrode layer is exposed on the first main surface at a position away from the second ridge portion and extending from the first ridge portion toward the second ridge portion, and is not exposed on the second main surface. In a cross section along the length direction and the height direction, in a cross section including the first electrode layer, when a first point corresponding to the first ridge portion, a second point corresponding to the second ridge portion, and a third point corresponding to the tip of the first electrode layer on the second ridge portion side located on the first main surface are defined, the third point is located on the second main surface side of a virtual straight line connecting the first point and the second point.

[0014] Figure 1 is a schematic perspective view showing an example of an inductor component of the present invention.

[0015] The inductor component 1A shown in FIG. 1 has a base body 10, a coil 20, and a first external electrode 30a.

[0016] In this specification, the length direction, the height direction, and the width direction are defined as the directions of L, T, and W, respectively, as shown in FIG. 1 and the like. Here, the length direction L, the height direction T, and the width direction W are perpendicular to each other.

[0017] In the example shown in FIG. 1, the width direction W is parallel to the coil axis direction of the coil 20.

[0018] The coil axis direction of the coil 20 is the direction in which the coil axis C of the coil 20 extends.

[0019] The base body 10 has a first end face 11a and a second end face 11b that face each other in the length direction L, a first main face 12a and a second main face 12b that face each other in the height direction T, and a first side face 13a and a second side face 13b that face each other in the width direction W.

[0020] In the example shown in FIG. 1, the first main face 12a extends in the coil axis direction (in FIG. 1, the width direction W).

[0021] In the example shown in FIG. 1, the first main face 12a is a mounting face. Specifically, the first main face 12a is a mounting face that faces a mounting object (for example, a substrate) when the inductor component 1A is mounted. Therefore, in the inductor component 1A, the mounting face corresponding to the first main face 12a extends in the coil axis direction.

[0022] At least one of the surfaces of the base body 10, that is, at least one of the first end face 11a, the second end face 11b, the first main face 12a, the second main face 12b, the first side face 13a, and the second side face 13b may be marked to facilitate identification of each surface.

[0023] The first end face 11a and the second end face 11b do not necessarily intersect strictly orthogonally in the longitudinal direction L. Also, the first main face 12a and the second main face 12b do not necessarily intersect strictly orthogonally in the height direction T. Further, the first side face 13a and the second side face 13b do not necessarily intersect strictly orthogonally in the width direction W.

[0024] The body 10 is, for example, in the shape of a rectangular parallelepiped.

[0025] In this specification, the shape of a rectangular parallelepiped only needs to be a shape that can be said to be substantially rectangular parallelepiped, and includes, for example, a substantially rectangular parallelepiped with rounded corners and edges as described later.

[0026] It is preferable that the body 10 has rounded portions at at least one of the corners and edges.

[0027] The corner of the body 10 is the portion where three faces of the body 10 intersect.

[0028] The edge of the body 10 is the portion where two faces of the body 10 intersect.

[0029] In the example shown in FIG. 1, the first end face 11a and the first main face 12a intersect at the first edge portion 14a. In the example shown in FIG. 1, the second end face 11b and the first main face 12a intersect at the second edge portion 14b. In the example shown in FIG. 1, the first end face 11a and the second main face 12b intersect at the third edge portion 14c. In the example shown in FIG. 1, the second end face 11b and the second main face 12b intersect at the fourth edge portion 14d.

[0030] The body 10 includes an insulator.

[0031] In the example shown in FIG. 1, the insulator is formed by laminating a plurality of insulating layers in the coil axis direction (in FIG. 1, the width direction W).

[0032] In the example shown in FIG. 1, the plurality of insulating layers include an insulating layer 15a, an insulating layer 15b, an insulating layer 15c, and an insulating layer 15d.

[0033] Although not shown in Figure 1, in reality, at least one insulating layer exists between insulating layer 15b and insulating layer 15c in the coil axis direction.

[0034] Note that while Figure 1 shows the boundaries between multiple insulating layers for illustrative purposes, in reality, multiple insulating layers are often integrated, and these boundaries are not clearly visible.

[0035] The insulating materials that constitute the insulator, in this case the insulating materials that constitute the insulating layer, include, for example, glass materials mainly composed of borosilicate glass, ceramic materials, organic materials such as epoxy resins, fluororesins, and polymer resins, and composite materials such as glass epoxy resins. As insulating materials, materials with low dielectric constant and dielectric loss are particularly preferred.

[0036] The insulating materials that make up the multiple insulating layers may be the same as each other, may be different from each other, or may be different in some respects.

[0037] The dimensions of the multiple insulating layers in the coil axis direction may be the same as, different from, or partially different.

[0038] The coil 20 is located inside the base body 10.

[0039] In the example shown in Figure 1, the coil 20 is wound in a spiral shape along the coil axis.

[0040] In the example shown in Figure 1, the coil 20 is formed by electrically connecting multiple coil wires that are stacked in the direction of the coil axis.

[0041] In the example shown in Figure 1, the multiple coil wirings include a first coil wiring 21a and a second coil wiring 21b.

[0042] The first coil wiring 21a is located at the outermost position on the first side surface 13a side in the coil axis direction among the multiple coil wirings.

[0043] The first coil wiring 21a may have a single-layer structure or a multi-layer structure.

[0044] The second coil wiring 21b is located at the outermost position on the second side surface 13b side in the coil axis direction among the multiple coil wirings.

[0045] The second coil wiring 21b may have a single-layer structure or a multi-layer structure.

[0046] Although not shown in Figure 1, in reality, at least one coil wire exists between the first coil wire 21a and the second coil wire 21b in the coil axis direction.

[0047] Examples of conductive materials that make up the coil wiring include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0048] The conductive materials that make up multiple coil wirings may be the same as each other, may be different from each other, or may be different in some parts.

[0049] The dimensions of multiple coil wirings in the coil axis direction may be the same as, different from, or partially different.

[0050] For multiple coil wirings, the dimensions in the direction perpendicular to the direction in which the coil wiring extends, as viewed from the coil axis, that is, the width as viewed from the coil axis, may be the same as each other, may be different from each other, or may be different in some parts.

[0051] Among multiple coil wirings, adjacent coil wirings in the coil axis direction may be electrically connected via a connecting conductor that penetrates the insulating layer between the adjacent coil wirings in the coil axis direction.

[0052] The connecting conductor may have a single-layer structure or a multi-layer structure.

[0053] Examples of conductive materials that make up the connecting conductor include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0054] When viewed from the direction of the coil axis, the coil 20 may have a shape composed of only straight sections, a shape composed of only curved sections, or a shape composed of both straight and curved sections. For example, when viewed from the direction of the coil axis, the coil 20 may have a polygonal shape composed of only straight sections, a circular or elliptical shape composed of only curved sections, or an oval shape (track shape) composed of both straight and curved sections.

[0055] As mentioned above, in the example shown in Figure 1, the coil 20 is constructed with three or more coil wirings, consisting of the first coil wiring 21a and the second coil wiring 21b plus at least one additional coil wiring. However, by adjusting the position of the connecting conductors, it is also possible to construct the coil 20 with only two coil wirings.

[0056] The first external electrode 30a is electrically connected to the coil 20.

[0057] In the example shown in Figure 1, the first external electrode 30a is electrically connected to one end of the coil 20. Specifically, the first external electrode 30a is electrically connected to the first coil wiring 21a, which constitutes the coil 20, via the first lead wiring 22a. In other words, the first lead wiring 22a connects the first coil wiring 21a and the first external electrode 30a.

[0058] The first lead wiring 22a may have a single-layer structure or a multi-layer structure.

[0059] Examples of conductive materials that make up the lead-out wiring include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0060] In this specification, when viewed from the direction of the coil axis, a wire that extends toward the external electrode while being inclined relative to the straight portion of the coil wiring in the path where the coil wiring is electrically connected to the external electrode is defined as a lead wire (for example, the example shown in Figure 1). In this case, when viewed from the direction of the coil axis, the coil wiring and the lead wire are not on the same straight line with respect to the connection point between them. If no wire corresponding to the lead wire as defined above is found when viewed from the direction of the coil axis, a wire that does not overlap the circumference of the coil (extends beyond the circumference of the coil) when viewed from the direction of the coil axis is defined as a lead wire (for example, an example different from Figure 1).

[0061] The first external electrode 30a has a first electrode layer 31a embedded in the base body 10 such that at least a portion of it is exposed from the base body 10.

[0062] The first electrode layer 31a is exposed on the first main surface 12a while extending from the first ridge portion 14a toward the second ridge portion 14b at a position away from the second ridge portion 14b. In other words, the first electrode layer 31a is exposed on a portion of the first main surface 12a.

[0063] In the example shown in Figure 1, the first electrode layer 31a is exposed on a portion of the first main surface 12a on the side of the first ridge 14a. Specifically, the first electrode layer 31a is exposed on the first main surface 12a in a region on the side of the first ridge 14a rather than the center in the length direction L.

[0064] As shown in Figure 1, it is preferable that the first electrode layer 31a further extends from the first main surface 12a to the first end surface 11a via the first ridge portion 14a and is exposed to the first end surface 11a.

[0065] In the example shown in Figure 1, the first electrode layer 31a is exposed from a portion of the first ridge portion 14a on the first main surface 12a to a portion of the first ridge portion 14a on the first end surface 11a.

[0066] Furthermore, the first electrode layer 31a may be exposed only on a portion of the first main surface 12a.

[0067] On the other hand, the first electrode layer 31a is not exposed to the second main surface 12b.

[0068] The dimensions of the first electrode layer 31a in the coil axis direction may be smaller than the dimensions of the first ridge portion 14a in the coil axis direction (the dimensions of the base body 10 in the coil axis direction), or they may be the same as the dimensions of the first ridge portion 14a in the coil axis direction (the dimensions of the base body 10 in the coil axis direction). In other words, the first electrode layer 31a may be in contact with a part of the first ridge portion 14a, or it may be in contact with the entire first ridge portion 14a.

[0069] As shown in Figure 1, it is preferable that the first external electrode 30a further has a second electrode layer 31b provided on the outside of the base body 10 so as to cover the first electrode layer 31a. In other words, it is preferable that the first external electrode 30a has, in order from the coil 20 side, a first electrode layer 31a and a second electrode layer 31b.

[0070] It is preferable that the second electrode layer 31b is in contact with the first electrode layer 31a.

[0071] The second electrode layer 31b is preferably located outside the base body 10, specifically on the first main surface 12a, at a position away from the second ridge portion 14b, and extending toward the second ridge portion 14b. In other words, the second electrode layer 31b is preferably provided on a part of the first main surface 12a.

[0072] In the example shown in Figure 1, the second electrode layer 31b is provided on a portion of the first main surface 12a on the side of the first ridge 14a. Specifically, the second electrode layer 31b is provided on the region of the first main surface 12a that is on the side of the first ridge 14a rather than the center in the length direction L.

[0073] As shown in Figure 1, it is preferable that the second electrode layer 31b further extends from the first main surface 12a to the first end surface 11a via the first ridge portion 14a.

[0074] In the example shown in Figure 1, the second electrode layer 31b extends from a portion of the first ridge portion 14a on the first main surface 12a to a portion of the first ridge portion 14a on the first end surface 11a.

[0075] The second electrode layer 31b may be provided only on a portion of the first main surface 12a.

[0076] On the other hand, it is preferable that the second electrode layer 31b is not provided on the second main surface 12b.

[0077] The dimensions of the second electrode layer 31b in the coil axis direction may be smaller than the dimensions of the first ridge portion 14a in the coil axis direction (the dimensions of the base body 10 in the coil axis direction), or they may be the same as the dimensions of the first ridge portion 14a in the coil axis direction (the dimensions of the base body 10 in the coil axis direction). In other words, the second electrode layer 31b may be in contact with a part of the first ridge portion 14a, or it may be in contact with the entire first ridge portion 14a.

[0078] Examples of conductive materials that constitute the electrode layer include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0079] When the first external electrode 30a has a first electrode layer 31a and a second electrode layer 31b, it is preferable that the first electrode layer 31a is a base electrode layer containing the conductive material described above, and the second electrode layer 31b is a plated electrode layer containing the conductive material described above. In this case, it is preferable that the first external electrode 30a has, in order from the coil 20 side, an Ag base electrode layer as the first electrode layer 31a and a Ni plated electrode layer as the second electrode layer 31b. Furthermore, it is even more preferable that the first external electrode 30a has, in order from the coil 20 side, an Ag base electrode layer as the first electrode layer 31a, a Ni plated electrode layer as the second electrode layer 31b, and a Sn plated electrode layer as another electrode layer covering the second electrode layer 31b.

[0080] Figure 2 is a schematic cross-sectional diagram showing an example of a cross-section along the line segment a1-a2 of the inductor component shown in Figure 1. Specifically, Figure 2 shows a cross-section along the length L and height T of the inductor component 1A shown in Figure 1, including the first coil wiring 21a and the first electrode layer 31a.

[0081] As shown in Figure 2, in a cross-section along the length direction L and the height direction T, in the cross-section including the first electrode layer 31a, we define a first point E1 corresponding to the first ridge portion 14a, a second point E2 corresponding to the second ridge portion 14b, and a third point E3 corresponding to the tip of the first electrode layer 31a on the second ridge portion 14b side located on the first main surface 12a. The third point E3 can also be said to correspond to the intersection of the interface between the first electrode layer 31a and the element 10 (insulator) and the first main surface 12a.

[0082] As shown in Figure 2, when the first point E1, the second point E2, and the third point E3 are defined, the third point E3 is located on the second principal plane 12b side of the virtual line F connecting the first point E1 and the second point E2.

[0083] In conventional inductor components (for example, the multilayer inductor described in Patent Document 1), when the external electrode and the base body (insulator) are formed by a method in which they are fired simultaneously (also called the cofire method), differences in expansion coefficients, elastic moduli, and other properties between the constituent materials of the external electrode and the base body (insulator) can cause residual stress at the interface between the external electrode and the base body (insulator). In conventional inductor components, if residual stress remains at the interface between the external electrode and the base body (insulator), for example, when mounting the inductor component or when flowing the inductor component in equipment such as a special sorting machine, a load (impact) is applied to the inductor component, which can cause cracks to occur inside the inductor component starting from the aforementioned interface. In conventional inductor components, as described above, cracks are more likely to occur starting from the tip of the external electrode located on the main surface (mounting surface) of the base body, at the interface between the external electrode and the base body (insulator) where residual stress can occur.

[0084] In contrast, in the inductor component 1A, the third point E3, which corresponds to the tip of the second ridge portion 14b side of the first electrode layer 31a located on the first main surface 12a, is located on the second main surface 12b side of the interface between the external electrode and the base body 10 (insulator), specifically the interface between the first electrode layer 31a and the base body 10 (insulator). In other words, in the inductor component 1A, the height position of the third point E3 on the first main surface 12a is on the second main surface 12b side of the height positions of the first point E1 and the second point E2. Therefore, when mounting the inductor component 1A, or when flowing the inductor component 1A using equipment such as a special sorting machine, even if the inductor component 1A is placed from the first main surface 12a side, the load applied to the inductor component 1A is less likely to concentrate on the third point E3. Therefore, in the inductor component 1A, even if stress remains at the interface between the first electrode layer 31a and the base body 10 (insulator), cracks caused by that stress are less likely to occur starting from the third point E3 when mounting the inductor component 1A.

[0085] Based on the above, the inductor component 1A makes it possible to realize an inductor component that can suppress the occurrence of cracks caused by residual stress at the interface between the external electrode and the base body 10 (insulator), in this case, at the interface between the first electrode layer 31a and the base body 10 (insulator).

[0086] In the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a, the third point E3 is located on the second main surface 12b side of the virtual line F. In the inductor component 1A, the configuration in which the third point E3 is located on the second main surface 12b side of the virtual line F may be, for example, a cross-section along the length direction L and height direction T that includes the first coil wiring 21a and the first electrode layer 31a (see Figure 2), or a cross-section that includes the second coil wiring 21b and the first electrode layer 31a, or both of these cross-sections, but it is particularly preferable that it is located in any cross-section that includes the first electrode layer 31a.

[0087] In the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a, it is preferable that the entire contour line connecting the first point E1 and the third point E3 on the first main surface 12a is located on the second main surface 12b side with respect to the virtual straight line F, as shown in Figure 2. In other words, in the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a, it is preferable that the entire contour line connecting the first point E1 and the third point E3 on the first main surface 12a does not extend beyond the virtual straight line F to the side opposite to the second main surface 12b, as shown in Figure 2.

[0088] In the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a, as long as the third point E3 is located on the second main surface 12b side of the virtual line F, a portion of the contour line connecting the first point E1 and the third point E3 on the first main surface 12a may be located on the opposite side of the second main surface 12b from the virtual line F. In other words, in the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a, a portion of the contour line connecting the first point E1 and the third point E3 on the first main surface 12a may extend beyond the virtual line F to the side of the second main surface 12b.

[0089] The distance G1 in the height direction T between the third point E3 and the virtual line F is preferably 2 μm or more and 12 μm or less.

[0090] In the example shown in Figure 2, the distance G1 in the height direction T between the third point E3 and the virtual line F corresponds to the dimension of the perpendicular drawn from the third point E3 to the virtual line F.

[0091] When the distance G1 in the height direction T between the third point E3 and the virtual line F is 2 μm or more and 12 μm or less, the occurrence of the aforementioned cracks is sufficiently suppressed, and the decrease in the L value (inductance) and Q value (quality factor) is also sufficiently suppressed.

[0092] If the distance G1 in the height direction T between the third point E3 and the virtual line F is less than 2 μm, the effect of reducing the load on the inductor component 1A from concentrating at the third point E3 may be less likely to be obtained when mounting the inductor component 1A. Therefore, if the distance G1 in the height direction T between the third point E3 and the virtual line F is less than 2 μm, the effect of reducing the likelihood of the aforementioned cracks originating from the third point E3 may be less likely to be obtained.

[0093] If the distance G1 in the height direction T between the third point E3 and the virtual line F is greater than 12 μm, the area in the element 10 where the coil 20 is provided (for example, the distance J1 in the height direction T between the third point E3 and the second main surface 12b) becomes too small, which can cause the inner diameter of the coil 20 to become too small, and thus the L value and Q value may decrease.

[0094] The distance G1 in the height direction T between the third point E3 and the virtual line F is preferably 1% or more and 7% or less of the maximum dimension H of the inductor component 1A in the height direction T.

[0095] If the distance G1 in the height direction T between the third point E3 and the virtual line F is between 1% and 7% of the maximum dimension H of the inductor component 1A in the height direction T, the occurrence of the aforementioned cracks is sufficiently suppressed, and the decrease in L and Q values ​​is also sufficiently suppressed.

[0096] If the distance G1 in the height direction T between the third point E3 and the virtual line F is less than 1% of the maximum dimension H of the inductor component 1A in the height direction T, the effect of reducing the concentration of load on the inductor component 1A at the third point E3 during mounting, etc., may be difficult to obtain. Therefore, if the distance G1 in the height direction T between the third point E3 and the virtual line F is less than 1% of the maximum dimension H of the inductor component 1A in the height direction T, the effect of reducing the likelihood of cracks originating from the third point E3, as described above, may be difficult to obtain.

[0097] If the distance G1 in the height direction T between the third point E3 and the virtual line F is greater than 7% of the maximum dimension H in the height direction T of the inductor component 1A, the area in the element 10 where the coil 20 is provided (for example, the distance J1 in the height direction T between the third point E3 and the second main surface 12b) becomes too small, which can cause the inner diameter of the coil 20 to become too small, and thus the L value and Q value may decrease.

[0098] It is preferable that the distance J1 in the height direction T between the third point E3 and the second main surface 12b is smaller than the distance J2 in the height direction T between the first point E1 and the second main surface 12b.

[0099] In the example shown in Figure 2, the difference between the distance J1 in the height direction T between the third point E3 and the second main surface 12b and the distance J2 in the height direction T between the first point E1 and the second main surface 12b corresponds to the distance G1 in the height direction T between the third point E3 and the virtual line F.

[0100] The shortest distance K1 between the third point E3 and the surface of the coil 20 is preferably 25 μm or less.

[0101] In conventional inductor components, the first electrode layer and the coil are often placed sufficiently far apart to prevent the cracks from reaching the coil and adversely affecting the coil characteristics if the aforementioned cracks occur. Therefore, conventional inductor components have limitations in increasing the inductance value by bringing the first electrode layer and the coil closer together.

[0102] In contrast, in the inductor component 1A, the occurrence of the aforementioned cracks is suppressed, so it is not necessary to place the first electrode layer 31a and the coil 20 at a sufficient distance from each other. Therefore, in the inductor component 1A, the L value can be increased by bringing the first electrode layer 31a and the coil 20 closer together so that the shortest distance K1 between the third point E3 and the surface of the coil 20 is 25 μm or less.

[0103] As shown in Figure 1, it is preferable that the inductor component 1A further has a second external electrode 30b.

[0104] The second external electrode 30b is located at a position away from the first external electrode 30a.

[0105] In the example shown in Figure 1, the second external electrode 30b is positioned perpendicular to the coil axis direction, and in Figure 1, it is located at a distance from the first external electrode 30a in the longitudinal direction L.

[0106] The second external electrode 30b is electrically connected to the coil 20.

[0107] In the example shown in Figure 1, the second external electrode 30b is electrically connected to the other end of the coil 20. Specifically, the second external electrode 30b is electrically connected to the second coil wiring 21b, which constitutes the coil 20, via the second lead wiring 22b. In other words, the second lead wiring 22b connects the second coil wiring 21b and the second external electrode 30b.

[0108] The second lead wiring 22b may have a single-layer structure or a multi-layer structure.

[0109] The conductive material constituting the second lead wiring 22b may be the same as the conductive material constituting the first lead wiring 22a, or it may be different from the conductive material constituting the first lead wiring 22a.

[0110] Preferably, the second external electrode 30b has a third electrode layer 31c embedded in the base body 10 such that at least a portion of it is exposed from the base body 10.

[0111] It is preferable that the third electrode layer 31c is located away from the first electrode layer 31a, extending from the second ridge portion 14b toward the first ridge portion 14a, and exposed on the first main surface 12a. In other words, it is preferable that the third electrode layer 31c is located away from the first electrode layer 31a and exposed on a part of the first main surface 12a.

[0112] In the example shown in Figure 1, the third electrode layer 31c is exposed on a portion of the first main surface 12a on the side of the second ridge 14b. Specifically, the third electrode layer 31c is exposed on the first main surface 12a in a region on the side of the second ridge 14b rather than the center in the length direction L.

[0113] As shown in Figure 1, it is preferable that the third electrode layer 31c further extends from the first main surface 12a to the second end surface 11b via the second ridge portion 14b and is exposed on the second end surface 11b.

[0114] In the example shown in Figure 1, the third electrode layer 31c is exposed from a portion of the second ridge portion 14b side of the first main surface 12a to a portion of the second ridge portion 14b side of the second end surface 11b.

[0115] Furthermore, the third electrode layer 31c may be located at a position away from the first electrode layer 31a and exposed only to a portion of the first main surface 12a.

[0116] On the other hand, the third electrode layer 31c is not exposed to the second main surface 12b.

[0117] The dimensions of the third electrode layer 31c in the coil axis direction may be smaller than the dimensions of the second ridge portion 14b in the coil axis direction (the dimensions of the base body 10 in the coil axis direction), or they may be the same as the dimensions of the second ridge portion 14b in the coil axis direction (the dimensions of the base body 10 in the coil axis direction). In other words, the third electrode layer 31c may be in contact with a part of the second ridge portion 14b, or it may be in contact with the entire second ridge portion 14b.

[0118] As shown in Figure 1, it is preferable that the second external electrode 30b further has a fourth electrode layer 31d provided on the outside of the base body 10 so as to cover the third electrode layer 31c. In other words, it is preferable that the second external electrode 30b has, in order from the coil 20 side, a third electrode layer 31c and a fourth electrode layer 31d.

[0119] It is preferable that the fourth electrode layer 31d is in contact with the third electrode layer 31c.

[0120] The fourth electrode layer 31d is preferably located outside the base body 10, specifically on the first main surface 12a, at a position away from the first ridge portion 14a, and extending from the second ridge portion 14b toward the first ridge portion 14a. In other words, the fourth electrode layer 31d is preferably provided on a part of the first main surface 12a.

[0121] When the first external electrode 30a has a second electrode layer 31b, it is preferable that the fourth electrode layer 31d extends from the second ridge portion 14b toward the first ridge portion 14a at a position away from the second electrode layer 31b on the outside of the base body 10, specifically on the first main surface 12a. In other words, it is preferable that the fourth electrode layer 31d is provided at a position away from the second electrode layer 31b on a part of the first main surface 12a.

[0122] In the example shown in Figure 1, the fourth electrode layer 31d is provided on a portion of the first main surface 12a on the side of the second ridge 14b. Specifically, the fourth electrode layer 31d is provided on the region of the first main surface 12a that is on the side of the second ridge 14b rather than the center in the length direction L.

[0123] As shown in Figure 1, it is preferable that the fourth electrode layer 31d further extends from the first main surface 12a to the second end surface 11b via the second ridge portion 14b.

[0124] In the example shown in Figure 1, the fourth electrode layer 31d extends from a portion of the second ridge portion 14b on the first main surface 12a to a portion of the second ridge portion 14b on the second end surface 11b.

[0125] The fourth electrode layer 31d may be provided only on a portion of the first main surface 12a. If the first external electrode 30a has a second electrode layer 31b, the fourth electrode layer 31d may be provided at a position away from the second electrode layer 31b, and only on a portion of the first main surface 12a.

[0126] On the other hand, it is preferable that the fourth electrode layer 31d is not provided on the second main surface 12b.

[0127] The dimensions of the fourth electrode layer 31d in the coil axis direction may be smaller than the dimensions of the second ridge portion 14b in the coil axis direction (the dimensions of the base body 10 in the coil axis direction), or they may be the same as the dimensions of the second ridge portion 14b in the coil axis direction (the dimensions of the base body 10 in the coil axis direction). In other words, the fourth electrode layer 31d may be in contact with a part of the second ridge portion 14b, or it may be in contact with the entire second ridge portion 14b.

[0128] When the second external electrode 30b has a third electrode layer 31c and a fourth electrode layer 31d, it is preferable that the third electrode layer 31c is a base electrode layer containing the conductive material described above, and the fourth electrode layer 31d is a plated electrode layer containing the conductive material described above. In this case, it is preferable that the second external electrode 30b has, in order from the coil 20 side, an Ag base electrode layer as the third electrode layer 31c and a Ni plated electrode layer as the fourth electrode layer 31d. Furthermore, it is even more preferable that the second external electrode 30b has, in order from the coil 20 side, an Ag base electrode layer as the third electrode layer 31c, a Ni plated electrode layer as the fourth electrode layer 31d, and a Sn plated electrode layer as another electrode layer covering the fourth electrode layer 31d.

[0129] In the cross-section shown in Figure 2, in addition to the first point E1, the second point E2, and the third point E3, a fourth point E4 is defined, which corresponds to the tip of the third electrode layer 31c on the first ridge portion 14a side, located on the first main surface 12a. The fourth point E4 can also be said to correspond to the intersection of the interface between the third electrode layer 31c and the base material 10 (insulator) and the first main surface 12a.

[0130] As shown in Figure 2, when the first point E1, second point E2, third point E3, and fourth point E4 are defined, it is preferable that the fourth point E4 is located on the second principal surface 12b side of the virtual line F.

[0131] In the inductor component 1A, if the fourth point E4, which corresponds to the tip of the third electrode layer 31c on the first edge portion 14a side of the interface between the external electrode and the base body 10 (insulator), specifically the interface between the third electrode layer 31c and the base body 10 (insulator), is located on the second main surface 12b side of the virtual line F, then when mounting the inductor component 1A, even if the inductor component 1A is placed from the first main surface 12a side, the load applied to the inductor component 1A will not concentrate at the fourth point E4, similar to the third point E3. Therefore, even if stress remains at the interface between the third electrode layer 31c and the base body 10 (insulator) in the inductor component 1A, cracks caused by that stress are less likely to occur starting from the fourth point E4 when mounting the inductor component 1A.

[0132] In the inductor component 1A, it is preferable that in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a and the third electrode layer 31c, the fourth point E4 is located on the second main surface 12b side of the virtual line F. In the inductor component 1A, the configuration in which the fourth point E4 is located on the second main surface 12b side of the virtual line F may consist of, for example, a cross-section along the length direction L and height direction T that includes the first coil wiring 21a, the first electrode layer 31a, and the third electrode layer 31c (see Figure 2), or a cross-section that includes the second coil wiring 21b, the first electrode layer 31a, and the third electrode layer 31c, or both of these cross-sections, but it is particularly preferable that it consists of any cross-section that includes the first electrode layer 31a and the third electrode layer 31c.

[0133] In the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a and the third electrode layer 31c, it is preferable that the entire contour line connecting the second point E2 and the fourth point E4 on the first main surface 12a is located on the second main surface 12b side with respect to the virtual straight line F, as shown in Figure 2. In other words, in the inductor component 1A, in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a and the third electrode layer 31c, it is preferable that the entire contour line connecting the second point E2 and the fourth point E4 on the first main surface 12a does not extend beyond the virtual straight line F to the side opposite to the second main surface 12b, as shown in Figure 2.

[0134] In the inductor component 1A, if the fourth point E4 is located on the second main surface 12b side of the virtual line F in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a and the third electrode layer 31c, then a portion of the contour line connecting the second point E2 and the fourth point E4 on the first main surface 12a may be located on the opposite side of the second main surface 12b from the virtual line F. In other words, in the inductor component 1A, if the fourth point E4 is located on the opposite side of the virtual line F from the second main surface 12b in any cross-section along the length direction L and height direction T that includes the first electrode layer 31a and the third electrode layer 31c, then a portion of the contour line connecting the second point E2 and the fourth point E4 on the first main surface 12a may extend beyond the virtual line F to the side of the second main surface 12b.

[0135] In the example shown in Figure 2, on the first main surface 12a, the entire contour line connecting the first point E1 and the third point E3, and the entire contour line connecting the second point E2 and the fourth point E4, are located on the second main surface 12b side with respect to the virtual line F, and the first main surface 12a is concave, recessed toward the second main surface 12b side.

[0136] The distance G2 in the height direction T between the fourth point E4 and the virtual line F is preferably 2 μm or more and 12 μm or less.

[0137] In the example shown in Figure 2, the distance G2 in the height direction T between the fourth point E4 and the virtual line F corresponds to the dimension of the perpendicular drawn from the fourth point E4 to the virtual line F.

[0138] When the distance G2 in the height direction T between the fourth point E4 and the virtual line F is 2 μm or more and 12 μm or less, the occurrence of the cracks described above is sufficiently suppressed, and the decrease in the L value and Q value is also sufficiently suppressed.

[0139] If the distance G2 in the height direction T between the fourth point E4 and the virtual line F is less than 2 μm, the effect of reducing the load on the inductor component 1A from concentrating at the fourth point E4 may be difficult to obtain when mounting the inductor component 1A. Therefore, if the distance G2 in the height direction T between the fourth point E4 and the virtual line F is less than 2 μm, the effect of reducing the likelihood of cracks originating from the fourth point E4 may be difficult to obtain.

[0140] If the distance G2 in the height direction T between the fourth point E4 and the virtual line F is greater than 12 μm, the area in the element 10 where the coil 20 is provided (for example, the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b) becomes too small, which can cause the inner diameter of the coil 20 to become too small, and thus the L value and Q value may decrease.

[0141] The distance G2 in the height direction T between the fourth point E4 and the virtual line F is preferably 1% or more and 7% or less of the maximum dimension H of the inductor component 1A in the height direction T.

[0142] If the distance G2 in the height direction T between the fourth point E4 and the virtual line F is between 1% and 7% of the maximum dimension H of the inductor component 1A in the height direction T, the occurrence of the aforementioned cracks is sufficiently suppressed, and the decrease in L value and Q value is also sufficiently suppressed.

[0143] If the distance G2 in the height direction T between the fourth point E4 and the virtual line F is less than 1% of the maximum dimension H of the inductor component 1A in the height direction T, the effect of reducing the concentration of load on the inductor component 1A at the fourth point E4 when mounting the inductor component 1A may be difficult to obtain. Therefore, if the distance G2 in the height direction T between the fourth point E4 and the virtual line F is less than 1% of the maximum dimension H of the inductor component 1A in the height direction T, the effect of reducing the likelihood of cracks originating from the fourth point E4 may be difficult to obtain.

[0144] If the distance G2 in the height direction T between the fourth point E4 and the virtual line F is greater than 7% of the maximum dimension H of the inductor component 1A in the height direction T, the area in the base body 10 where the coil 20 is provided (for example, the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b) becomes too small, which can cause the inner diameter of the coil 20 to become too small, and thus the L value and Q value may decrease.

[0145] It is preferable that the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b is smaller than the distance J4 in the height direction T between the second point E2 and the second main surface 12b.

[0146] In the example shown in Figure 2, the difference between the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b, and the distance J4 in the height direction T between the second point E2 and the second main surface 12b, corresponds to the distance G2 in the height direction T between the fourth point E4 and the virtual line F.

[0147] It is preferable that the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b is the same as the distance J1 in the height direction T between the third point E3 and the second main surface 12b.

[0148] Furthermore, the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b may be different from the distance J1 in the height direction T between the third point E3 and the second main surface 12b. In this case, the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b may be greater than the distance J1 in the height direction T between the third point E3 and the second main surface 12b, or it may be less than the distance J1 in the height direction T between the third point E3 and the second main surface 12b.

[0149] It is preferable that the distance J3 in the height direction T between the fourth point E4 and the second main surface 12b is smaller than the distance J2 in the height direction T between the first point E1 and the second main surface 12b.

[0150] It is preferable that the distance J4 in the height direction T between the second point E2 and the second main surface 12b is greater than the distance J1 in the height direction T between the third point E3 and the second main surface 12b. In other words, it is preferable that the distance J1 in the height direction T between the third point E3 and the second main surface 12b is smaller than the distance J4 in the height direction T between the second point E2 and the second main surface 12b.

[0151] It is preferable that the distance J4 in the height direction T between the second point E2 and the second main surface 12b is the same as the distance J2 in the height direction T between the first point E1 and the second main surface 12b.

[0152] Furthermore, the distance J4 in the height direction T between the second point E2 and the second main surface 12b may be different from the distance J2 in the height direction T between the first point E1 and the second main surface 12b. In this case, the distance J4 in the height direction T between the second point E2 and the second main surface 12b may be greater than the distance J2 in the height direction T between the first point E1 and the second main surface 12b, or it may be less than the distance J2 in the height direction T between the first point E1 and the second main surface 12b.

[0153] The shortest distance K2 between the fourth point E4 and the surface of coil 20 is preferably 25 μm or less.

[0154] In inductor component 1A, the occurrence of the aforementioned cracks is suppressed, so it is not necessary to place the third electrode layer 31c and the coil 20 at a sufficient distance from each other. Therefore, in inductor component 1A, the L value can be increased by bringing the third electrode layer 31c and the coil 20 closer together so that the shortest distance K2 between the fourth point E4 and the surface of the coil 20 is 25 μm or less.

[0155] As shown in Figures 1 and 2, it is preferable that the first main surface 12a has a flat portion 12aa located between the first external electrode 30a and the second external electrode 30b. In other words, the first external electrode 30a and the second external electrode 30b are not provided on the flat portion 12aa of the first main surface 12a. Specifically, the first electrode layer 31a and the third electrode layer 31c are not exposed on the flat portion 12aa of the first main surface 12a, and the second electrode layer 31b and the fourth electrode layer 31d are not provided on the flat portion 12aa of the first main surface 12a.

[0156] As shown in Figures 1 and 2, it is preferable that the second main surface 12b is parallel to the flat portion 12aa of the first main surface 12a. In other words, it is preferable that the second main surface 12b is as flat as the flat portion 12aa of the first main surface 12a.

[0157] The statement that the second main surface 12b is parallel to the flat portion 12aa of the first main surface 12a means that, in a cross-section along the length direction L and height direction T as shown in Figure 2, when the contour line of the second main surface 12b is moved in the height direction T and superimposed on the contour line (preferably a straight line) of the flat portion 12aa of the first main surface 12a, the entire contour line of the second main surface 12b lies within a range of ±1 μm in the height direction T relative to the contour line of the flat portion 12aa of the first main surface 12a.

[0158] In the inductor component 1A, if the second main surface 12b is parallel to the flat portion 12aa of the first main surface 12a, then, for example, when mounting the inductor component 1A, even if the inductor component 1A is picked up (e.g., picked up) by a mounting machine (mounter) from the second main surface 12b side, the load applied to the inductor component 1A is less likely to be locally concentrated on the second main surface 12b, for example, on the third edge portion 14c and the fourth edge portion 14d. Therefore, when mounting the inductor component 1A, the load applied to the inductor component 1A from the mounting machine makes it less likely for the inductor component 1A to chip or crack on the second main surface 12b side.

[0159] In addition, in the inductor component, the second main surface 12b does not have to be parallel to the flat portion 12aa of the first main surface 12a.

[0160] Figure 3 is a schematic cross-sectional view showing another example of the inductor component of the present invention.

[0161] In the inductor component 1B shown in Figure 3, the second main surface 12b is not parallel to the flat portion 12aa of the first main surface 12a.

[0162] In the example shown in Figure 3, the second main surface 12b is concave, recessed toward the first main surface 12a.

[0163] When mounting the inductor component 1B, if the inductor component 1B is picked up by the mounting machine from the second main surface 12b side, the load applied to the inductor component 1B tends to concentrate locally on the third ridge 14c and the fourth ridge 14d relative to the second main surface 12b. Therefore, when mounting the inductor component 1B, compared to mounting the inductor component 1A, the load applied to the inductor component 1B from the mounting machine may cause the inductor component 1B to chip or crack on the second main surface 12b side.

[0164] Based on the above, inductor component 1A suppresses defects such as chipping or cracking of the second main surface 12b side due to the load applied during mounting, compared to inductor component 1B.

[0165] The above examples show an embodiment in which the coil axis direction is parallel to the width direction W, but the coil axis direction may also be parallel to the length direction L or to the height direction T.

[0166] When the coil axis direction is parallel to the length direction L or the width direction W, it is preferable that the flat portion 12aa of the first main surface 12a is parallel to the coil axis direction.

[0167] When the coil axis direction is parallel to the height direction T, it is preferable that the flat portion 12aa of the first main surface 12a is perpendicular to the coil axis direction.

[0168] Inductor component 1A is manufactured, for example, by the following method:

[0169] <Process for creating the mother stack> First, an insulating paste layer is formed by repeatedly applying an insulating paste containing, for example, a glass material mainly composed of borosilicate glass, using screen printing or the like. This insulating paste layer later becomes the insulating layer 15a.

[0170] Next, a photosensitive conductive paste layer is formed on the insulating paste layer by coating, for example, a photosensitive conductive paste mainly composed of Ag, using screen printing or the like. Furthermore, the photosensitive conductive paste layer is irradiated with ultraviolet light or the like via a photomask, and then developed with an alkaline solution or the like to form a coil conductor layer, an outer conductor layer, and a lead conductor layer connected to the coil conductor layer and the outer conductor layer on the insulating paste layer. In this way, the coil conductor layer, lead conductor layer, and outer conductor layer are formed in multiple locations by photolithography. The coil conductor layer formed here will later become the first coil wiring 21a. The lead conductor layer formed here will later become the first lead wiring 22a connecting the first coil wiring 21a and the first external electrode 30a (specifically, the first electrode layer 31a). The outer conductor layer formed here will later become a part of the first electrode layer 31a that constitutes the first external electrode 30a, and a part of the third electrode layer 31c that constitutes the second external electrode 30b.

[0171] Furthermore, when forming the coil conductor layer, the lead conductor layer, and the outer conductor layer, instead of exposure using a photomask, for example, DI exposure (also called direct image exposure or direct writing) without a photomask may be performed.

[0172] Next, a new insulating paste layer is formed on an already formed insulating paste layer by, for example, applying a photosensitive insulating paste using screen printing. Furthermore, via holes and openings are formed in the insulating paste layer by irradiating the newly formed insulating paste layer with ultraviolet light or the like through a photomask and then developing it with an alkaline solution or the like. In this way, an insulating paste layer with multiple via holes and openings is formed by photolithography. The insulating paste layer formed here includes an insulating paste layer that will later become insulating layer 15b. The via holes formed here overlap with a portion of the already formed coil conductor layer. The openings formed here overlap with the already formed outer conductor layer.

[0173] Furthermore, when forming an insulating paste layer with via holes and openings, instead of exposure using a photomask, for example, DI exposure without a photomask may be performed.

[0174] Next, a new photosensitive conductive paste layer is formed on top of the already formed insulating paste layer, while simultaneously forming it inside the via holes and openings by coating, for example, a photosensitive conductive paste mainly composed of Ag, using screen printing or the like. Furthermore, by irradiating the photosensitive conductive paste layer with ultraviolet light or the like via a photomask and then developing it with an alkaline solution or the like, a connecting conductor layer is formed inside the via holes, and a new coil conductor layer connected to the connecting conductor layer is formed on top of the insulating paste layer. Furthermore, a new outer conductor layer connected to the already formed outer conductor layer is formed inside the openings, and yet another new outer conductor layer is formed on top of this outer conductor layer. In this way, the coil conductor layer, the connecting conductor layer, and the outer conductor layer are formed by photolithography. The connecting conductor layer formed here will later become a connecting conductor that connects adjacent coil wiring in the coil axis direction.

[0175] Furthermore, when forming the coil conductor layer, connecting conductor layer, and outer conductor layer, instead of exposure using a photomask, for example, DI exposure without a photomask may be performed.

[0176] Subsequently, by repeating the above process, the insulating paste layer, coil conductor layer, connecting conductor layer, and outer conductor layer are formed to form a predetermined laminated structure. For example, the coil conductor layer formed here includes a coil conductor layer that will later become the second coil wiring 21b.

[0177] Furthermore, when forming the coil conductor layer, which will later become the second coil wiring 21b, and the outer conductor layer of the same layer as the coil conductor layer, a lead conductor layer connected to the coil conductor layer and the outer conductor layer is also formed. The lead conductor layer formed here will later become the second lead wiring 22b, which connects the second coil wiring 21b and the second outer electrode 30b (specifically, the third electrode layer 31c).

[0178] Finally, a new insulating paste layer is formed by repeatedly applying an insulating paste containing, for example, a glass material mainly composed of borosilicate glass, using screen printing or the like. The insulating paste layer formed here includes insulating paste layers that will later become insulating layer 15c and insulating layer 15d.

[0179] Based on the above, the motherboard is fabricated.

[0180] The method for forming the conductor patterns of the coil conductor layer, lead conductor layer, connecting conductor layer, and outer conductor layer is not limited to the photolithography method described above. For example, it may be a method of printing and layering conductive paste using a screen printing plate provided with openings in the shape of the conductor pattern, or a method of forming a conductor film by sputtering, vapor deposition, or foil bonding, and then etching the conductor film to form the shape of the conductor pattern, or a method of forming a negative pattern by a semi-additive method, then forming a plating film, and then removing unnecessary parts of the plating film by etching or the like to form the shape of the conductor pattern.

[0181] When forming the conductor patterns of the coil conductor layer, lead conductor layer, connecting conductor layer, and outer conductor layer, a high aspect ratio can be achieved by forming the conductor patterns in multiple stages, thereby reducing losses due to resistance at high frequencies. The method for forming the conductor patterns in multiple stages is not particularly limited. For example, it may be a method of repeatedly layering conductor patterns by repeating the process using the photolithography method as described above, or a method of repeatedly layering conductor patterns formed by the semi-additive method, or a method of layering conductor patterns formed by the semi-additive method and conductor patterns formed by etching a separately plated film in any order, or a method of further plating and growing a plated film formed by the semi-additive method.

[0182] The conductive material constituting the conductor patterns of the coil conductor layer, lead conductor layer, connecting conductor layer, and outer conductor layer is not limited to a photosensitive conductive paste mainly composed of metal, such as the Ag-based photosensitive conductive paste described above, but may also be a conductor containing metals such as Ag, Au, or Cu formed by methods such as sputtering, vapor deposition, foil bonding, or plating.

[0183] The method for forming the insulating paste layer is not limited to the photolithography method described above, but may also be, for example, a method of pressing a sheet made of insulating material, a method of spin-coating the insulating material, or a method of spray-coating the insulating material.

[0184] The method for forming an insulating paste layer with via holes and openings is not limited to the photolithography method described above. For example, an insulating film may be formed by methods such as pressing a sheet made of insulating material, spin-coating an insulating material, or spray-coating an insulating material, and then providing via holes and openings to the insulating film by laser processing, drilling, or the like.

[0185] The insulating material constituting the insulating paste layer is not limited to the glass material mainly composed of borosilicate glass as described above, but may also be, for example, ceramic materials, organic materials such as epoxy resins, fluororesins, and polymer resins, or composite materials such as glass epoxy resins. As the insulating material, materials with low dielectric constant and dielectric loss are particularly preferred.

[0186] <Process for forming the base body, coil, and external electrodes> First, the mother laminate is cut into multiple unfired laminates by dicing or other methods.

[0187] The unfired laminate has an insulating paste laminate section in which insulating paste layers are laminated, a coil conductor laminate section in which coil conductor layers are laminated so that adjacent coil conductor layers are electrically connected via connecting conductor layers, and an external conductor laminate section in which external conductor layers are laminated.

[0188] When the unfired laminate is separated into individual pieces, the outer conductor laminate is exposed at two locations on the bottom surface of at least the insulating paste laminate included in the cut surface of the unfired laminate. The bottom surface of the insulating paste laminate later becomes the first main surface 12a of the base body 10.

[0189] Next, the laminate is produced by firing the unfired laminate.

[0190] When the unfired laminate is fired, the insulating paste layer becomes an insulating layer, and the insulating paste laminate becomes an insulator included in the base body 10. Furthermore, when the unfired laminate is fired, the coil conductor layer becomes a coil wiring, and the coil conductor laminate becomes a coil 20. In addition, when the unfired laminate is fired, one of the two external conductor laminates becomes the first electrode layer 31a of the first external electrode 30a, and the other becomes the third electrode layer 31c of the second external electrode 30b.

[0191] Next, the resulting laminate may be rounded at the corners and edges of the base body 10 by, for example, barrel polishing.

[0192] Finally, using the first electrode layer 31a and the third electrode layer 31c as Ag underlayer electrode layers, a Ni-plated electrode layer and a Sn-plated electrode layer are sequentially formed on the surface of each Ag underlayer electrode layer by plating. Of the two Ni-plated electrode layers formed here, one becomes the second electrode layer 31b of the first external electrode 30a, and the other becomes the fourth electrode layer 31d of the second external electrode 30b. Of the two Sn-plated electrode layers formed here, one becomes a different electrode layer of the first external electrode 30a from the first electrode layer 31a and the second electrode layer 31b, and the other becomes a different electrode layer of the second external electrode 30b from the third electrode layer 31c and the fourth electrode layer 31d. The thicknesses of the Ni-plated electrode layer and the Sn-plated electrode layer are, for example, 2 μm or more and 10 μm or less, respectively.

[0193] In this way, a first external electrode 30a and a second external electrode 30b are formed, each having an Ag base electrode layer, a Ni plated electrode layer, and a Sn plated electrode layer, respectively, starting from the coil 20 side.

[0194] The method for forming the external electrode is not limited to the method of applying a plating treatment to the external conductor laminate exposed on the cut surface of the unfired laminate (at least the bottom surface of the insulating paste laminate), as described above. For example, the external conductor laminate may be exposed on the cut surface of the unfired laminate (at least the bottom surface of the insulating paste laminate) as described above, and then the exposed portion of the external conductor laminate may be dipped in conductive paste, or a conductive paste film may be formed on the exposed portion of the external conductor laminate by sputtering, and then a plating treatment may be applied.

[0195] Based on the above, inductor component 1A is manufactured.

[0196] In the inductor component 1A, as described above (see Figure 2), the first main surface 12a is concave, recessed toward the second main surface 12b, such that the third point E3 is located on the second main surface 12b side of the virtual line F, and furthermore, the fourth point E4 is also located on the second main surface 12b side of the virtual line F. The method for making the first main surface 12a concave in this way is not particularly limited, and for example, the following method can be used.

[0197] In the first method, in the <step for manufacturing the mother laminate>, a portion of the outer edge of each of the multiple insulating paste layers in the laminated structure is formed into a concave shape, so that in the <step for forming the base body, coil, and external electrode>, the bottom surface of the insulating paste laminate is concave. Subsequently, when the unfired laminate with the concave bottom surface of the insulating paste laminate is fired, the first main surface 12a of the resulting base body 10 becomes concave.

[0198] As a second method, in the process of forming the base body, coil, and external electrodes, the first main surface 12a of the base body 10 is made concave by performing polishing, laser processing, etc. on the laminate after firing.

[0199] Inductor component 1A is manufactured, for example, in 0402 size (0.4mm x 0.2mm x 0.2mm). However, the size of inductor component 1A is not limited to 0402 size (0.4mm x 0.2mm x 0.2mm).

[0200] This specification discloses the following:

[0201] <1> A substrate containing an insulator, A coil is provided inside the above-mentioned base body, The coil is electrically connected to a first external electrode, The above-mentioned body has a first end face and a second end face opposite each other in the longitudinal direction, a first main face and a second main face opposite each other in the height direction perpendicular to the longitudinal direction, and a first side face and a second side face opposite each other in the width direction perpendicular to the longitudinal direction and the height direction, The first end face and the first main face intersect at the first ridge line. The above-mentioned second end face and the above-mentioned first main face intersect at the second ridge line, The first external electrode has a first electrode layer embedded in the substrate such that at least a portion of it is exposed from the substrate. The first electrode layer is exposed on the first main surface at a position away from the second ridge, extending from the first ridge toward the second ridge, and not exposed on the second main surface. In a cross-section along the length and height directions described above, in a cross-section including the first electrode layer, when a first point corresponding to the first ridge, a second point corresponding to the second ridge, and a third point corresponding to the tip of the first electrode layer on the second ridge side located on the first main surface are defined, the third point is located on the second main surface side of the imaginary straight line connecting the first point and the second point, the inductor component.

[0202] <2> The distance in the height direction between the third point mentioned above and the imaginary line mentioned above is between 2 μm and 12 μm. <1> The inductor components listed below.

[0203] <3> The distance in the height direction between the third point and the virtual line is between 1% and 7% of the maximum height dimension of the inductor component. <1> or <2> The inductor components listed below.

[0204] <4> The distance in the height direction between the third point and the second main surface is smaller than the distance in the height direction between the first point and the second main surface. <1> ~ <3> An inductor component listed in any one of the following.

[0205] <5> The shortest distance between the third point mentioned above and the surface of the coil is 25 μm or less. <1> ~ <4> An inductor component listed in any one of the following.

[0206] <6> The first electrode layer further extends from the first main surface to the first end surface via the first ridge portion and is exposed at the first end surface. <1> ~ <5> An inductor component listed in any one of the following.

[0207] <7> The first external electrode further comprises a second electrode layer provided outside the base body so as to cover the first electrode layer. <1> ~ <6> An inductor component listed in any one of the following.

[0208] <8> The device further comprises a second external electrode, which is located at a distance from the first external electrode and is electrically connected to the coil. The above-mentioned second external electrode has a third electrode layer embedded in the above-mentioned body such that at least a portion of it is exposed from the above-mentioned body, The third electrode layer extends from the second ridge towards the first ridge at a position away from the first electrode layer, is exposed on the first main surface, and is not exposed on the second main surface. In the cross-sections along the length and height directions described above, when a fourth point is defined in the cross-section including the first electrode layer and the third electrode layer, which is located on the first main surface, the fourth point is located on the second main surface side of the imaginary straight line. <1> ~ <7> An inductor component listed in any one of the following.

[0209] <9> The distance in the height direction between the fourth point and the imaginary line is between 2 μm and 12 μm. <8> The inductor components listed below.

[0210] <10> The distance in the height direction between the fourth point and the virtual line is between 1% and 7% of the maximum height dimension of the inductor component. <8> or <9> The inductor components listed below.

[0211] <11> The distance in the height direction between the fourth point and the second main surface is smaller than the distance in the height direction between the second point and the second main surface. <8> ~ <10> An inductor component listed in any one of the following.

[0212] <12> The shortest distance between the fourth point mentioned above and the surface of the coil is 25 μm or less. <8> ~ <11> An inductor component listed in any one of the following.

[0213] <13> The above-mentioned third electrode layer further extends from the first main surface to the second end surface via the second ridge portion and is exposed at the second end surface. <8> ~ <12> An inductor component listed in any one of the following.

[0214] <14> The above-mentioned second external electrode further has a fourth electrode layer provided on the outside of the base body so as to cover the above-mentioned third electrode layer. <8> ~ <13> An inductor component listed in any one of the following.

[0215] <15> The first main surface has a flat portion located between the first external electrode and the second external electrode. The second main surface is parallel to the flat portion of the first main surface. <8> ~ <14> An inductor component listed in any one of the following. [Explanation of Symbols]

[0216] 1A, 1B inductor components 10 Base Body 11a First end surface 11b Second end surface 12a First main surface 12aa Flat part of the first main surface 12b Second main surface 13a 1st side 13b Second side 14a First ridge section 14b Second ridge section 14c 3rd ridgeline section 14d 4th ridgeline section 15a, 15b, 15c, 15d insulating layer 20 coils 21a Wiring of the first coil 21b Wiring of the second coil 22a 1st lead out wiring 22b 2nd lead out wiring 30a 1st external electrode 30b 2nd external electrode 31a 1st electrode layer 31b Second electrode layer 31c 3rd electrode layer 31d 4th electrode layer C Coil shaft E1 1st point E2 2nd point E3 3rd point E4 4th point F Virtual Line G1 Distance in the height direction between the third point and the virtual line G2 Distance in the height direction between the fourth point and the virtual line H Maximum dimension in the height direction of the inductor component J1 Distance in the height direction between the third point and the second main plane J2 Distance in the height direction between the first point and the second main plane J3 Distance in the height direction between the fourth point and the second main plane J4 Distance in the height direction between the second point and the second principal plane K1 Shortest distance between the third point and the surface of the coil K2 Shortest distance between point 4 and the surface of the coil L (Length direction) T (height direction) W (width direction)

Claims

1. A substrate containing an insulator, A coil provided inside the aforementioned body, The coil comprises a first external electrode electrically connected to the coil, The body has a first end face and a second end face opposite each other in the longitudinal direction, a first main face and a second main face opposite each other in the height direction perpendicular to the longitudinal direction, and a first side face and a second side face opposite each other in the width direction perpendicular to the longitudinal direction and the height direction. The first end face and the first main face intersect at the first ridge line, The second end face and the first main face intersect at the second ridge line, The first external electrode has a first electrode layer embedded in the substrate such that at least a portion of it is exposed from the substrate. The first electrode layer extends from the first ridge portion toward the second ridge portion at a position away from the second ridge portion, is exposed on the first main surface, and is not exposed on the second main surface. Inductor component, in a cross section along the length direction and the height direction, when a first point corresponding to the first ridge, a second point corresponding to the second ridge, and a third point corresponding to the tip of the first electrode layer on the second ridge side located on the first main surface are defined in the cross section including the first electrode layer, the entire contour line connecting the first point and the third point on the first main surface is located on the second main surface side of the virtual straight line connecting the first point and the second point, except for the first point.

2. The inductor component according to claim 1, wherein the distance in the height direction between the third point and the virtual line is 2 μm or more and 12 μm or less.

3. The inductor component according to claim 1, wherein the distance in the height direction between the third point and the virtual line is 1% or more and 7% or less of the maximum dimension of the inductor component in the height direction.

4. The inductor component according to claim 1, wherein the distance in the height direction between the third point and the second main surface is smaller than the distance in the height direction between the first point and the second main surface.

5. The inductor component according to claim 1, wherein the shortest distance between the third point and the surface of the coil is 25 μm or less.

6. The inductor component according to claim 1, wherein the first electrode layer further extends from the first main surface to the first end surface via the first ridge portion and is exposed to the first end surface.

7. The inductor component according to claim 1, wherein the first external electrode further comprises a second electrode layer provided outside the body so as to cover the first electrode layer.

8. The system further comprises a second external electrode located at a distance from the first external electrode and electrically connected to the coil, The second external electrode has a third electrode layer embedded in the substrate such that at least a portion of it is exposed from the substrate. The third electrode layer extends from the second ridge portion toward the first ridge portion at a position away from the first electrode layer, is exposed on the first main surface, and is not exposed on the second main surface. An inductor component according to any one of claims 1 to 7, wherein, in a cross section along the length direction and the height direction, a fourth point corresponding to the tip of the third electrode layer on the first ridge side located on the first main surface is defined in the cross section including the first electrode layer and the third electrode layer, and the fourth point is located on the second main surface side of the virtual straight line.

9. The inductor component according to claim 8, wherein the distance in the height direction between the fourth point and the virtual line is 2 μm or more and 12 μm or less.

10. The inductor component according to claim 8, wherein the distance in the height direction between the fourth point and the virtual line is 1% or more and 7% or less of the maximum dimension of the inductor component in the height direction.

11. The inductor component according to claim 8, wherein the distance in the height direction between the fourth point and the second main surface is smaller than the distance in the height direction between the second point and the second main surface.

12. The inductor component according to claim 8, wherein the shortest distance between the fourth point and the surface of the coil is 25 μm or less.

13. The inductor component according to claim 8, wherein the third electrode layer further extends from the first main surface to the second end surface via the second ridge portion and is exposed on the second end surface.

14. The inductor component according to claim 8, wherein the second external electrode further comprises a fourth electrode layer provided outside the body so as to cover the third electrode layer.

15. The first main surface has a flat portion located between the first external electrode and the second external electrode, The inductor component according to claim 8, wherein the second main surface is parallel to the flat portion of the first main surface.

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