This application claims benefit of priority to Japanese Patent Application No. 2022-173532, filed Oct. 28, 2022, the entire content of which is incorporated herein by reference.
The present disclosure relates to an inductor component.
Japanese Unexamined Patent Application Publication No. 2017-191923 discloses an inductor component that includes a cuboid-like base body and outer electrodes. The base body has multiple coil layers and two reinforcing layers. Each of the coil layers includes an insulating layer, a coil conductor extending on the insulating layer, and conductive vias piercing through the insulating layer. The coil layers are laminated together. Coil conductors of the adjacent coil layers are connected to each other using the conductive vias. The reinforcing layers are laminated, respectively, on one principal surface of the laminated body of the coil layers and on the other principal surface of the laminated body that is positioned oppositely to the one principal surface. The reinforcing layers are made of a material having a rigidity higher than that of the insulating layer.
The inductor component described in Japanese Unexamined Patent Application Publication No. 2017-191923 is mounted on a board with a specific surface of the inductor component facing the board in order to obtain, for example, desired electrical characteristics. However, when the inductor component is packaged in a packing material or when the packaged inductor component is mounted on a board, the electronic component may topple over. In such a case, the inductor component may be mounted on the board with an unintended surface of the inductor component facing the board.
Accordingly, the present disclosure provides an inductor component that includes i) a base body made of an insulator, ii) an inductor wire extending inside the base body, iii) extended electrodes connected to the inductor wire, each one of the extended electrodes having a portion exposed to outside of the base body, and iv) outer electrodes connected to respective ones of the extended electrodes. The base body, the inductor wire, and the extended electrodes form a component body together. The component body has a flat bottom surface and a top surface facing oppositely to the bottom surface. An area of the bottom surface is greater than an area of the top surface. When a first sectional area is defined as an area of a section of the component body that is taken along a plane parallel to the bottom surface at an arbitrary position and when a second sectional area is defined as an area of another section of the component body that is taken along another plane parallel to the bottom surface at a position closer to the bottom surface from the arbitrary position, the second sectional area is equal to or greater than the first sectional area.
With this configuration, the area of the bottom surface is greater than the area of the top surface. Accordingly, the bottom surface has the greater area, and the inductor component is placed on the board with the bottom surface facing downward, which reduces the likelihood of the inductor component toppling over.
The likelihood of the inductor component toppling over is reduced.
An embodiment of an inductor component will be described with reference to the drawings. Note that elements of the inductor component in the drawings may be enlarged or exaggerated to facilitate better understanding. Dimensional relationships between elements may be illustrated differently in the drawings or from the actual elements.
As illustrated in
The component body 20 is shaped like a truncated quadrangular pyramid as illustrated in
As illustrated in
In the following description, a first axis X extends parallel to the long sides of the bottom surface 21B. A second axis Y extends parallel to the short sides of the bottom surface 21B. A third axis Z extends in a direction normal to the bottom surface 21B. Of the directions parallel to the first axis X, a direction in which the first end surface 23A faces is a first positive direction X1 and a direction extending oppositely to the first positive direction X1 is a first negative direction X2. Of the directions parallel to the second axis Y, a direction in which the first principal surface 22A faces is a second positive direction Y1 and a direction extending oppositely to the second positive direction Y1 is a second negative direction Y2. Of the directions parallel to the third axis Z, a direction in which the top surface 21A faces is a third positive direction Z1 and a direction extending oppositely to the third positive direction Z1 is a third negative direction Z2.
The first outer electrode 24A is formed on outer surfaces of the component body 20 so as to cover the first end surface 23A entirely and also to cover portions of the first principal surface 22A, the second principal surface 22B, the top surface 21A, and the bottom surface 21B, the portions being positioned closer to the first end surface 23A. In other words, the first outer electrode 24A is an electrode disposed on five surfaces of the component body 20. The first outer electrode 24A is made of a conductive material, such as silver and copper.
The second outer electrode 24B is formed on outer surfaces of the component body 20 so as to cover the second end surface 23B entirely and also to cover portions of the first principal surface 22A, the second principal surface 22B, the top surface 21A, and the bottom surface 21B, the portions being positioned closer to the second end surface 23B. In other words, the second outer electrode 24B is an electrode disposed on five surfaces of the component body 20. The second outer electrode 24B is made of a conductive material, such as silver and copper.
As illustrated in
The base body 26 is a portion of the component body 20 from which the inductor wire 30, the first extended electrode 25A, and the second extended electrode 25B are excluded. The base body 26 is shaped like a truncated quadrangular pyramid, which reflects the above-described shape of the component body 20. The material of the base body 26 is a mixture of glass, resin, and non-magnetic insulator particles. For example, the non-magnetic insulator particles are made of alumina. Accordingly, the base body 26 is an insulator.
As illustrated in
As illustrated in
The second inductor conductor 31B extends inside the base body 26 in a direction parallel to the bottom surface 21B. The second inductor conductor 31B extends also in a direction parallel to any one of the sides of the bottom surface 21B. The second inductor conductor 31B is positioned away from the first inductor conductor 31A in the third positive direction Z1.
The third inductor conductor 31C extends inside the base body 26 in a direction parallel to the bottom surface 21B. The third inductor conductor 31C extends also in a direction parallel to any one of the sides of the bottom surface 21B. The third inductor conductor 31C is positioned away from the second inductor conductor 31B in the third positive direction Z1.
The fourth inductor conductor 31D extends inside the base body 26 in a direction parallel to the bottom surface 21B. The fourth inductor conductor 31D extends also in a direction parallel to any one of the sides of the bottom surface 21B. The fourth inductor conductor 31D is positioned away from the third inductor conductor 31C in the third positive direction Z1.
The fifth inductor conductor 31E extends inside the base body 26 in a direction parallel to the bottom surface 21B. The fifth inductor conductor 31E extends also in a direction parallel to any one of the sides of the bottom surface 21B. The fifth inductor conductor 31E is positioned away from the fourth inductor conductor 31D in the third positive direction Z1.
The sixth inductor conductor 31F extends inside the base body 26 in a direction parallel to the bottom surface 21B. The sixth inductor conductor 31F extends also in a direction parallel to any one of the sides of the bottom surface 21B. The sixth inductor conductor 31F is positioned away from the fifth inductor conductor 31E in the third positive direction Z1.
The first via conductor 32A extends parallel to the third axis Z. The first via conductor 32A connects one end of the first inductor conductor 31A to one end of the second inductor conductor 31B.
The second via conductor 32B extends parallel to the third axis Z. The second via conductor 32B connects one end of the third inductor conductor 31C to the other end of the second inductor conductor 31B, which is the end opposite to the one end to which the first via conductor 32A is connected.
The third via conductor 32C extends parallel to the third axis Z. The third via conductor 32C connects one end of the fourth inductor conductor 31D to the other end of the third inductor conductor 31C, which is the end opposite to the one end to which the second via conductor 32B is connected. The fourth via conductor 32D extends parallel to the third axis Z. The fourth via conductor 32D connects one end of the fifth inductor conductor 31E to the other end of the fourth inductor conductor 31D, which is the end opposite to the one end to which the third via conductor 32C is connected.
The fifth via conductor 32E extends parallel to the third axis Z. The fifth via conductor 32E connects one end of the sixth inductor conductor 31F to the other end of the fifth inductor conductor 31E, which is the end opposite to the one end to which the fourth via conductor 32D is connected.
Accordingly, the first to sixth inductor conductors 31A to 31F and the first to fifth via conductors 32A to 32E form a single inductor wire 30. When the inductor wire 30 is viewed through the component body 20 in a direction parallel to the third axis Z, the inductor wire 30 appears to be a rectangular frame and the first to sixth inductor conductors 31A to 31F are positioned on this rectangular frame. Note that the inductor wire 30 can be integrally formed of the first to sixth inductor conductors 31A to 31F and the first to fifth via conductors 32A to 32E and does not need to have clear boundaries between these conductors.
The first extended electrode 25A and the second extended electrode 25B are portions of the electroconductive member formed inside the base body 26. The first extended electrode 25A and the second extended electrode 25B do not overlap the rectangular frame of the inductor wire 30 when the inductor wire 30 is viewed through the component body 20 in a direction parallel to the third axis Z.
The first extended electrode 25A extends inside the component body 20. The first extended electrode 25A extends in a direction parallel to the bottom surface 21B. A first end of the first extended electrode 25A is connected to the other end of the first inductor conductor 31A, which is the end opposite to the one end to which the first via conductor 32A is connected. A second end of the first extended electrode 25A, which is the end opposite to the first end, is exposed at an outer surface of the base body 26. The second end of the first extended electrode 25A is connected to the first outer electrode 24A. The first extended electrode 25A is made of a conductive material, such as silver and copper. The material of the first extended electrode 25A is the same as that of the inductor wire 30.
The second extended electrode 25B extends inside the component body 20. The second extended electrode 25B extends in a direction parallel to the bottom surface 21B. A first end of the second extended electrode 25B is connected to the other end of the sixth inductor conductor 31F, which is the end opposite to the one end to which the fifth via conductor 32E is connected. A second end of the second extended electrode 25B, which is the end opposite to the first end, is exposed at an outer surface of the base body 26. The second end of the second extended electrode 25B is connected to the second outer electrode 24B. The second extended electrode 25B is made of a conductive material, such as silver and copper. The material of the second extended electrode 25B is the same as that of the inductor wire 30.
The component body 20 is produced using a so-called sheet lamination method. More specifically, the component body 20 is formed by successively laminating a layer containing the insulator only, and then a layer containing the first inductor conductor 31A, the first extended electrode 25A, and the insulator, and then a layer containing the first via conductor 32A and the insulator, and so forth. Subsequently, the laminated body is baked to produce the component body 20. While the laminated body is baked, the resin contained in the base body 26 is volatilized and the glass is sintered. As a result, the base body 26 contracts slightly compared with that before baking.
As illustrated in
As illustrated in
The bottom-side portion 26B does not contract readily compared with the top-side portion 26A during baking because the bottom-side portion 26B has a higher content of the insulator particles. As a result of this, the dimension LB1 of the first lower base becomes greater than the dimension UB1 of the first upper base, and the dimension LB2 of the second lower base becomes greater than the dimension UB2 of the second upper base.
The middle point of the imaginary line segment LS is referred to as a midpoint MP between the top surface 21A and the bottom surface 21B. As a result of the bottom-side portion 26B having a greater average weight density, the average weight density of a portion of the base body 26 between the midpoint MP and the bottom surface 21B is greater than the average weight density of a portion of the base body 26 between the midpoint MP and the top surface 21A.
Note that the weight density of the base body 26 at an arbitrary point can be obtained by taking a portion of the base body 26 out of the inductor component 10 at this point and by dividing the measured weight of the portion by the measured volume of the portion. The average weight density of the top-side portion 26A can be obtained by averaging results of weight density obtained, for example, at three arbitrary points in the top-side portion 26A using the above method. The same method is employed to obtain the average weight density of the bottom-side portion 26B.
The above embodiment and the modification examples described below can be combined with one another insofar as the combination does not pose a technical contradiction.
The shape of the component body 20 is not limited to the truncated quadrangular pyramid insofar as the second sectional area is equal to or greater than the first sectional area. For example, the surfaces of the truncated quadrangular pyramid can be curved. When a cross section is taken by cutting the component body 20 along a plane extending normal to the bottom surface 21B and parallel to the second axis Y or parallel to the first axis X, the cross section is not necessarily shaped like a trapezoid. In the case of the surfaces of the truncated quadrangular pyramid being curved, the surfaces may be concave surfaces or may be convex surfaces. When the component body 20 is cut along multiple planes parallel to the bottom surface 21B at positions from the top surface 21A toward the bottom surface 21B, the area of the section can increase stepwise instead of increasing gradually. The shapes of the top surface 21A and the bottom surface 21B are not limited to rectangles.
The shapes of the first principal surface 22A, the second principal surface 22B, the first end surface 23A, and the second end surface 23B are not limited to trapezoids. For example, only the first principal surface 22A and the second principal surface 22B may be shaped like trapezoids, while the first end surface 23A and the second end surface 23B may be shaped like rectangles.
The material of the first outer electrode 24A, the second outer electrode 24B, the first extended electrode 25A, and the second extended electrode 25B is not limited to what has been described in the above embodiment. Note that the material of these electrodes is preferably a metal of which the necking temperature is lower than those of the materials of the base body 26.
The first outer electrode 24A and the second outer electrode 24B may be, for example, L-shaped electrodes. In this case, for example, the first outer electrode 24A is a laminated electrode formed so as to extend from the bottom surface 21B to the first end surface 23A.
A nickel layer, a tin layer, or a gold layer can be laminated on the surface of the first outer electrode 24A and on the surface of the second outer electrode 24B. The method of laminating another layer on the surfaces of the first outer electrode 24A and the second outer electrode 24B is not specifically limited here. For example, plating can be used for this purpose.
The material of the first extended electrode 25A and the second extended electrode 25B is not limited to the same material as that of the first to sixth inductor conductors 31A to 31F.
The materials of the base body 26 are not limited to what has been described in the above embodiment. Moreover, a portion of the base body 26 includes an insulator made of materials different from those of other portions. The base body 26 is made of sintered glass containing a crystalline filler that serves as the insulator particles.
The structure of the inductor wire 30 is not limited to what has been described in the above embodiment. Insofar as the inductor wire 30 extends inside the component body 20, the shape, length, width, or the like, of the inductor wire 30 can be changed appropriately in accordance with required characteristics. In the above embodiment, the inductor wire 30 extends spirally around the axis extending parallel to the third axis Z. The inductor wire 30, however, can extend spirally around an axis extending parallel to the first axis X or to the second axis Y
The area of the bottom surface 21B can be less than 1.03 times of the area of the top surface 21A insofar as the area of the bottom surface 21B is greater than the area of the top surface 21A.
The average weight density of the bottom-side portion 26B can be less than 1.1 times of the average weight density of the top-side portion 26A. The average weight density of the bottom-side portion 26B can be equal to the average weight density of the top-side portion 26A. In other words, the density of the base body 26 can be entirely uniform. It is preferable, however, that the average weight density of the portion of the base body 26 between the midpoint MP and the bottom surface 21B be greater than the average weight density of the portion of the base body 26 between the midpoint MP and the top surface 21A, from the viewpoint that the center of gravity of the component body 20 is brought closer to the bottom surface 21B from the midpoint MP.
The average weight density of the bottom-side portion 26B can be greater than 1.5 times of the average weight density of the top-side portion 26A. The content of the insulator particles in the bottom-side portion 26B can be greater than 1.5 times of the content of the insulator particles in the top-side portion 26A.
The material of the top-side portion 26A does not need to be the same as that of the bottom-side portion 26B. Even if the material is different between the top-side portion 26A and the bottom-side portion 26B, it is easier to reduce the likelihood of the inductor component 10 toppling over if the bottom surface 21B has an area larger than that of the top surface 21A.
In the above embodiment, the area of the bottom surface 21B is caused to be greater than the area of the top surface 21A due to the difference in the content of the insulator particles between the bottom-side portion 26B and the top-side portion 26A. However, the method of changing the areas of the bottom surface 21B and the top surface 21A is not limited to this. For example, when the component body 20 is produced using the sheet lamination method, the area of each layer can be made gradually smaller while the lamination proceeds from the bottom surface 21B toward the top surface 21A. Alternatively, when a block containing multiple component bodies 20 is separated into individual ones, the block can be cut in a direction inclined from the vertical direction so as to cause the area of the bottom surface 21B to become greater than the area of the top surface 21A.
The method of manufacturing the component body 20 is not limited to the sheet lamination method. For example, a printing and lamination method can be employed. As a variation of the sheet lamination method, sheets on which the inductor conductors or the extended electrodes are printed are laminated on an insulator sheet, and the laminated sheets are pressure-bonded together to produce the component body 20.
The average weight density of the top-side portion 26A or the bottom-side portion 26B of the base body 26 can be obtained differently if it is difficult to take a portion of the base body 26 out of the inductor component 10. For example, pieces having the same compositions as those of the top-side portion 26A and the bottom-side portion 26B may be prepared, and the weight and the volume of each piece may be measured to obtain the corresponding average weight density. The same method may be employed to obtain the average weight density of a portion of the base body 26 at an arbitrary point.
Technical ideas derived from the above embodiment and modification examples are summarized as follows.
Number | Date | Country | Kind |
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2022-173532 | Oct 2022 | JP | national |