inductor component

Abstract

This invention provides an inductor component that exhibits superior heat dissipation and easily improves orientation recognition. The inductor component comprises: a blank having a first surface and a second surface located opposite to the first surface; a first orientation recognition layer disposed on the first surface; and a second orientation recognition layer disposed on the second surface. The first orientation recognition layer has a first opening extending through the thickness direction of the first orientation recognition layer. The second orientation recognition layer has a second opening extending through the thickness direction of the second orientation recognition layer. The blank has a first exposed portion in the first surface where a portion of the blank protrudes through the first opening, and a second exposed portion in the second surface where a portion of the blank protrudes through the second opening. The first protrusion of the first exposed portion in the thickness direction of the first orientation recognition layer is smaller than the second protrusion of the second exposed portion in the thickness direction of the second orientation recognition layer.

Description

[0001] This application is a divisional application of application number 202010782973.0, filed on August 6, 2020, entitled "Inductor Component". Technical Field

[0002] This invention relates to inductor components. Background Technology

[0003] Conventionally, an inductor component has been described in Japanese Patent Application Publication No. 2011-14940 (Patent Document 1). This inductor component includes: a blank having a first end face and a second end face located opposite to the first end face, and external electrodes disposed on the first and second end faces. The blank also includes: a first side surface (first face) disposed perpendicular to the first and second end faces, and a second side surface (second face) located opposite to the first side surface; a third side surface disposed perpendicular to the first and second end faces and the first and second side surfaces, and a fourth side surface located opposite to the third side surface. A directional identification layer is disposed on the entire surface of the first and second side surfaces. The color of the directional identification layer is different from the color of the third and fourth side surfaces. In this inductor component, the mounting direction of the inductor component is visually identified based on the color difference.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2011-14940

[0005] However, it is known that the above-mentioned inductor components have the following problems.

[0006] The directional identification layer is disposed on the entire surface of the first and second sides, which are not exposed to the outside of the inductor component. Therefore, for example, heat generated inside the blank during the use of the inductor component is hindered by the directional identification layer located between the blank and the outside of the inductor component, resulting in a problem that the heat is difficult to dissipate efficiently to the outside of the inductor component.

[0007] Furthermore, in order to distinguish the directional recognition layers located on the first and second sides, the difference in brightness of the directional recognition layers is created by changing the amount of additives added. To create this difference in brightness, two directional recognition layers must be formed with materials of different compositions, which requires considerable effort.

[0008] Thus, it is difficult to achieve excellent heat dissipation in inductor components, and it is also difficult to easily improve directional recognition. Summary of the Invention

[0009] Therefore, the object of the present invention is to provide an inductor component that has excellent heat dissipation and easily improves directional recognition.

[0010] To address the aforementioned issues, an inductor component according to one aspect of the present invention comprises: a blank having a first surface and a second surface located opposite to the first surface; a first directional identification layer disposed on the first surface; and a second directional identification layer disposed on the second surface, wherein the first directional identification layer has a first opening extending through in the thickness direction of the first directional identification layer, and the second directional identification layer has a second opening extending through in the thickness direction of the second directional identification layer; the blank has a first exposed portion on the first surface where a portion of the blank is exposed through the first opening, and a second exposed portion on the second surface where a portion of the blank is exposed through the second opening; wherein a first protrusion of the first exposed portion in the thickness direction of the first directional identification layer is less than a second protrusion of the second exposed portion in the thickness direction of the second directional identification layer.

[0011] In this specification, the first prominent quantity includes 0 and negative.

[0012] According to the above method, the blank has a first exposed portion exposed at a first opening on a first surface, and a second exposed portion exposed at a second opening on a second surface. Thus, a portion of the blank is exposed to the outside via the first and second openings, thereby efficiently dissipating heat generated inside, for example, when using an inductor component. Consequently, the inductor component exhibits superior heat dissipation performance.

[0013] Furthermore, the first protrusion of the first exposed portion in the thickness direction of the first directional identification layer is less than the second protrusion of the second exposed portion in the thickness direction of the second directional identification layer. Thus, the blank has first and second exposed portions with different protrusion amounts, making it easy and reliable to visually identify the two directional identification layers. Therefore, it is possible to form two directional identification layers that can visually identify each other even if they are made of materials with the same composition, for example. This easily improves the directional identification capability of inductor components.

[0014] Based on the above, inductor components have excellent heat dissipation and can easily improve orientation recognition.

[0015] An inductor component according to one aspect of the present invention has excellent heat dissipation and can easily improve orientation recognition. Attached Figure Description

[0016] Figure 1 This is a perspective view showing a first embodiment of the inductor component of the present invention.

[0017] Figure 2 This is a cross-sectional view of an inductor component.

[0018] Figure 3 yes Figure 2 Enlarged view of part A.

[0019] Figure 4 This is an enlarged cross-sectional view showing a second embodiment of the inductor component of the present invention.

[0020] Figure 5 This is an enlarged cross-sectional view showing a third embodiment of the inductor component of the present invention.

[0021] Explanation of reference numerals in the attached figures

[0022] 1, 1A, 1B…Inductor components; 10…Blank; 12…First surface of the blank; 13…Second surface of the blank; 14, 14A…First exposed portion; 15…Second exposed portion; 16, 16A…Exposed surface of the first exposed portion; 17…Exposed surface of the second exposed portion; 20…Coil; 30…First external electrode; 40…Second external electrode; 50…First directional identification layer; 51, 51B…First opening; 52…Third surface of the first directional identification layer; 53…Fourth surface of the first directional identification layer; 60…Second directional identification layer; 61…Second opening; 62…Fifth surface of the second directional identification layer; 63…Sixth surface of the second directional identification layer; H1…First protrusion; H2…Second protrusion. Detailed Implementation

[0023] The following detailed description of an inductor component according to one embodiment of the present invention is provided through illustrated embodiments. Furthermore, the accompanying drawings contain partially schematic structures and may not reflect actual dimensions or ratios.

[0024] (First Implementation)

[0025] Figure 1 This is a perspective view showing a first embodiment of the inductor component. (As shown) Figure 1 As shown, the inductor component 1 includes: a blank 10; a first directionality identification layer 50 having a first opening 51 that exposes a portion of the blank 10; and a second directionality identification layer 60 having a second opening 61 that exposes a portion of the blank 10. The inductor component 1 also includes: a spiral coil 20 disposed inside the blank 10; and a first external electrode 30 and a second external electrode 40 disposed in the blank 10 and electrically connected to the coil 20.

[0026] The inductor component 1 (first external electrode 30, second external electrode 40) is electrically connected to wiring on a circuit board (not shown), for example, via solder (not shown). The inductor component 1 is used, for example, as an impedance matching coil (matching coil) in high-frequency circuits, and is used in electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, automotive electronics, and medical / industrial machinery. However, the application of the inductor component 1 is not limited to this; for example, it can also be used in tuning circuits, filtering circuits, or rectifier smoothing circuits.

[0027] The outer surface of the inductor component 1 is composed of a first side surface 3, a second side surface 4 located on the opposite side of the first side surface 3, a first end surface 5 connecting the first side surface 3 and the second side surface 4, a second end surface 6 located on the opposite side of the first end surface 5, a bottom surface 7 connecting the first end surface 5 and the second end surface 6, and a top surface 8 located on the opposite side of the bottom surface 7. Furthermore, as shown in the figure, the X direction is the direction connecting the first end surface 5 and the second end surface 6. The Y direction is the direction connecting the first side surface 3 and the second side surface 4. The Y direction is the same as the thickness direction of the first directional identification layer 50 and the thickness direction of the second directional identification layer 60. The Z direction is the direction connecting the bottom surface 7 and the top surface 8. The X, Y, and Z directions are orthogonal to each other. Furthermore, in the blank 10, for example, the thickness in the X direction is 0.4 mm, the thickness in the Y direction is 0.2 mm, and the thickness in the Z direction is 0.2 mm.

[0028] The blank 10 is formed in a generally rectangular parallelepiped shape. The blank 10 has a first face 12 and a second face 13 located opposite to the first face 12. The blank 10 is, for example, a sintered body or a resin body. For example, if the base material in the insulating layer described later is an inorganic material, and the blank 10 is formed by sintering, the blank 10 is a sintered body. If the blank 10 is a sintered body, a portion of the surface of the blank 10 before sintering is sintered while exposed to the atmosphere, thus obtaining the blank 10. Therefore, gases generated during sintering (more specifically, organic matter contained in the blank 10 before sintering, its decomposition products, and its oxidation products, etc.) are easily released, improving degreasing properties. Furthermore, heat dissipation during sintering is excellent.

[0029] Furthermore, for example, if the base material in the insulating layer described later is resin, the blank 10 is a resin body. In this case, heat dissipation is improved, and in practical use, the temperature rise of the article on which the inductor component is mounted is prevented, thus preventing the deterioration of the article.

[0030] The first external electrode 30 and the second external electrode 40 are, for example, made of conductive materials such as Ag, Cu, Au, and glass particles. The first external electrode 30 is L-shaped and extends across the first end face 5 and the bottom face 7. The second external electrode 40 is L-shaped and extends across the second end face 6 and the bottom face 7. The first external electrode 30 is composed of multiple layers of external electrode conductors stacked in mutual contact. The second external electrode 40 is composed of multiple layers of external electrode conductors stacked in mutual contact.

[0031] The coil 20 is, for example, made of the same conductive material and glass particles as the first external electrode 30 and the second external electrode 40. The coil 20 is wound into a spiral shape along the Y direction. That is, the coil 20 has a winding axis (central axis) along the thickness direction of the first directional identification layer 50. The first end of the coil 20 is connected to the first external electrode 30 via the lead-out electrode 22, and the second end of the coil 20 is connected to the second external electrode 40 via the lead-out electrode 22. Furthermore, although in this embodiment the coil 20, the lead-out electrode 22, the first external electrode 30, and the second external electrode 40 are integrated and there is no clear boundary, it is not limited to this. The coil and the external electrodes may be formed using different types of materials or different types of methods, thereby creating a boundary. In addition, the first external electrode 30, the second external electrode 40, the lead-out electrode 22, and the coil 20 may not contain glass particles. The lead-out electrode 22 may also be made of multiple layers of lead-out electrode conductor layers stacked in mutual contact.

[0032] The coil 20 is generally oblong when viewed from the axial direction, but is not limited to this shape. The shape of the coil 20 can also be, for example, circular, elliptical, rectangular, or other polygonal shapes. The axial direction of the coil 20 refers to the direction parallel to the central axis of the helix on which the coil 20 is wound. In this specification, "parallel" is not limited to a precise parallel relationship, but also includes a substantial parallel relationship, taking into account the range of actual deviations.

[0033] The coil 20 includes coil wiring 21 wound along a plane. Multiple coil wirings 21 are stacked along an axial direction. Adjacent coil wirings 21 in the stacking direction are electrically connected in series via through-hole wiring 26. Thus, multiple coil wirings 21 are electrically connected in series and form a spiral. Specifically, the coil 20 is electrically connected in series and has a structure formed by stacking multiple coil wirings 21 with fewer than one winding, and the coil 20 is spiral-shaped. The coil wiring 21 is composed of a single coil conductor layer. Alternatively, the coil wiring 21 can also be composed of multiple coil conductor layers stacked in mutual contact, which can form a coil wiring 21 with a high aspect ratio and high rectangularity. Furthermore, the coil wiring 21 can also be a spiral shape with more than one winding.

[0034] A first directional identification layer 50 is disposed on the first surface 12 of the blank 10. The first directional identification layer 50 has a first opening 51 extending through the thickness direction of the first directional identification layer 50. A second directional identification layer 60 is disposed on the second surface 13 of the blank 10. The second directional identification layer 60 has a second opening 61 extending through the thickness direction of the second directional identification layer 60. In this way, the blank 10 is exposed to the outside through the first opening 51 and the second opening 61, so the heat generated inside the inductor component 1 during use can be efficiently dissipated to the outside. As a result, the inductor component 1 has excellent heat dissipation performance.

[0035] When viewed from the Y direction, the first opening 51 is quadrilateral in shape. The second opening 61 is also quadrilateral in shape, the same as the first opening 51.

[0036] Furthermore, the shapes of the first opening 51 and the second opening 61 can be shapes other than quadrilaterals. Such shapes include, for example, polygons other than quadrilaterals (more specifically, triangles, pentagons, etc.), circles, and ellipses.

[0037] The first opening 51 and the second opening 61 may also be composed of more than one of the same shape. Alternatively, the first opening 51 and the second opening 61 may also be composed of two or more different types of shapes. For example, the first opening 51 and the second opening 61 may also be composed of two or more quadrilaterals. Furthermore, the first opening 51 and the second opening 61 may also be composed of a combination of two or more shapes, such as polygons (more specifically, triangles, quadrilaterals, and pentagons), circles, and ellipses.

[0038] These shapes can be configured differently. In addition, the shape, configuration, etc. of the second opening 61 are the same as those of the first opening 51, but they can also be different from those of the first opening 51.

[0039] Furthermore, regarding the first opening 51, when the inductor component 1 is viewed from the Y direction, it includes not only the case where the first opening 51 is not connected to the outer edge of the first directional identification layer 50, but also the case where the first opening 51 is connected to the outer edge of the first directional identification layer 50.

[0040] Like the first opening 51, when the inductor component 1 is viewed from the Y direction, the second opening 61 includes both cases where the second opening 61 is not connected to the outer edge of the second directional identification layer 60 and cases where the second opening 61 is connected to the outer edge of the second directional identification layer 60.

[0041] Regarding the shape when it is connected to the outer edge of the aforementioned directional identification layer, and for example, the shape when it is not connected to the outer edge of the aforementioned directional identification layer (more specifically, polygonal, circular, and elliptical shapes, etc.), it is a shape that contacts or overlaps with a portion of the outer edge of the first directional identification layer 50 and the second directional identification layer 60. More specifically, it adopts a shape in which the first opening 51 extends in two directions (X direction) along the length direction, and the two outer edges of the first opening 51 overlap with the outer edge of the first directional identification layer 50 extending in the X direction. That is, it adopts a shape (groove-shaped) in which the first directional identification layer 50 is divided into two by the rectangular first opening 51. In addition, it adopts a shape in which the first opening 51 extends in one direction along the length direction (X direction), and the outer edge of the first opening 51 overlaps with the outer edge of the first directional identification layer 50 extending in the X direction. That is, it adopts a shape in which the first directional identification layer 50 becomes a "コ" shape due to the rectangular first opening 51.

[0042] Figure 2 This is a YZ cross-sectional view of inductor component 1. Figure 3 yes Figure 2 An enlarged view of part A. (See image below.) Figure 2 and Figure 3 As shown, the blank 10 has a first surface 12 and a second surface located on the opposite side of the first surface 12. The blank 10 includes a plurality of insulating layers 11. The plurality of insulating layers 11 are stacked in the Y direction. Furthermore, due to firing and other processes, the interface between two adjacent insulating layers of the blank 10 sometimes becomes unclear.

[0043] The coil wiring 21 is formed by winding on the main surface (XZ plane) of the insulating layer 11, which is orthogonal to the axial direction. The axial direction of the coil 20 is the same as the stacking direction of the insulating layer 11.

[0044] The insulating layer 11 is a layered structure unfolded in the XZ plane orthogonal to the stacking direction in the Y direction. The insulating layer 11 comprises an amorphous base material and crystalline materials. The crystalline materials are insulating fillers, preferably quartz (crystalline quartz). The degree of crystallinity of the quartz is not particularly limited. This reduces the refractive index of the crystalline materials. The base material is an insulating solid. The base material is, for example, an inorganic material such as glass, preferably an amorphous glass such as borosilicate glass with B, Si, O, and K as its main components. In this case, the blank 10 is a sintered body. This results in an insulating layer with sufficient mechanical strength and insulating reliability. In addition to borosilicate glass, the glass can also be, for example, glass containing SiO2, B2O3, K2O, Li2O, CaO, ZnO, Bi2O3, and / or Al2O3, such as SiO2-B2O3-K2O glass, SiO2-B2O3-Li2O-CaO glass, SiO2-B2O3-Li2O-CaO-ZnO glass, or Bi2O3-B2O3-SiO2-Al2O3 glass. These glass components can also be a combination of two or more. Furthermore, the base material in the insulating layer may not be glass; it can be other inorganic materials such as ceramic materials like ferrites, or organic materials such as resins. In this case, amorphous materials are preferred. When the base material in the insulating layer is resin, the preform 10 is a resin body. The resin is, for example, epoxy resin and fluororesin. Furthermore, it can also be a combination of the aforementioned inorganic and organic materials. Furthermore, the insulating layer 11 may also be a structure that does not contain crystals in the insulating layer. Materials with low dielectric constant and dielectric loss are also preferred among them. Additionally, if the base material in the insulating layer contains insulating material, at least one of the first exposed portion 14 and the second exposed portion 15 may contain insulating material.

[0045] The insulating layer 11 may also contain a metallic material. When the insulating layer 11 contains a metallic material, at least one of the first exposed portion 14 and the second exposed portion 15 may contain a metallic material. The metallic material is preferably a magnetic metallic material. If the blank 10 contains a magnetic metallic material, the magnetism of the inductor component 1 is improved.

[0046] A first directional identification layer 50 is disposed on the first surface 12 of the blank 10. The first directional identification layer 50 has a third surface 52 opposite to the first surface 12 of the blank 10 and a fourth surface 53 located on the opposite side of the third surface 52 in the first directional identification layer 50. In addition, a second directional identification layer 60 is disposed on the second surface 13 of the blank 10. The second directional identification layer 60 has a fifth surface 62 opposite to the second surface 13 of the blank 10 and a sixth surface 63 located on the opposite side of the fifth surface 62 in the second directional identification layer 60.

[0047] Specifically, the first directional identification layer 50 and the second directional identification layer 60 are stacked on the outer side of the stacking direction of the insulating layer 11. The first directional identification layer 50 and the second directional identification layer 60 serve as the outermost layers of the inductor component 1 and are disposed in the stacking direction of the insulating layer 11. The first directional identification layer 50 and the second directional identification layer 60 are layered and unfolded on the XZ plane, which is orthogonal to the stacking direction in the Y direction. Compared with the insulating layer 11, the first directional identification layer 50 and the second directional identification layer 60 have visual distinctiveness and can achieve good directional alignment of the inductor component 1.

[0048] The first directional identification layer 50 and the second directional identification layer 60 comprise an amorphous matrix material and crystalline structures within the directional identification layer. The matrix material in the directional identification layer is the same as that in the insulating layer, and is preferably an amorphous glass such as borosilicate glass, primarily composed of B, Si, O, and K. The crystalline structures in the directional identification layer contain at least one crystalline pigment. By adding pigment in this way, the first directional identification layer 50 and the second directional identification layer 60 can be colored, thereby enhancing their visibility (identifiability). The pigment is preferably an oxide containing at least one element selected from Ti, Co, Al, and Zr, such as CoAl2O2 (cobalt blue) or TiO2 (titanium dioxide). This results in the first directional identification layer 50 and the second directional identification layer 60, which possess excellent visual recognizability.

[0049] The first opening 51 and the second opening 61 can be located on opposite sides of the blank 10. Specifically, when viewed from the Y direction, the first opening 51 and the second opening 61 at least overlap, preferably completely overlap. If the first opening 51 and the second opening 61 completely overlap when viewed from the Y direction, external air can pass through the inductor component 1 via the first opening 51 and the second opening 61. As a result, the degreasing properties of the inductor component 1 in the Y direction are further improved. When the first opening 51 and the second opening 61 completely overlap when viewed from the Y direction, it is possible to have a structure in which the first directional identification layer 50 and the second directional identification layer 60 are identical.

[0050] When viewed from the thickness direction of the first directional identification layer 50, the first opening 51 and the second opening 61 are positioned to overlap with the winding shaft. That is, the first opening 51 and the second opening 61 are present on the winding shaft of the coil 20. In this case, since the magnetic flux of the coil passes through the first opening 51 and the second opening 61, the magnetic flux does not pass through the first directional identification layer 50 and the second directional identification layer 60. Therefore, regardless of the material of the first directional identification layer 50 and the second directional identification layer 60, the magnetic flux will not be blocked, suppressing the decrease in the Q value of the inductor component 1.

[0051] The blank 10 has a first exposed portion 14 exposed in the first opening 51 on the first surface 12, and a second exposed portion 15 exposed in the second opening 61 on the second surface 13. The first exposed portion 14 protrudes by a first protrusion H1 in the thickness direction of the first directional identification layer 50, which is smaller than the second exposed portion 15 protrudes by a second protrusion H2 in the thickness direction of the second directional identification layer 60.

[0052] In this specification, "first protrusion amount" H1 refers to the maximum height of the first exposed portion 14 in the vertical direction from the first surface 12. The first protrusion amount H1 is based on the first surface 12 (zero: Figure 3 The dashed line parallel to the Z direction of the first exposed portion 14 is positive from the side of the first surface 12 toward the first opening 51, and negative from the side of the first surface 12 toward the second directional recognition layer 60. Figure 3 In the first exposed portion 14, the shape is such that it has a peak (apex) on the upper side (in the direction of the arrow in the Y direction). The first protrusion H1 extends from the first surface 12 to the peak of the first exposed portion 14. The first protrusion H1 can be adjusted, for example, by applying force to the laminate in the Y direction during the manufacturing method of the inductor component 1 described later. Alternatively, the first protrusion H1 can be adjusted, for example, by embedding the burnt raw materials (more specifically, alumina and resin, etc.) into the first opening 51 during the firing process described later.

[0053] Furthermore, the first protrusion H1 can take a value less than 0. Regarding the first protrusion H1 and the second protrusion H2, the first exposed surface and the second exposed surface are measured using a laser microscope (Keyence "VK-X series", magnification 20x) to calculate them.

[0054] In this specification, the first exposed portion 14 exposed in the first opening 51 of the first surface 12 refers to the portion that can be visually confirmed via the first opening 51 of the first surface 12 when viewed from above in the Y direction towards the first directional identification layer 50 side of the inductor component 1. Therefore, as described above, the first exposed portion 14 may also have a shape with a peak (apex) from the reference upward side (in the direction of the arrow in the Y direction). In this case, the first protrusion amount H1 is greater than 0. Alternatively, the first exposed portion 14 may also have a shape with a peak (apex) from the reference downward side (in the direction opposite to the arrow in the Y direction). In this case, the first protrusion amount H1 is less than 0. Furthermore, the first exposed portion 14 includes an exposed surface 16.

[0055] In this specification, "second protrusion amount" H2 refers to the maximum height of the second exposed portion 15 in the vertical direction from the second surface 13. The second protrusion amount H2 is based on the second surface 13 (zero: Figure 3The dashed line parallel to the Z direction of the second exposed portion 15 is positive from the second surface 13 toward the second opening 61, and negative from the second surface 13 toward the first directional identification layer 50. Figure 3 In this design, the second exposed portion 15 is quadrilateral in shape. The exposed surface 17 of the second exposed portion 15 is the same as the sixth surface 63 of the second directional identification layer 60. That is, the second protrusion H2 has the same thickness as the second directional identification layer 60, and the second side surface 4 of the inductor component 1 has no height difference (same surface). As a method of making the surface the same, for example, it can be achieved by laminating the second directional identification layer 60 to the first directional identification layer 50 in the manufacturing method of the inductor component described later. For example, the second protrusion H2 can be adjusted by embedding the raw materials (more specifically, alumina and resin, etc.) burned off in the firing process described later into the second opening 61.

[0056] Furthermore, the second protrusion H2 can take a value greater than 0. Also, in this specification, "same surface" is not limited to a precisely defined same surface; considering the range of actual deviations, it also includes a substantially identical surface.

[0057] In this specification, the second exposed portion 15 exposed in the second opening 61 on the second surface 13 refers to the portion that can be visually confirmed via the second opening 61 of the second surface 13 when viewed from above in the Y direction towards the second directional identification layer 60 side of the inductor component 1. Therefore, as described above, the second exposed portion 15 may also have a convex shape from the reference upward side (in the direction of the arrow in the Y direction). In this case, the second protrusion amount H2 is greater than 0. Alternatively, the second exposed portion 15 may also have a convex shape from the reference downward side (in the direction opposite to the arrow in the Y direction). In this case, the second protrusion amount H2 is less than 0. Furthermore, the second exposed portion 15 includes an exposed surface 17.

[0058] If the first protrusion H1 is less than the second protrusion H2, the blank 10 has a first exposed portion 14 and a second exposed portion 15 with different protrusion amounts. Therefore, the first directional identification layer 50 and the second directional identification layer 60 can be easily and reliably identified by appearance. Thus, the first directional identification layer 50 and the second directional identification layer 60 can be formed so that even materials of the same composition can be visually identified from each other. Therefore, the directional identification of the inductor component 1 can be easily improved. Thus, the inductor component can be reliably mounted in the appropriate direction, and the desired inductance can be obtained.

[0059] (Manufacturing method of inductor components)

[0060] Next, an example of the manufacturing method of inductor component 1 will be described.

[0061] First, a directional identification layer paste containing pigments and primarily composed of borosilicate glass powder is prepared. The pigment is an oxide containing at least one element selected from Ti, Co, Al, and Zr, such as CoAl2O2 (cobalt blue) or TiO2 (titanium dioxide). Furthermore, an insulating paste containing crystalline materials such as quartz and primarily composed of borosilicate glass powder, and a conductive paste primarily composed of Ag are prepared as fillers. After firing as described later, the directional identification layer paste and the insulating paste become a first directional identification layer 50, a second directional identification layer 60, and an insulating layer 11, respectively. At this time, the insulating layer 11 contains a base material of amorphous borosilicate glass and crystalline materials of filler in the insulating layer. The first directional identification layer 50 and the second directional identification layer 60 contain a base material of amorphous borosilicate glass in the directional identification layer and crystalline materials of pigment in the directional identification layer. The conductive paste becomes a conductive paste layer. The conductive paste layer becomes a coil wiring conductor paste layer, a through-hole wiring conductor paste layer, and an external electrode conductor paste layer depending on the application location. They are then fired, as described later, to become the coil conductor layer, the through-hole wiring conductor layer, and the external electrode conductor layer, respectively. The conductive paste may also include Cu or Au instead of Ag as the main metallic component. Furthermore, in this manufacturing method, since photolithography is used, the directional identification layer paste, the insulating paste, and the conductive paste are photosensitive. In the photolithography process, coating is performed via a photomask, and the formed paste layers (insulating paste layer, directional identification paste layer, and conductive paste layer) are exposed to ultraviolet light or the like, and developed using an alkaline solution or the like. Additionally, as described above, the first directional identification layer and the second directional identification layer can be identified based on the difference between the first protrusion H1 of the first exposed portion 14 and the second protrusion H2 of the second exposed portion 15, thus eliminating the need to prepare two directional identification layer pastes with different pigment concentrations. Therefore, costs and the number of processes can be reduced.

[0062] Next, a necessary amount of directional recognition layer paste is coated onto the carrier film by screen printing to form the bottom layer. This bottom layer is part of the second directional recognition layer 60 (the second directional recognition paste layer). A second opening 61 is formed in the bottom layer by a patterning process based on photolithography.

[0063] Next, a necessary amount of insulating paste is applied to the bottom layer by screen printing to form a portion (insulating paste layer) that serves as insulating layer 11. At this time, the insulating paste enters and fills the second opening 61. This insulating paste layer is the portion located outside the coil wiring 21 and serves as the outer insulating layer.

[0064] Next, a necessary amount of conductive paste is applied to the coated insulating paste by screen printing. Through a patterning process based on photolithography, a coil wiring conductor paste layer (serving as the coil conductor layer), an external electrode conductor paste layer (serving as the external electrode conductor layer), and a lead-out electrode conductor paste layer (serving as the lead-out electrode conductor layer) are formed. At this point, the shortest distance between the outer periphery of the coil wiring conductor paste layer and the outer edge of the insulating paste layer (the outer edge formed in the subsequent cutting process) is smaller than the width of the external electrode conductor paste layer.

[0065] Next, a necessary amount of insulating paste is applied to the conductive paste-coated and patterned insulating paste layer via screen printing. Furthermore, openings and vias are formed on the insulating paste layer through a photolithography-based patterning process.

[0066] Next, a necessary amount of conductive paste is applied to the insulating paste layer with openings and through-holes by screen printing. At this point, by filling the openings and through-holes with conductive paste, a through-hole wiring conductor paste layer and an external electrode conductor paste layer are formed. Furthermore, similarly as described above, a coil wiring conductor paste layer, a lead-out electrode conductor paste layer, and an external electrode conductor paste layer are formed by a patterning process based on photolithography.

[0067] By repeating the above steps, an insulating paste layer, a coil wiring conductor paste layer, a through-hole wiring conductor paste layer, a lead-out electrode conductor paste layer, and an external electrode conductor paste layer are further formed.

[0068] Next, the steps of sequentially applying the necessary amount of insulating paste and directional identification layer paste by screen printing are repeated to form an upper insulating paste layer and a first directional identification paste layer as the top layer. A patterning process based on photolithography is then used to form the first opening 51 on the top layer. During the patterning process, the shape of the portion corresponding to the first exposed portion 14 can be controlled by adjusting the exposure conditions (more specifically, the exposure amount) and development conditions (more specifically, the development time and the type of developer). The upper insulating paste layer is an outer insulating paste layer located outside the coil wiring conductor paste layer. After forming the first opening 51, a force is applied to the laminate from the first directional identification paste layer toward the second directional identification paste layer (along the negative Y direction). As a result, the shape of the portion corresponding to the first exposed portion 14 is such that it has a peak (apex) on the upper side (positive Y direction).

[0069] After the above processes, a master laminate is obtained. Furthermore, the master laminate is formed such that multiple portions of the inductor component 1 are arranged in a matrix. Next, the master laminate is cut into multiple unburned laminates by cutting or the like. In the cutting process of the master laminate, the outer electrode conductor layer is exposed in the laminate through the cut surface formed by cutting.

[0070] Next, the unfired laminate is fired under the specified conditions to obtain a blank 10 having a first directional identification layer 50, a second directional identification layer 60, an insulating layer 11, coil wiring 21, through-hole wiring 26, lead-out electrode 22, and a first external electrode 30 and a second external electrode 40. Since the obtained blank 10 is a sintered body, a portion of the surface of the blank 10 before sintering is sintered with the atmosphere exposed. Therefore, gases generated during sintering (more specifically, organic matter contained in the blank 10 before sintering, its decomposition products, and its oxidation products, etc.) are easily released, improving degreasing properties. Furthermore, it exhibits superior heat dissipation during sintering.

[0071] The blank 10 is further subjected to roller processing, and then Ni plating with a thickness of 2μm to 10μm and Sn plating with a thickness of 2μm to 10μm are formed on the exposed portions of the first external electrode 30 and the second external electrode 40 on the blank 10 by roller electroplating. After the above process, an inductor component 1 with dimensions of 0.4mm × 0.2mm × 0.2mm is obtained.

[0072] Furthermore, for example, if the inductor component 1 is manufactured using the manufacturing method described above, the exposed surface 17 of the second exposed portion 15 becomes the same surface as the sixth surface 63 of the second directional identification layer 60. The reason is as follows: Before sintering, the portion serving as the second directional identification layer 60 is disposed on a carrier film and has a second opening 61. In this state, insulating paste is repeatedly applied to the second directional identification layer 60. Since the bottom surface of the second opening 61 is closed by the carrier film and due to the weight of the multiple insulating pastes, the insulating paste enters the second opening 61, filling it with insulating paste. If sintering is performed in this state, the exposed surface 17 of the second exposed portion 15 becomes the same surface as the sixth surface 63 of the second directional identification layer 60.

[0073] Furthermore, the formation of the directional identification paste layer, insulating paste layer, and conductive paste layer is not limited to patterning based on the aforementioned screen printing and photolithography methods. For example, it can also be a method of repeatedly printing based on a screen with openings and printing based on laser or drilling-processed openings, or a sheet lamination method in which multiple sheets are formed by printing and opening each layer, and then the sheets are pressed together. In addition, regarding the coil wiring 21, lead electrode 22, through-hole wiring 26, and the first external electrode 30 and the second external electrode 40, it can also be a method of forming the conductive film (more specifically, a conductive film including Ag, Cu, or Au) formed by etching through sputtering, vapor deposition, foil pressing, etc., without using conductive paste. It can also be a method like a semi-additive method, in which a negative pattern is formed on the seed layer of the conductor with a resist, and then the conductor is further formed in the opening of the resist layer by electroplating, and then the unnecessary parts of the resist layer and the seed layer are removed. Furthermore, by forming the coil wiring 21 in multiple stages, high cross-sectionalization is achieved, thereby reducing losses due to resistance at high frequencies. More specifically, the process of forming and patterning the conductive paste layer based on the above photolithography method can be repeated, or the pattern of repeatedly overlapping conductor films formed using a semi-additive method can be used, or a process of forming a part of the stack by electroplating growth can be used.

[0074] Furthermore, the materials are not limited to those exemplified above, and known materials can be used. In particular, the first directional identification layer 50, the second directional identification layer 60, and the insulating layer 11 can also be made of magnetic materials.

[0075] Furthermore, the insulating material is not limited to glass as described above, but can also be ceramic materials such as ferrite. Additionally, using organic materials such as epoxy resin and fluororesin as the insulating material allows for the fabrication of a resin-based preform. Moreover, the insulating material can also be a composite material such as glass-epoxy resin. Among these, materials with lower dielectric constants and dielectric losses are preferred.

[0076] Furthermore, the dimensions of the inductor component 1 are not limited to 0.4mm × 0.2mm × 0.2mm; for example, they could be 0.6mm × 0.3mm × 0.3mm or 0.2mm × 0.1mm × 0.1mm. Also, the lengths in the Y and Z directions can be unequal; for example, they could be 0.4mm × 0.2mm × 0.3mm, etc.

[0077] Furthermore, the method for forming the first external electrode 30 and the second external electrode 40 is not limited to the method of exposing the first external electrode 30 and the second external electrode 40 embedded in the blank body 10 by cutting and then performing electroplating processing. Alternatively, the first external electrode 30 and the second external electrode 40 may not be embedded in the blank body 10, but may be formed by impregnation or sputtering of conductive paste after cutting, and then electroplating processing may be performed on them.

[0078] (Second Implementation)

[0079] Figure 4 This is an enlarged cross-sectional view showing a second embodiment of the inductor component. Figure 4 Show Figure 3 The first embodiment shown is a variation thereof. The second embodiment differs from the first embodiment in that the exposed surface 16A of the first exposed portion 14A is the same surface as the third surface 52 of the first directional identification layer 50. This different structure will be described below. Furthermore, in the second embodiment, the same reference numerals as in the first embodiment are used to indicate the same structures as in the first embodiment, and therefore their description is omitted.

[0080] (structure)

[0081] like Figure 4 As shown, in the inductor component 1A of the second embodiment, the exposed surface 16A of the first exposed portion 14A is the same as the third surface 52 of the first directional identification layer 50, and the exposed surface 17 of the second exposed portion 15 is the same as the sixth surface 63 of the second directional identification layer 60. The first protrusion amount H1 is 0.

[0082] The exposed surface 16A of the first exposed portion 14A and the surface of the first directional identification layer 50 that contacts the first surface 12 are the same surface. Specifically, the exposed surface 16A of the first exposed portion 14A and the third surface 52 of the first directional identification layer 50 are the same surface. That is, the first opening 51 is not filled by the blank 10. As a result, compared with an inductor component that does not have an opening in the directional identification layer, the surface area on the surface (first side surface 3) of the inductor component 1A on the side of the first directional identification layer 50 is increased by an amount equivalent to that of the side surface (inner surface) of the first opening 51. Therefore, the heat generated inside the inductor component 1A when it is used can be efficiently released to the outside of the inductor component 1A. As a result, the heat dissipation performance of the inductor component 1A is further improved.

[0083] Furthermore, the exposed surface 17 of the second exposed portion 15 is the same surface as the surface of the second directional identification layer 60. Specifically, the exposed surface 17 of the second exposed portion 15 is the same surface as the sixth surface 63 of the second directional identification layer 60. That is, the second opening 61 is completely filled by the blank 10. In contrast, the surface (first side surface 3) on the side of the first directional identification layer 50 of the inductor component 1A is formed as described above, with a first opening 51 not filled by the blank 10. In this way, the shapes of the first exposed portion 14A and the second exposed portion 15 are significantly different from each other, thus making it easy and reliable to identify the first directional identification layer 50 and the second directional identification layer 60. As a result, the directional identification of the inductor component 1A is more easily improved.

[0084] (Manufacturing method of inductor components)

[0085] For example, by not applying force after the first opening 51 is formed in the above-described manufacturing method of inductor component 1, inductor component 1A can be manufactured.

[0086] Furthermore, regarding the manufacturing method of inductor component 1A, for example, the manufacturing method of inductor component 1 described above also includes a curing step for an outer insulating paste layer. In the curing step of the outer insulating paste layer, after the outer insulating paste layer is formed but before the first directional identification paste layer is formed, the outer insulating paste layer is subjected to a drying treatment or a pre-firing treatment, causing the outer insulating paste layer to be cured to a certain extent. Therefore, even if the first directional identification paste layer is formed on the outer insulating paste layer after the drying treatment or pre-firing treatment, the portion corresponding to the first exposed portion 14A will not have a peak shape in the positive Y direction due to the weight of the first directional identification paste layer. Thus, the exposed surface 16A of the first exposed portion 14A is the same surface as the third surface 52 of the first directional identification layer 50.

[0087] (Third Implementation)

[0088] Figure 5 This is an enlarged cross-sectional view showing a third embodiment of the inductor component. Figure 5 Show Figure 3 The third embodiment is a variation of the first embodiment. The cross-sectional shape of the first opening 51B differs from the second embodiment. This difference will be described below. Furthermore, in the third embodiment, reference numerals identical to those in the first and second embodiments are used for the same structures as in the first and second embodiments, and therefore their descriptions are omitted.

[0089] (structure)

[0090] like Figure 5As shown, in the inductor component 1B of the third embodiment, the inner surface of the first opening 51B is inclined so that the inner diameter of the first opening 51B increases from the third surface 52 of the first directional identification layer 50 toward the fourth surface 53. That is, the first opening 51B has a tapered shape.

[0091] Because the inner surface of the first opening 51B is inclined so that the inner diameter of the first opening 51B increases from the third surface 52 toward the fourth surface 53, the surface area of ​​the surface (first side surface 3) on the first directional identification layer 50 side of the inductor component 1B increases by an amount equivalent to the inclination of the inner surface. Therefore, heat generated inside the inductor component 1B can be easily released to the outside of the inductor component 1B through this inner surface.

[0092] Furthermore, the inner surface of the first opening 51B is inclined so that the inner diameter of the first opening 51B increases from the third surface 52 toward the fourth surface 53. That is, the outer opening of the first opening 51B is larger. As a result, heat released from the inside of the inductor component 1B to the first opening 51B can be easily released to the outside of the inductor component 1B.

[0093] Furthermore, since the inner surface of the first opening 51B is inclined so that the inner diameter of the first opening 51B increases from the third surface 52 toward the fourth surface 53, the heat released from the inner surface is not easily retained in the first opening 51B.

[0094] Therefore, when, for example, inductor component 1B is used, the heat generated inside inductor component 1B can be efficiently dissipated to the outside of inductor component 1B. Furthermore, in this case, if the blank 10 is a sintered body, the degreasing and heat dissipation properties during sintering are improved.

[0095] Furthermore, in the inductor component 1B of the third embodiment, the inner surface of the second opening 61B is inclined so that the inner diameter of the second opening 61B increases from the fifth surface 62 of the second directional identification layer 60 toward the sixth surface 63. That is, the second opening 61B has a tapered shape. In addition, the second protrusion H2 is greater than 0. The second opening 61B is filled by the blank 10.

[0096] Because the inner surface of the second opening 61B is inclined, so that the inner diameter of the second opening 61B increases from the fifth surface 62 toward the sixth surface 63, the area of ​​the inner surface (inclined surface) of the second directionality identification layer 60 of the inductor component 1B increases by an amount equivalent to the inclination of the inner surface. Therefore, the contact area between the second directionality identification layer 60 and the blank 10 increases. Consequently, the adhesion between the blank 10 and the second directionality identification layer 60 is improved, suppressing the peeling of the second directionality identification layer 60 from the blank 10. Thus, in this embodiment, the reduction in directionality is suppressed.

[0097] Furthermore, the second opening 61B has a tapered shape, thus suppressing the peeling of the second directional identification layer 60 from the blank 10 through an anchoring effect. Therefore, in this embodiment, the reduction in directional identification is suppressed.

[0098] Furthermore, the first opening may also have an inner surface that is inclined, so that the inner diameter of the first opening decreases from the third surface 52 toward the fourth surface 53. That is, the first opening may also have an inverted conical shape. Because the first opening has an inverted conical shape, the surface area of ​​the first side of the inductor component increases by an amount equivalent to the inclination of the inner surface, so when using the inductor component, the heat generated inside the inductor component can be more efficiently dissipated to the outside of the inductor component.

[0099] Alternatively, the second opening may have an inclined inner surface, so that the inner diameter of the second opening decreases from the fifth surface 62 toward the sixth surface 63. That is, the second opening may also have an inverted conical shape. Because the second opening has an inverted conical shape, the anchoring effect is further improved, and the peeling of the second directional identification layer is suppressed.

[0100] (Manufacturing method of inductor components)

[0101] In the manufacturing method of inductor component 1B, for example, when the first opening 51B is formed in the first orientation recognition layer 50 using photolithography, the inner surface of the first opening 51B can be tilted by adjusting the exposure amount (exposure intensity). Furthermore, a tapered shape can be achieved with less adjustment of the exposure amount by using a negative resist. An inverted tapered shape can be achieved with less adjustment of the exposure amount by using a positive resist.

[0102] Furthermore, the manufacturing conditions described in the first to third embodiments are merely examples. If the first protrusion H1 is smaller than the second protrusion H2, the manufacturing conditions are not limited.

[0103] This invention is not limited to the first to third embodiments, and can be implemented in various ways without changing the spirit of the invention. Furthermore, the structures shown in the first to third embodiments are examples and are not particularly limited; various modifications can be made without substantially departing from the effects of the invention. For example, the elements described in the first to third embodiments can be appropriately combined. For example, the structure described in the first embodiment and the structure in the third embodiment where the inner surface of the first opening 51B is inclined can be combined.

Claims

1. An inductor component comprising: a core having a first surface and a second surface located on the opposite side of the first surface; a first directionality identification layer provided on the first surface; and a second directionality identification layer provided on the second surface, the first directionality identification layer has a first opening portion passing through in the thickness direction of the first directionality identification layer, the second directionality identification layer has a second opening portion passing through in the thickness direction of the second directionality identification layer, the core has a first exposed portion in which a portion of the core on the first surface is exposed in the first opening portion, and a second exposed portion in which a portion of the core on the second surface is exposed in the second opening portion, a first protruding amount of the first exposed portion protruding in the thickness direction of the first directionality identification layer is smaller than a second protruding amount of the second exposed portion protruding in the thickness direction of the second directionality identification layer, and the first opening portion is connected to the outer edge of the first directionality identification layer.

2. The inductor component according to claim 1, wherein the second opening portion is connected to the outer edge of the second directionality identification layer.

3. The inductor component according to claim 1, wherein the first directionality identification layer has a third surface and a fourth surface, the third surface is located on the opposite side of the first surface of the core, and the fourth surface is located on the opposite side of the third surface, and the fourth surface is rectangular.

4. The inductor component according to claim 1, wherein the second directionality identification layer has a fifth surface and a sixth surface, the fifth surface is located on the opposite side of the second surface of the core, and the sixth surface is located on the opposite side of the fifth surface, and the sixth surface is rectangular.

5. The inductor component according to any one of claims 1 to 4, wherein at least one of the first exposed portion and the second exposed portion contains an insulating material.

6. The inductor component according to any one of claims 1 to 4, wherein at least one of the first exposed portion and the second exposed portion contains a metallic material.

7. The inductor component according to any one of claims 1 to 4, wherein the core is a sintered body.

8. The inductor component according to any one of claims 1 to 4, wherein the core is a resin body.

9. The inductor component according to any one of claims 1 to 4, wherein the exposed surface of the second exposed portion and the surface of the second directionality identification layer are the same surface.

10. The inductor component according to any one of claims 1 to 4, wherein the exposed surface of the first exposed portion and the surface of the first directionality identification layer in contact with the first surface are the same surface. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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