Inductor components

Abstract

This invention provides an inductor component capable of improving SRF (Surface Resonance Frequency). The inductor component comprises a blank and a coil, the coil being disposed within the blank and wound axially, the blank containing a void that exists at least within 10 μm of the coil.

Description

Technical Field

[0001] This invention relates to inductor components. Background Technology

[0002] Conventionally, an inductor component has been described in Japanese Patent Application Publication No. 2014-107513 (Patent Document 1). This inductor component includes a blank and a coil, the coil being disposed within the blank and wound axially. The blank is made of glass or the like.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2014-107513

[0004] However, in existing inductor components, the relative permittivity of the blank is relatively high, which makes it impossible to obtain a high self-resonant frequency (SRF). Summary of the Invention

[0005] Therefore, this disclosure is to provide an inductor component that can improve SRF.

[0006] To address the aforementioned issues, one embodiment of the inductor component disclosed herein includes:

[0007] billet; and

[0008] The coil is disposed within the aforementioned blank body and wound along the axial direction.

[0009] The aforementioned blank contains voids.

[0010] The aforementioned gap exists at least within 10 μm of the aforementioned coil.

[0011] According to the above embodiments, by including voids in the billet, the relative permittivity of the billet is reduced, which can improve the SRF.

[0012] Preferably, in one embodiment of the inductor component,

[0013] The size of the aforementioned axial dimension of the aforementioned gap is greater than 0.1 μm and less than 20 μm.

[0014] Here, the "size of the gap along the axis" is a value measured on a cross-section of the shaft containing the coil.

[0015] According to the above embodiments, the strength of the billet can be ensured and the SRF can be improved.

[0016] Preferably, in one embodiment of the inductor component,

[0017] The size of the aforementioned axial dimension of the aforementioned gap is greater than 0.1 μm and less than 10 μm.

[0018] According to the above embodiments, the strength of the billet can be further improved.

[0019] Preferably, in one embodiment of the inductor component,

[0020] There are multiple such gaps.

[0021] The multiple gaps mentioned above are separated by a distance of more than 0.1 μm from each other.

[0022] According to the above embodiment, since multiple voids are dispersed within the billet, the impact can be mitigated across the entire billet when it is subjected to an impact.

[0023] Preferably, in one embodiment of the inductor component,

[0024] The aforementioned coil has multiple coil wirings wound along a plane orthogonal to the aforementioned axis.

[0025] Multiple coil wirings are arranged along the aforementioned axial direction and are electrically connected to each other.

[0026] The aforementioned gaps exist at least in the region between adjacent coil wirings along the aforementioned axial direction.

[0027] Here, the so-called "region between adjacent coil wirings in the axial direction" refers to the region between adjacent coil wirings, which is the area enclosed by a first surface connecting the inner circumferential surface of one coil wiring to the inner circumferential surface of another coil wiring and a second surface connecting the outer circumferential surface of one coil wiring to the outer circumferential surface of another coil wiring.

[0028] According to the above implementation, since gaps are provided at locations where stray capacitance is easily generated, the SRF can be further improved.

[0029] Preferably, in one embodiment of the inductor component,

[0030] On the cross section of the shaft containing the aforementioned coil, the first area ratio is greater than the second area ratio, wherein the first area ratio is the ratio of the gap area to the blank area in the region between adjacent coil wirings along the aforementioned axial direction in all coil wirings, and the second area ratio is the ratio of the gap area to the blank area in the region closer to the axial side of the coil than the inner circumferential surface of the aforementioned coil.

[0031] According to the above embodiments, since there are relatively more gaps in the locations where stray capacitance is easily generated, and relatively fewer gaps in the locations where the impact on stray capacitance is small, the strength of the billet can be ensured more effectively, and the SRF can be improved.

[0032] Preferably, in one embodiment of the inductor component,

[0033] The aforementioned first area ratio is 5 / 95 or higher and 50 / 50 or lower.

[0034] The second area ratio mentioned above is 0 or more and 1 / 99 or less.

[0035] According to the above embodiments, the strength of the billet can be ensured more effectively, and the SRF can be improved.

[0036] Preferably, in one embodiment of the inductor component,

[0037] It also includes external electrodes, which protrude from the surface of the blank.

[0038] The aforementioned external electrode is electrically connected to the aforementioned coil.

[0039] The aforementioned coil has multiple coil wirings wound along a plane orthogonal to the aforementioned axis.

[0040] Multiple coil wirings are arranged along the aforementioned axial direction and are electrically connected to each other.

[0041] The aforementioned gap exists at least in the region where the coil wiring overlaps with the external electrode when viewed from a direction orthogonal to the surface of the blank on which the external electrode is provided.

[0042] According to the above implementation, since gaps are provided at locations where stray capacitance is easily generated, the SRF can be further improved.

[0043] Preferably, in one embodiment of the inductor component,

[0044] On a cross-section parallel to the axis of the coil and orthogonal to the surface of the blank on which the external electrode is provided, the third area ratio is greater than the second area ratio. The third area ratio is the ratio of the gap area in the region where the coil wiring and the external electrode overlap, viewed from a direction orthogonal to the surface of the blank, to the area of ​​the blank. The second area ratio is the ratio of the gap area in the region closer to the axial side of the coil than the inner circumferential surface of the coil, to the area of ​​the blank.

[0045] According to the above embodiments, since there are relatively more gaps in the locations where stray capacitance is easily generated, and relatively fewer gaps in the locations where the impact on stray capacitance is small, the strength of the billet can be ensured more effectively, and the SRF can be improved.

[0046] Preferably, in one embodiment of the inductor component,

[0047] The third area ratio mentioned above is between 5 / 95 and 50 / 50.

[0048] The second area ratio mentioned above is 0 or more and 1 / 99 or less.

[0049] According to the above embodiments, the strength of the billet can be ensured more effectively, and the SRF can be improved.

[0050] Preferably, in one embodiment of the inductor component,

[0051] The aforementioned gap exists at least in a region on the opposite side of the coil's axis from the outer peripheral surface of the coil.

[0052] According to the above embodiments, when the billet is subjected to impact, the impact can be dispersed and mitigated.

[0053] Preferably, in one embodiment of the inductor component,

[0054] On the cross section of the shaft containing the coil, the fourth area ratio is greater than the second area ratio, wherein the fourth area ratio is the ratio of the void area in the region opposite to the axis of the coil to the blank area, and the second area ratio is the ratio of the void area in the region opposite to the axis of the coil to the blank area.

[0055] According to the above embodiments, the strength of the billet can be ensured, and the impact can be mitigated when the billet is subjected to impact.

[0056] Preferably, in one embodiment of the inductor component,

[0057] The relative permittivity of the above-mentioned blank is above 2.0 and below 8.0.

[0058] According to the above implementation method, SRF can be further improved.

[0059] Preferably, in one embodiment of the inductor component,

[0060] The aforementioned coil is exposed in the aforementioned gap.

[0061] According to the above implementation method, SRF can be further improved.

[0062] An inductor component according to one aspect of this disclosure can improve SRF. Attached Figure Description

[0063] Figure 1 This is a perspective view showing a first embodiment of an inductor component.

[0064] Figure 2 This is an exploded 3D view of the inductor component.

[0065] Figure 3 yes Figure 1 Sectional view III-III.

[0066] Figure 4 yes Figure 3 An enlarged view of region A.

[0067] Figure 5 This is a cross-sectional view showing a second embodiment of the inductor component.

[0068] Figure 6 This is a cross-sectional view showing a third embodiment of the inductor component.

[0069] Explanation of reference numerals in the attached figures

[0070] 1, 1A, 1B…Inductor components; 10…Bulk body; 11…Insulating layer; 13…First side surface; 14…Second side surface; 15…First end face; 16…Second end face; 17…Bottom surface; 18…Top surface; 20…Coil; 21…Coil wiring; 25…Coil conductor layer; 26…Conductive wiring; 30…First external electrode; 40…Second external electrode; R1~R4…Region; S1, S2…Inner peripheral surface of coil wiring; S3…First surface; S4, S5…Outer peripheral surface of coil wiring; S6…Second surface; S7…Inner peripheral surface of coil; S9…Outer peripheral surface of coil; L…Coil shaft; V…Gap. Detailed Implementation

[0071] The following is a detailed description of an inductor component according to one embodiment of the present disclosure, illustrated in the figures. Furthermore, the figures contain some schematic representations and may not reflect actual dimensions or proportions.

[0072] (First Implementation)

[0073] Figure 1 This is a perspective view showing a first embodiment of an inductor component. Figure 2 This is an exploded 3D view of an inductor component. (For example...) Figure 1 and Figure 2 As shown, the inductor component 1 includes: a blank 10, a coil 20 wound into a spiral shape along an axis within 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. Figure 1 In order to make the structure easier to understand, the blank 10 is depicted as transparent, but it can also be semi-transparent or opaque.

[0074] The inductor component 1 is electrically connected to a circuit board (not shown) via wiring through a first external electrode 30 and a second external electrode 40. The inductor component 1 is used, for example, as an impedance matching coil (matching coil) in high-frequency circuits, 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, rectifier smoothing circuits, etc.

[0075] The blank 10 is formed into a generally rectangular parallelepiped. The surface of the blank 10 includes a first end face 15 and a second end face 16 facing each other, a first side face 13 and a second side face 14 facing each other, a bottom surface 17 connecting the first end face 15 and the second end face 16, and the first side face 13 and the second side face 14, and a top surface 18 opposite the bottom surface 17. Furthermore, as shown in the figure, the X direction is orthogonal to the first end face 15 and the second end face 16, the Y direction is orthogonal to the first side face 13 and the second side face 14, and the Z direction is orthogonal to the bottom surface 17 and the top surface 18, and is also orthogonal to both the X and Y directions.

[0076] The blank 10 is constructed by stacking multiple insulating layers 11. The insulating layers 11 are made of materials such as borosilicate glass as the main component, ferrite, or resin. The stacking direction of the insulating layers 11 is parallel (Y direction) to the first end face 15, the second end face 16, and the bottom face 17 of the blank 10. That is, the insulating layers 11 are layered extending in the XZ plane. In this application, "parallel" is not limited to a strict parallel relationship; considering the range of actual deviations, it also includes a substantial parallel relationship. Furthermore, due to firing and other processes, the interfaces between the multiple insulating layers 11 may become unclear.

[0077] The first external electrode 30 and the second external electrode 40 are made of conductive materials such as Ag, Cu, Au, or alloys with these materials as the main components. The first external electrode 30 is L-shaped, formed from the first end face 15 to the bottom face 17. The first external electrode 30 is embedded in the blank 10 so that it is exposed from the first end face 15 and the bottom face 17. The second external electrode 40 is L-shaped, formed from the second end face 16 to the bottom face 17. The second external electrode 40 is embedded in the blank 10 so that it is exposed from the second end face 16 and the bottom face 17.

[0078] The first external electrode 30 and the second external electrode 40 have a structure consisting of multiple first external electrode conductor layers 33 and second external electrode conductor layers 43 stacked and embedded in the blank body 10 (insulating layer 11). The first external electrode conductor layer 33 extends along the first end face 15 and the bottom face 17, and the second external electrode conductor layer 43 extends along the second end face 16 and the bottom face 17. Therefore, since the external electrodes 30 and 40 can be embedded within the blank body 10, miniaturization of the inductor component can be achieved compared to a structure where the external electrodes are externally placed in the blank body 10. Furthermore, since the coil 20 and the external electrodes 30 and 40 can be formed in the same process, deviations in the positional relationship between the coil 20 and the external electrodes 30 and 40 can be reduced, thus reducing deviations in the electrical characteristics of the inductor component 1.

[0079] The coil 20 is made of, for example, the same conductive material as the first external electrode 30 and the second external electrode 40. The coil 20 is wound into a spiral shape along the stacking direction of the insulating layer 11. A first end of the coil 20 is connected to the first external electrode 30, and a second end of the coil 20 is connected to the second external electrode 40. Furthermore, in this embodiment, the coil 20 and the first external electrode 30 and the second external electrode 40 are integrated, and there is no clear boundary. However, this is not a limitation; the coil and the external electrodes may be formed from different types of materials and using different methods, thus creating a boundary.

[0080] Viewed axially, coil 20 is generally rectangular, but not limited to this shape. The shape of coil 20 can also be circular, elliptical, rectangular, or other polygonal. Furthermore, coil 20 is wound axially such that the axial direction is parallel to the bottom surface 17 and intersects the first side surface 13 and the second side surface 14. The axis of coil 20 is aligned with the stacking direction (Y direction) of the insulating layer 11. The axis of coil 20 refers to the central axis of the helical shape of coil 20.

[0081] The coil 20 has a plurality of coil wires 21 stacked along the axial direction and a conductive wire 26 extending along the axial direction and connecting adjacent coil wires 21 in the axial direction. The plurality of coil wires 21 are respectively wound along a plane, arranged in the axial direction, electrically connected in series, and form a helix. The coil wires 21 include a coil conductor layer 25. In addition, the coil wires 21 may also include multiple coil conductor layers 25.

[0082] 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 number of turns of the coil wiring 21 is less than one turn, but it can also be more than one turn. The conductive wiring 26 penetrates the insulating layer 11 in the thickness direction (Y direction). Moreover, adjacent coil wirings 21 in the stacking direction are connected in series via the conductive wiring 26.

[0083] Figure 3 yes Figure 1 Sectional view III-III. Figure 3 It is a cross-section of axis L containing coil 20, and it is a cross-section parallel to the XY plane. For example... Figure 3 As shown, the blank 10 includes a void V. The void V exists at least within 10 μm of the coil 20. Specifically, the void V exists within at least 10 μm of the coil wiring 21 and the conductive wiring 26. The void V preferably exists within 10 μm of each of the coil wiring 21 and the conductive wiring 26.

[0084] exist Figure 3In this design, the cross-sectional shape of the void V is circular, but it can also be elliptical, polygonal, or other shapes. When the cross-sectional shape is elliptical, the void V can extend along the axial direction or in a direction orthogonal to the axial direction. Furthermore, the void V can also be a combination of multiple shapes, such as circular, elliptical, or polygonal. Regarding the method for identifying the void V, when the blank 10 is made of glass, for example, during SEM observation, the portion that appears black when illuminated by ring lighting (from the outer periphery) can be identified as a void.

[0085] The formation of the gap V can be controlled by the manufacturing method of the inductor component 1. For example, refer to... Figure 2 and Figure 3 In the manufacturing method of inductor component 1, when coil wiring 21 (coil conductor layer 25) is laminated on insulating layer 11, a compound that decomposes at a desired firing temperature is added at a predetermined position on the coil wiring 21 (coil conductor layer 25) to create a void V at a desired position within the blank 10. Then, during firing, the compound decomposes, forming the void V at the desired position within the blank 10. Alternatively, the compound can be added at a predetermined position on insulating layer 11 as another method. Furthermore, the manufacturing method is not limited to the above method as long as the void V is formed; other manufacturing methods can also be used.

[0086] According to this embodiment, by providing a void V within the billet 10, the relative permittivity of the billet 10 is reduced, thereby increasing the SRF. Specifically, the SRF(f0) can be calculated using Equations 1 and 2 below.

[0087] [Formula 1]

[0088]

[0089] [Equation 2]

[0090]

[0091] in,

[0092] f0: Self-resonant frequency (Hz)

[0093] L: Inductance (H)

[0094] C: Capacitance (F)

[0095] ε0: Vacuum permittivity (F / m)

[0096] ε r Relative permittivity

[0097] l: Distance between electrodes (m)

[0098] S: Electrode area (m²) 2 )

[0099] The relative permittivity of the void V is approximately 1.0, which is lower than that of materials constituting the preform 10, such as borosilicate glass. Therefore, the relative permittivity of the preform 10 containing the void V is lower than that of existing preforms without the void V. As a result, the capacitance C in Equation 2 above is reduced, thereby improving the SRF.

[0100] Preferably, the axial (Y-direction) size of the gap V is 0.1 μm or more and 20 μm or less. The axial size of the gap V can be measured, for example, on a cross-section containing the coil and parallel to the XY plane. There is no particular limitation on the size of the gap V in the direction orthogonal to the axial direction.

[0101] Based on the above structure, since the axial size of the void V is 0.1 μm or more, the SRF can be further improved. Furthermore, since the axial size of the void V is 20 μm or less, the strength of the blank 10 can be ensured.

[0102] Preferably, the axial size of the gap V is greater than 0.1 μm and less than 10 μm.

[0103] Based on the above structure, since the axial size of the void V is 0.1 μm or more, the SRF can be further improved. Furthermore, since the axial size of the void V is 10 μm or less, the strength of the billet 10 can be reliably ensured.

[0104] Preferably, there are multiple gaps V, which are separated by a distance of more than 0.1 μm from each other.

[0105] According to the above structure, since multiple voids V are dispersed within the billet 10, the impact can be mitigated throughout the entire billet 10 when it is subjected to an impact.

[0106] Preferably, the gap V exists at least in the region between axially adjacent coil wirings 21. This will be explained in detail below. Figure 4 yes Figure 3 A magnified view of region A. (See image below.) Figure 4As shown, the "region between axially adjacent coil wirings 21" refers to the region R1 between adjacent coil wirings 21, enclosed by a first surface S3 connecting the inner circumferential surface S1 of one coil wiring 21 to the inner circumferential surface S2 of another coil wiring 21, and a second surface S6 connecting the outer circumferential surface S4 of one coil wiring 21 to the outer circumferential surface S5 of another coil wiring 21. The inner circumferential surfaces S1 and S2 of the coil wiring 21 refer to the surfaces on the axial L side of the coil wiring 21. In other words, they are the radially inner surfaces of the coil wiring 21. The inner circumferential surfaces S1 and S2 of the coil wiring 21 constitute a part of the inner circumferential surface of the coil 20. The outer circumferential surfaces S4 and S5 of the coil wiring 21 refer to the surfaces on the opposite side of the axial L side of the coil wiring 21. In other words, they are the radially outer surfaces of the coil wiring 21. The outer circumferential surfaces S4 and S5 of the coil wiring 21 constitute a part of the outer circumferential surface of the coil 20.

[0107] Based on the above structure, since a gap V is provided at a location where stray capacitance is easily generated, the SRF can be further improved.

[0108] Preferably, such as Figure 3 As shown, in the cross-section of the shaft containing coil 20, the first area ratio (area of ​​gap V / area of ​​blank) is greater than the second area ratio (area of ​​gap V / area of ​​blank). The first area ratio is the ratio of the area of ​​gap V in region R1 between axially adjacent coil wirings 21 to the area of ​​the blank (excluding gap V). The second area ratio is the ratio of the area of ​​gap V in region R2, which is closer to the axial L side of coil 20 than the inner circumferential surface S7 of coil 20, to the area of ​​the blank (excluding gap V). The aforementioned "cross-section of the shaft containing coil 20" is as follows: Figure 3 As shown in the cross-section, any cross-section that includes the axis of coil 20 and is parallel to the XY plane is acceptable. The "inner circumferential surface S7 of coil 20" mentioned above refers to the surface that connects the inner circumferential surfaces of all coil wiring 21.

[0109] According to the above structure, since there are relatively more gaps V in the locations where stray capacitance is easily generated, and relatively fewer gaps V in the locations where the impact on stray capacitance is small, the strength of the blank 10 can be ensured more effectively, and the SRF can be improved.

[0110] Preferably, the first area ratio is 5 / 95 or more and 50 / 50 or less, and the second area ratio is 0 or more and 1 / 99 or less.

[0111] Based on the above structure, the strength of the preform 10 can be ensured more effectively, and the SRF can be improved.

[0112] Preferably, the relative permittivity of the blank 10 is 2.0 or higher and 8.0 or lower.

[0113] Based on the above structure, the relative permittivity is reduced, which can improve the SRF.

[0114] Preferably, such as Figure 3 As shown in the gap V closest to the second side 14, the coil 20 is exposed in the gap V.

[0115] Based on the above structure, the SRF can be further improved. Furthermore, as... Figure 3 Like the other gaps V shown, gap V may not be in contact with coil 20. According to this structure, even if moisture or gas seeps into gap V from the outside, the influence of moisture or gas on coil 20 can be reduced.

[0116] Preferably, in the cross-section of the shaft containing the coil 20, the area ratio of axial voids with a size of less than 0.1 μm relative to the area of ​​the blank 10 is less than 1.0%.

[0117] Based on the above structure, the strength of the billet 10 can be ensured because the compactness of the billet 10 can be ensured.

[0118] (Second Implementation)

[0119] Figure 5 This is a cross-sectional view showing a second embodiment of the inductor component. Additionally, Figure 5 It is a cross-section that includes the axis L of the coil 20 and intersects with the first external electrode 30; in this embodiment, it is a cross-section parallel to the XY plane. Furthermore, for convenience, Figure 5 Only the portion from the axis L of coil 20 to the side of the first end face 15 is shown. The second embodiment differs from the first embodiment in the location of the gap. This difference in structure will be described below. Other structures are the same as in the first embodiment, and are labeled with the same reference numerals as in the first embodiment, with their descriptions omitted.

[0120] like Figure 5 As shown, the gap V exists at least in the region R3 where the coil wiring 21 overlaps with the first external electrode 30 when viewed from a direction orthogonal to the surface of the blank 10 where the first external electrode 30 is located. In this embodiment, the "surface of the blank 10 where the first external electrode 30 is located" is the first end face 15. Furthermore, since the first external electrode 30 is also embedded in the bottom surface 17, the gap V can also exist in the region R3 where the coil wiring 21 overlaps with the first external electrode 30 when viewed from a direction orthogonal to the bottom surface 17. Additionally, as in this embodiment, when the first external electrode 30 is an L-shaped electrode, the gap V only needs to exist in the region R3 where the coil wiring 21 overlaps with the first external electrode 30 when viewed from a direction orthogonal to at least one of the first end face 15 and the bottom surface 17. The same applies to the second external electrode 40. Furthermore, in Figure 5The diagram shows a cross-section including the axis L of the coil 20, but the cross-section where the gap V exists in this embodiment may not include the axis L of the coil 20. That is, the cross-section where the gap V exists in this embodiment only needs to be a cross-section parallel to the axis L of the coil 20 and orthogonal to the surface of the blank 10 on which the first external electrode 30 is provided and / or the surface of the blank 10 on which the second external electrode 40 is provided, and a cross-section intersecting the coil wiring 21 and the first external electrode 30 and / or the second external electrode 40.

[0121] According to this embodiment, since a gap V is provided at a location where stray capacitance is easily generated, the SRF can be improved.

[0122] Preferably, on a cross-section parallel to the axis L of the coil 20 and orthogonal to the surface of the blank 10 provided with the first external electrode 30 and / or the surface of the blank 10 provided with the second external electrode 40, the third area ratio (area of ​​gap V / area of ​​blank) is greater than the second area ratio. The third area ratio is the ratio of the area of ​​gap V in the region R3 where the coil wiring 21 overlaps with the external electrodes 30 and 40, viewed from a direction orthogonal to the surface of the blank 10, to the area of ​​the blank (excluding gap V). The second area ratio is the ratio of the area of ​​gap V in the region closer to the axis L of the coil than the inner circumferential surface of the coil 20 to the area of ​​the blank.

[0123] Furthermore, the aforementioned "cross-section parallel to the axis L of the coil 20 and orthogonal to the surface of the blank 10 on which the first external electrode 30 is provided and / or the surface of the blank 10 on which the second external electrode 40 is provided" is, for example, as... Figure 5 As shown in the cross-section, any cross-section that includes the axis L of the coil, intersects with the external electrodes 30 and 40, and is parallel to the XY plane is acceptable. If this cross-section does not intersect with the external electrodes 30 and 40, observation can also be performed on a cross-section parallel to the XY plane but intersecting with the external electrodes 30 and 40. Furthermore, in Figure 5 In the cross-section shown, the second area ratio can be calculated using the same method as in the first embodiment.

[0124] According to the above structure, since there are relatively more gaps V in the locations where stray capacitance is easily generated, and relatively fewer gaps V in the locations where the impact on stray capacitance is small, the strength of the blank 10 can be ensured more effectively, and the SRF can be improved.

[0125] Preferably, the third area ratio is 5 / 95 or more and 50 / 50 or less, and the second area ratio is 0 or more and 1 / 99 or less.

[0126] Based on the above structure, the strength of the preform 10 can be ensured more effectively, and the SRF can be improved.

[0127] Preferably, such as Figure 5As shown in the diagram, the gap V does not contact the coil 20 or the external electrodes 30 and 40.

[0128] Based on the above structure, even if moisture or gas seeps into the gap V from the outside, the effects of moisture or gas on the coil 20 and external electrodes 30 and 40 can be reduced. Furthermore, the coil 20 and external electrodes 30 and 40 can also be exposed in the gap V.

[0129] (Third Implementation)

[0130] Figure 6 This is a cross-sectional view showing a third embodiment of the inductor component. Additionally, Figure 6 It is a cross-section that includes the axis L of coil 20 and does not intersect with the first external electrode 30. Furthermore, for convenience, Figure 6 Only the portion from the coil shaft L to the first end face 15 is shown. The third embodiment differs from the first embodiment in the location of the gap. This difference in structure will be described below. Other structures are the same as in the first embodiment, and are labeled with the same reference numerals as in the first embodiment, with their descriptions omitted.

[0131] like Figure 6 As shown, the gap V exists at least in the region R4 opposite to the axis L of coil 20, on the outer peripheral surface S8 of coil 20. The aforementioned "outer peripheral surface S8 of coil 20" refers to the surface formed by connecting the outer peripheral surfaces of all coil wiring 21. Furthermore, in Figure 6 The diagram shows an example in a cross-section containing the axis L of the coil 20 that does not intersect with the first external electrode 30, but it can also be shown as... Figure 5 As shown in the cross-section, in the cross-section that includes the axis L of the coil 20 and intersects with the first external electrode 30, the gap V exists in the region R4, which is on the opposite side of the axis L of the coil 20, relative to the outer peripheral surface S8 of the coil 20.

[0132] According to this embodiment, since there is a gap V in the region on the outer peripheral surface of the coil 20 opposite to the axis L of the coil 20, the impact can be dispersed and mitigated when the blank 10 is impacted.

[0133] Preferably, in the cross-section of the axis L containing the coil 20, the fourth area ratio (area of ​​the gap V / area of ​​the blank) is greater than the second area ratio, wherein the fourth area ratio is the ratio of the area of ​​the gap V in the region R4 on the opposite side of the axis L of the coil 20 from the outer peripheral surface S8 of the coil 20 to the area of ​​the blank (excluding the gap V), and the second area ratio is the ratio of the area of ​​the gap V in the region on the side of the axis L of the coil 20 from the inner peripheral surface of the coil 20 to the area of ​​the blank (excluding the gap V). Figure 6 In the cross-section shown, the second area ratio can be calculated using the same method as in the first embodiment.

[0134] According to the above structure, the strength of the billet 10 can be ensured, and the impact can be mitigated when the billet 10 is subjected to impact.

[0135] Furthermore, this disclosure is not limited to the embodiments described above, and design changes can be made without departing from the spirit of this disclosure. For example, various combinations of the various feature points of the first to third embodiments can be made.

[0136] In the above embodiments, the axis of the coil is orthogonal to the side of the blank, but it can also be orthogonal to the end face of the blank or the bottom face of the blank.

[0137] In the above embodiment, the first external electrode and the second external electrode are L-shaped, but they can also be, for example, five-sided electrodes. That is, the first external electrode can be disposed on the entire surface of the first end face and a portion of each of the first side face, the second side face, the bottom face, and the top face, and the second external electrode can be disposed on the entire surface of the second end face and a portion of each of the first side face, the second side face, the bottom face, and the top face. In this case, as a variation of the second embodiment, a gap exists in the area where the coil wiring overlaps with the external electrode when viewed from a direction orthogonal to at least one of the multiple faces of the blank on which the external electrodes are disposed. Alternatively, the first external electrode and the second external electrode can each be disposed on a portion of the bottom face.

[0138] (Example)

[0139] Hereinafter, an embodiment of the manufacturing method of inductor component 1 will be described.

[0140] First, an insulating paste, primarily composed of borosilicate glass, is repeatedly coated onto a substrate material such as a carrier film using screen printing to form an insulating layer. This insulating layer becomes the outer insulating layer located outside the coil conductor layer. Furthermore, the substrate material is peeled off from the insulating layer in any process, leaving no residue in the inductor component.

[0141] Next, a photosensitive conductive paste layer is coated onto the insulating layer, and a coil conductor layer and an external electrode conductor layer are formed through a photolithography process. Specifically, a photosensitive conductive paste layer with Ag as the main metal component is formed by screen printing onto the insulating layer. Further, the photosensitive conductive paste layer is irradiated with ultraviolet light or the like through a photomask and developed using an alkaline solution or the like. This forms the coil conductor layer and the external electrode conductor layer on the insulating layer. At this point, the coil conductor layer and the external electrode conductor layer can be patterned into a desired pattern using a photomask.

[0142] Then, a photosensitive insulating paste layer is coated onto the insulating layer, and an insulating layer with openings and vias is formed through a photolithography process. Specifically, the photosensitive insulating paste layer is formed by screen printing the photosensitive insulating paste onto the insulating layer. Further, the photosensitive insulating paste layer is irradiated with ultraviolet light or the like through a photomask and developed with an alkaline solution or the like. At this time, the photosensitive insulating paste layer is patterned using a photomask to create openings above the outer electrode conductor layer and vias at the ends of the coil conductor layer.

[0143] Then, a photosensitive conductive paste layer is coated onto the insulating layer having openings and vias, and a coil conductor layer and an external electrode conductor layer are formed through a photolithography process. Specifically, a photosensitive conductive paste with Ag as the main metal component is coated onto the insulating layer by screen printing to fill the openings and vias, forming a photosensitive conductive paste layer. Further, the photosensitive conductive paste layer is irradiated with ultraviolet light or the like through a photomask and developed with an alkaline solution or the like. Thus, an external electrode conductor layer connected to the lower-side external electrode conductor layer via openings and a coil conductor layer connected to the lower-side coil conductor layer via vias are formed on the insulating layer. Additionally, for example, by using a photosensitive conductive paste containing compounds that decompose at a desired firing temperature, voids can be formed within the preform during firing.

[0144] By repeatedly performing the aforementioned processes of forming insulating layers, coil conductor layers, and external electrode conductor layers, a coil consisting of coil conductor layers formed on multiple insulating layers and an external electrode consisting of external electrode conductor layers formed on multiple insulating layers are formed. Furthermore, an insulating layer is formed by repeatedly screen printing insulating paste onto the insulating layer where the coil and external electrode are formed. This insulating layer becomes an outer insulating layer located outside the coil conductor layers. Moreover, if the coil and external electrode are arranged in a matrix on the insulating layer in the above processes, a master layer stack can be obtained.

[0145] Then, the parent laminate is cut into multiple unburned laminates using cutting or other methods. During the cutting process of the parent laminate, the external electrodes are exposed from the parent laminate through the cut surface formed by the cutting. At this time, if a certain amount of cutting deviation occurs, the outer periphery of the coil conductor layer formed in the above process will appear on the end face or bottom face.

[0146] Then, the unfired laminate is fired under specified conditions to obtain a blank containing the coil and external electrodes. Furthermore, firing creates voids within the blank around the coil. The blank is then tumbled and ground to appropriate dimensions, and a Ni plating layer with a thickness of 2μm to 10μm and a Sn plating layer with a thickness of 2μm to 10μm are applied to the portion of the external electrodes exposed from the laminate. Through these processes, an inductor component with a diameter of 0.4mm × 0.2mm × 0.2mm to 0.3mm is completed.

[0147] Furthermore, the method for forming conductor patterns is not limited to the above-described cases. For example, it can be a printing and lamination method using a screen with openings shaped like conductor patterns, a method of patterning conductor films formed by sputtering, vapor deposition, foil lamination, etc., by etching, or a method of forming a negative pattern and then removing unwanted portions after forming a conductor pattern by plating, as in the semi-additive process. Furthermore, achieving a high aspect ratio by forming conductor patterns in multiple stages can reduce losses caused by resistance at high frequencies. More specifically, it can be a process of repeatedly forming conductor patterns as described above, a process of repeatedly overlapping wiring formed by a semi-additive process, a process of forming a portion of a layer by a semi-additive process, a process of forming a plating film by etching, or a combination of processes that further increase the aspect ratio of wiring formed by a semi-additive process through plating growth.

[0148] Furthermore, the conductor material is not limited to the Ag paste described above; any good conductor such as Ag, Cu, or Au formed through sputtering, vapor deposition, foil lamination, or plating is acceptable. Additionally, the methods for forming the insulating layer and the openings / through holes are not limited to the methods described above; openings can also be created by laser processing or drilling after laminating, spin-coating, or spraying the insulating material sheet.

[0149] In addition, the insulating material is not limited to glass or ceramic materials as described above. It can also be organic materials such as epoxy resin, fluororesin, and polymer resin, or composite materials such as glass epoxy resin. However, materials with low dielectric constant and low dielectric loss are preferred.

[0150] Furthermore, the size of the inductor component is not limited to the aforementioned dimensions. Additionally, the method for forming the external electrode is not limited to plating the exposed external conductor after cutting; it can also be a method where, after cutting, the external electrode is further formed by impregnation with conductor paste, sputtering, or the like, and then plating is performed on the external electrode.

Claims

1. An inductor component comprising: blank; A coil, disposed within the aforementioned blank body, and wound axially; and External electrodes, which protrude from the surface of the blank. The aforementioned external electrode is electrically connected to the aforementioned coil. The aforementioned coil has multiple coil wirings wound along a plane orthogonal to the aforementioned axis. Multiple coil wirings are arranged along the aforementioned axial direction and are electrically connected to each other. The aforementioned blank contains voids. The aforementioned gap exists at least within a region of 10 μm from the coil, and also exists in the region where the coil wiring overlaps with the external electrode when viewed from a direction orthogonal to the surface of the substrate on which the external electrode is disposed. On a cross-section parallel to the axis of the coil and orthogonal to the surface of the blank on which the external electrode is provided, the third area ratio is greater than the second area ratio, wherein, The third area ratio is the ratio of the void area in the region where the coil wiring overlaps with the external electrode to the area of ​​the blank when viewed from a direction orthogonal to the surface of the blank. The second area ratio is the ratio of the void area in the region closer to the axial side of the coil than the inner circumferential surface of the coil to the area of ​​the blank.

2. The inductor component according to claim 1, wherein, The size of the aforementioned axial dimension of the aforementioned gap is greater than 0.1 μm and less than 20 μm.

3. The inductor component according to claim 1, wherein, The size of the aforementioned axial dimension of the aforementioned gap is greater than 0.1 μm and less than 10 μm.

4. The inductor component according to any one of claims 1 to 3, wherein, There are multiple such gaps. The multiple gaps mentioned above are separated by a distance of more than 0.1 μm from each other.

5. The inductor component according to any one of claims 1 to 3, wherein, The aforementioned coil has multiple coil wirings wound along a plane orthogonal to the aforementioned axis. Multiple coil wirings are arranged along the aforementioned axial direction and are electrically connected to each other. The aforementioned gaps exist at least in the region between adjacent coil wirings along the aforementioned axial direction.

6. The inductor component according to claim 5, wherein, On the cross section of the shaft containing the aforementioned coil, the first area ratio is greater than the second area ratio, wherein the first area ratio is the ratio of the gap area to the blank area in the region between adjacent coil wirings along the aforementioned axial direction in all coil wirings, and the second area ratio is the ratio of the gap area to the blank area in the region closer to the axial side of the coil than the inner circumferential surface of the aforementioned coil.

7. The inductor component according to claim 6, wherein, The aforementioned first area ratio is 5 / 95 or higher and 50 / 50 or lower. The second area ratio mentioned above is 0 or more and 1 / 99 or less.

8. The inductor component according to any one of claims 1 to 3, wherein, The third area ratio mentioned above is 5 / 95 or higher and 50 / 50 or lower. The second area ratio mentioned above is 0 or more and 1 / 99 or less.

9. The inductor component according to any one of claims 1 to 3, wherein, The aforementioned gap exists at least in a region on the opposite side of the coil's axis from the outer peripheral surface of the coil.

10. The inductor component according to claim 9, wherein, On the cross section of the shaft containing the coil, the fourth area ratio is greater than the second area ratio, wherein the fourth area ratio is the ratio of the void area in the region opposite to the axis of the coil to the blank area, and the second area ratio is the ratio of the void area in the region opposite to the axis of the coil to the blank area.

11. The inductor component according to any one of claims 1 to 3, wherein, The relative permittivity of the above-mentioned blank is above 2.0 and below 8.

0.

12. The inductor component according to any one of claims 1 to 3, wherein, The aforementioned coil is exposed in the aforementioned gap.

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