This application claims the benefit of priority to Korean Patent Applications No. 10-2016-0142182, filed on Oct. 28, 2016, and No. 10-2016-0152020, filed on Nov. 15, 2016, with the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entireties.
The present disclosure relates to a coil component and, more particularly, to a thin film power inductor.
Recently, with a continued trend in the miniaturization and thinning of smartphones and wearable devices, chip size in power inductors has been reduced, and composite materials using magnetic metallic materials have been used in power inductors to achieve high efficiency.
Efforts have been undertaken on miniaturized power inductors to provide characteristics, such as high capacity and low direct current resistance (RDC), due to the limitations of chip size. For example, the content of a magnetic material is increased for the same chip size by changing a C-shaped external electrode extending to an upper surface of a conventional chip to an L-shaped external electrode not extending to the upper surface of the conventional chip. However, notwithstanding this effort, the problems caused by delamination, due to difficulties in securing adhesion between heterogeneous materials or by an increase in the content of magnetic materials, have not been solved.
An aspect of the present disclosure may provide a coil component that may increase a level of inductance by increasing a space which may be filled with a magnetic material, while having a reduced chip size.
According to an aspect of the present disclosure, a coil component may include a body including a coil and a magnetic material, and an external electrode disposed on at least a portion of an external surface of the body and having an internal surface contacting and electrically connected to the coil. The coil includes at least one lead portion. A support member may be disposed in the body to support the coil, and at least a portion of a surface of the support member facing toward the internal surface of the external electrode may include a machined surface.
According to another aspect of the present disclosure, a coil component may include a body including a coil, the coil including a coil body and at least one lead portion connected to the coil body. The coil component further includes an external electrode disposed on at least a portion of an external surface of the body and electrically connected to the at least one lead portion of the coil. The body may further include a support member, the coil is disposed on one surface of the support member, and an outer boundary surface of the support member may be spaced apart from a junction portion between the external electrode and the at least one lead portion at a predetermined interval.
According to a further aspect of the present disclosure, a coil component includes a support member having a surface with a coil disposed thereon, a body formed of a magnetic material, and an external electrode disposed on an external surface of the body and contacting a lead portion of the coil. The support member and coil are disposed within the body. A thickness of the support member, measured orthogonally to the surface of the support member having the coil disposed thereon, is smaller at a position closer to the external electrode than at a position further from the external electrode.
According to a further aspect of the present disclosure, a coil component includes a support member having a coil disposed thereon, a body formed of a magnetic material, and an external electrode disposed on an external surface of the body and contacting a lead portion of the coil. The support member and coil are disposed within the body. A surface of the support member facing the external surface of the body having the external electrode includes at least two protrusions separate from each other and extending towards the external surface of the body.
According to another aspect of the present disclosure, a coil component includes a support member having a coil disposed thereon, a body formed of a magnetic material, and an external electrode disposed on an external surface of the body and contacting a lead portion of the coil. The support member and coil are disposed within the body. Additionally, a surface of the support member facing the external surface of the body having the external electrode is coplanar with an outermost coil pattern of the coil body.
The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description, taken in conjunction with the accompanying drawings, in which:
Hereinafter, embodiments of the present disclosure will be described with reference to the attached drawings.
The present disclosure may, however, be exemplified in many different forms and should not be construed as being limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
Throughout the specification, it will be understood that when an element, such as a layer, region, or wafer (substrate), is referred to as being “on, ” “connected to, ” or “coupled to” another element, it can be directly “on,” “connected to,” or “coupled to” the other element, or other elements intervening therebetween may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element, there may be no other elements or layers intervening therebetween. Like numerals refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated, listed items.
It will be apparent that, although the terms ‘first,’ ‘second,’ third,' etc. may be used herein to describe various members, components, regions, layers, and/or sections, these members, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one member, component, region, layer, or section from another member, component, region, layer, or section. Thus, a first member, component, region, layer, or section discussed below could be termed a second member, component, region, layer, or section without departing from the teachings of the exemplary embodiments.
Spatially relative terms, such as “above,” “upper,” “below,” and “lower” and the like, may be used herein for ease of description to describe one element's positional relationship relative to other element(s) in the illustrative orientation shown in the figures. However, it will be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “above” or “upper” relative to other elements would then be oriented “below” or “lower” relative to the other elements or features. Thus, the term “above” can encompass both the above and below orientations, depending on a particular directional orientation of the figures. The device may also be oriented otherwise (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may be interpreted accordingly.
The terminology used herein describes particular embodiments only, and the present disclosure is not limited thereby. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, members, elements, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, members, elements, and/or groups thereof.
Hereinafter, embodiments of the present disclosure will be described with reference to schematic views shown in the drawings and illustrating embodiments of the present disclosure. In the drawings, components having ideal shapes are shown. However, variations from these ideal shapes, for example due to variability in manufacturing techniques and/or tolerances, also fall within the scope of the disclosure. Thus, embodiments of the present disclosure should not be construed as being limited to the particular shapes of regions shown herein, but should more generally be understood to include changes in shape resulting from manufacturing methods and processes. The following embodiments may also be constituted alone or as a combination of several or all thereof.
The contents of the present disclosure described below may have a variety of configurations, and only an illustrative configuration is proposed herein, but the present disclosure is not limited thereto.
Hereinafter, a coil component according to an embodiment will be described, but the present disclosure is not limited thereto.
As illustrated in
When the end portion of the side surface of the support member C12 supporting the coil C11 is in contact with the first and second external electrodes C21 and C22, adhesion between an electrode paste used in forming the first and second external electrodes C21 and C22 and the support member C12 may be poor. Thus, when the first and second external electrodes C21 and C22 are plated, delamination thereof may occur frequently. Further, considering a common manufacturing process of a coil component, a support member and a coil pattern may be embedded in a magnetic material, and then the magnetic material may be diced to expose a lead portion of the coil pattern. When a dicing blade is in contact with the support member, a difficult-to-machine material included in the support member, for example, a glass frit or the like, may quicken abrasion of the dicing blade.
A coil component 100 according to an embodiment may be designed to solve the above issues and may provide various effects in addition to solving the above-mentioned issues.
Referring to
The body 1 may form the overall exterior of the coil component 100, may have an upper surface and a lower surface opposing each other in a thickness direction T, a first side surface and a second side surface opposing each other in a length direction L, and a first cross section and a second cross section opposing each other in a width direction W, and may have a substantially hexahedral shape. However, the present disclosure is not limited thereto.
The body 1 may include a magnetic material having magnetic characteristics. For example, the magnetic material may be formed by incorporating ferrite or magnetic metallic particles in a resin. The magnetic metallic particles may include at least one selected from the group consisting of iron (Fe), silicon (Si), chromium (Cr), aluminum (Al), and nickel (Ni).
The first and second external electrodes 21 and 22, disposed on the at least a portion of the external surface of the body 1, may be illustrated in
The first and second external electrodes 21 and 22 may be electrically connected to a coil 11 included in the body 1, and thus may include, for example, a material having excellent electrical conductivity. The first and second external electrodes 21 and 22 may be formed of, for example, nickel (Ni), copper (Cu), silver (Ag), or alloys thereof, and may also include multiple layers (e.g., multilayers). In some cases, each of the first and second external electrodes 21 and 22 may be formed by forming a wiring plated with copper (Cu) in an innermost portion thereof and then disposing a plurality of plating layers on the formed wiring. However, materials and formation methods of the first and second external electrodes 21 and 22 are not limited thereto.
When viewed from the inside of the body 1, the body 1 may include the coil 11 buried by the magnetic material and a support member 12 supporting the coil 11. The coil 11 may include an upper coil 111 disposed on the upper surface of the support member 12 and a lower coil 112 disposed on the lower surface of the support member 12. The upper and lower coils 111 and 112 may be electrically connected to each other through a via (not illustrated) extending through the support member 12. However, the present disclosure is not limited thereto. For example, a plurality of upper coils may also be disposed on only the upper surface of the support member 12 or, alternatively, it may be sufficient to include at least one coil supported by the support member 12.
The coil 11 may have an overall spiral shape, but the present disclosure is not limited thereto. Further, the coil 11 may include a metallic material having excellent electrical conductivity, for example, copper (Cu).
The coil 11 may include a first lead portion 11a connected to the first external electrode 21 and a second lead portion 11b connected to the second external electrode 22. A coil region of the upper coil 111 of the coil 11, excluding the first lead portion 11a, may be a coil body 111c, and a coil region of the lower coil 112 of the coil 11, excluding the second lead portion 11b, may be a coil body 112c.
The support member 12 supporting the coil 11 will be described below.
The support member 12 may be provided to form the coil 11, having a further reduced thickness, and to form the coil 11 more easily, and may be an insulating substrate formed of an insulating resin. The insulating resin may include a thermosetting resin such as an epoxy resin, a thermoplastic resin such as a polyimid, or a resin in which a stiffener such as a glass fiber or an inorganic filler is impregnated such as a pre-preg, an Ajinomoto build-up film (ABF), a FR-4 resin, a bismaleimide triazine (BT) resin, or a photoimageable dielectric (PID) resin. When the support member 12 includes glass fiber, stiffness of the support member 12 may be increased.
The support member 12 may have a through hole H formed in a central portion thereof (e.g., a central portion in which the coil 11 is not disposed). The through hole H may be filled with the magnetic material (e.g., the same magnetic material used to form the body 1) to form a core portion of a magnetic core, and may increase permeability of the coil component 100.
Referring to
With regard to a thickness of the support member 12, a minimum thickness (T1.min) of the portion of the support member 12 disposed below at least a region of a lower surface of the first lead portion 11a of the coil 11, may be less than a minimum thickness (T2.min) of the portion of the support member 12 disposed below at least a region of a lower surface of an innermost coil pattern of the coil 11. This means that, in some examples, a part of the support member 12, disposed below the at least a region of the lower surface of the first lead portion 11a of the coil 11, has been removed.
Referring to
Referring to
In the coil component 100 according to an embodiment, the support member 12 may include the machined surface 12a in a side portion thereof contacting the first external electrode 21. As such, an area in which the internal surface 21a of the first external electrode 21 and the support member 12 are in contact with each other may be significantly reduced.
Generally, the support member 12 maybe formed of a material having insulating characteristics. As a result, the support member 12 may have poor affinity with a conductive material of the first external electrode 21. As a result, when the support member 12 is bonded to the first external electrode 21, a delamination phenomenon may occur frequently, in which the first external electrode 21 may be separated from the support member 12 in a bonding region therebetween. As in the coil component 100, because the support member 12 has a thinned profile at a side surface contacting the first external electrode 21, the area of the junction portion having poor affinity may be reduced to avoid the delamination phenomenon, thus increasing structural reliability.
As illustrated in
Further, just as a material such as a glass fabric or the like may often be included in the support member 12, the support member 12 may include a difficult-to-machine material. However, in the coil component 100 according to this embodiment, the outer surface of the support member 12 exposed to an outer portion of the body 1, along with the first lead portion 11a of the coil 11, may have a relatively small area. As a result, when the coil component 100 is diced into individual chips, a contact area between a dicing blade and the support member 12 may be significantly reduced. As such, a possibility that the dicing blade is in contact with the difficult-to-machine material may be significantly reduced; thus, a rate at which the dicing blade wears may be significantly decreased.
Region C, indicated by the dashed line in
Subsequently, modifications of a detailed shape of the machined surface 12a of the support member 12 of
Referring to
The concave slit shape may have a substantially overall “U” shape, as illustrated in
Subsequently, referring to
The coil component 200 of
Referring to
Referring to
The body 31 may have a coil 311 embedded therein, and the coil 311 may include a first lead portion 311a, connected to the first external electrode 321, and a second lead portion 311b, connected to the second external electrode 322. The coil 311 may include an upper coil 3111 and a lower coil 3112, but the present disclosure is not limited thereto.
As illustrated in
Further, a support member maybe disposed on a lower surface of the upper coil 3111 and an upper surface of the lower coil 3112, and an outer boundary surface of the support member may be spaced apart from an internal surface of the first external electrode 321 and/or an internal surface of the second external electrode 322, at a predetermined interval E. In more detail, the outer boundary surface of the support member may be spaced apart from a junction portion in which the first external electrode 321 may be connected to the first lead portion 311a, and/or spaced apart from a junction portion in which the second external electrode 322 may be connected to the second lead portion 311b. This means that a portion of the support member has been removed, unlike the initial support member, which extended to the junction portion.
Thus a region E, from which the portion of the support member has been removed, may be filled with a magnetic material, and a margin portion may be secured, to increase permeability of the coil component 300.
As illustrated in
Referring to
The insulating layer 513 may be disposed on a lower surface of a first lead portion 511a of the coil 511 and an upper surface of a second lead portion 511b of the coil 511, of the external surface of the coil 511. Since lower surfaces of lead portions of a coil in a thin film inductor according to the related art are in contact with a substrate supporting the lead portions, there is no need or room to include an additional coated insulating layer. However, in the case of the coil component according to this embodiment, the portion of the support member adjacent to the junction portion, in which the external electrode maybe connected to the lead portion of the coil, on the outer boundary surface of the support member, may be removed. Thus, the insulating layer may be additionally disposed on the remainder of the support member and on the lead portion of the coil not supported by the remainder of the support member.
As set forth above, according to the embodiments, a level of inductance of a coil component may be increased by removing unnecessary insulating material and filling the resulting margin portion with a magnetic material. Further, the bonding force of an external electrode, which is generally poor in bonding force with respect to the insulating material, in the coil component may be remarkably increased by removing the unnecessary insulating material.
While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present invention, as defined by the appended claims.
Number | Date | Country | Kind |
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10-2016-0142182 | Oct 2016 | KR | national |
10-2016-0152020 | Nov 2016 | KR | national |