JP7367447B2 - Coil components and their manufacturing methods, and electronic components mounted with coil components - Google Patents

Description

The present invention relates to a coil component, a method for manufacturing the same, and an electronic component mounted with the coil component.

Conventionally, as a wire-wound coil component, there is one described in, for example, Japanese Patent Application Laid-Open No. 2017-163099 (Patent Document 1). This coil component includes a core having a winding core and a flange formed at both ends of the winding core, an electrode formed on the bottom of the flange, and a core that is connected to the electrode and wound around the winding core. and a wire.

JP 2017-163099 Publication

However, when conventional coil components are mounted and used on a mounting board, the wires may deteriorate and the reliability of the coil component on the mounting board may deteriorate. According to studies conducted by the present inventors, it has been found that when a coil component is mounted on a mounting board, the flux contained in the mounting solder wets and spreads from the electrodes to the core. It has been found that this causes the flux to come into contact with the wire and deteriorate the wire (more specifically, the insulation coating of the wire), reducing the reliability of the coil component.

Therefore, an object of the present disclosure is to provide a coil component and a method for manufacturing the same that suppress flux contained in mounting solder from spreading from electrodes to a core when mounted on a mounting board. Further, another object of the present disclosure is to provide an electronic component mounted with such a coil component.

In order to solve the above problems, a coil component that is one aspect of the present disclosure includes:
A core having a winding core, a first collar formed at a first end of the winding core, and a second collar formed at a second end of the winding core;
a first electrode having a first base electrode formed on the bottom surface of the first flange and a first conductive film formed on the first base electrode;
a second electrode having a second base electrode formed on the bottom surface of the second flange and a second conductive film formed on the second base electrode;
a wire wound around the winding core, a first end connected to the first electrode, and a second end connected to the second electrode;
At least a portion of each of the first flange portion and the second flange portion is coated, and at least a portion of the space between the first base electrode and the first conductive film is coated with the second base electrode and the second base electrode. and an oil-repellent film existing at least partially between the second conductive film and the second conductive film.

According to the embodiment, the oil-repellent film covering the first flange and the second flange allows the flux contained in the mounting solder to be transferred from the first electrode and the second electrode to the core when the coil component is mounted on the mounting board. It can prevent the product from getting wet and spreading. Thereby, for example, in the mounted coil component, it is possible to suppress the wire from coming into contact with the flux and deteriorating the wire. As a result, the reliability of the coil components on the mounting board is improved.

Further, a method for manufacturing a coil component, which is one aspect of the present disclosure, includes:
a core preparation step of preparing a core having a winding core, a first flange formed at a first end of the winding core, and a second flange formed at a second end of the winding core;
a base electrode forming step of forming a first base electrode on the bottom surface of the first flange and forming a second base electrode on the bottom surface of the second flange;
an oil-repellent film forming step of forming an oil-repellent film on at least a portion of each of the first flange portion and the second flange portion, and at least a portion of each of the first base electrode and the second base electrode;
a first conductive film is formed on the first base electrode, a first electrode having the first base electrode and the first conductive film is formed on the bottom surface of the first flange, and the second base electrode is formed on the bottom surface of the first flange; a conductive film forming step of forming a second conductive film on the electrode, and forming a second electrode having the second base electrode and the second conductive film on the bottom surface of the second flange;
The method includes a wire winding step of winding a wire around the winding core, connecting a first end of the wire to the first electrode, and connecting a second end of the wire to the second electrode.

According to the embodiment, in the oil-repellent film forming step, at least a portion of each of the first flange portion and the second flange portion and at least a portion of each of the first base electrode and the second base electrode are collectively coated. Since it can form an oil-repellent film, the manufacturing process can be streamlined. In addition, by coating the vicinity of the first base electrode of the first flange part and the vicinity of the second base electrode of the second flange part with an oil-repellent film, the first and second electrodes of the mounting solder can be coated with the oil-repellent film when mounting the coil component. It is possible to reliably suppress the spread of wetness from the core to the core.

Further, an electronic component that is one aspect of the present disclosure is
comprising a mounting board and the coil component mounted on the mounting board,
The first electrode and the second electrode are connected to the wiring of the mounting board via solder,
The solder flux does not adhere to the first flange and the second flange.

According to the embodiment, solder flux does not adhere to the first flange and the second flange. Thereby, even if the electronic component is used for a long period of time, it is possible to suppress the wire from coming into contact with the flux and deteriorating the wire. This provides electronic components with excellent long-term reliability.

According to the present disclosure, it is possible to provide a coil component that suppresses flux contained in mounting solder from spreading from an electrode to a core when mounted on a mounting board, and a method for manufacturing the same. Further, according to the present disclosure, it is possible to provide an electronic component in which such a coil component is mounted.

FIG. 2 is a side view showing a coil component according to the first embodiment. It is a sectional view showing a coil component concerning a 1st embodiment. It is a sectional view showing a manufacturing method of a coil component concerning a 1st embodiment. It is a sectional view showing a manufacturing method of a coil component concerning a 1st embodiment. It is a sectional view showing a manufacturing method of a coil component concerning a 1st embodiment. It is a sectional view showing a manufacturing method of a coil component concerning a 1st embodiment. It is a sectional view showing a manufacturing method of a coil component concerning a 1st embodiment. FIG. 7 is a sectional view showing a coil component according to a second embodiment. FIG. 7 is a side view showing an electronic component according to a third embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a coil component, a method for manufacturing the same, and an electronic component mounted with the coil component, which are one aspect of the present disclosure, will be described in detail with reference to illustrated embodiments. Note that some of the drawings are schematic and may not reflect actual dimensions and proportions.

(First embodiment)
FIG. 1 is a side view showing a coil component according to a first embodiment of the present disclosure. FIG. 2 is a sectional view showing the coil component according to the first embodiment. The coil component will be explained using FIGS. 1 and 2. For convenience of explanation, the oil-repellent film is omitted in FIG. 1, and the wires, top plate, and adhesive layer are omitted in FIG. FIG. 2 is a cross section in a plane that includes the winding axis and extends in the vertical direction.

The coil component 1 includes a core 10, a wire 20 wound around the core 10, a first electrode 31 and a second electrode 32 provided in the core 10 and to which the wire 20 is electrically connected and which serve as external terminals. The core 10 includes an oil-repellent film 40 that covers at least a portion of the core 10 and is present inside the first electrode 31 and the second electrode 32 , and a top plate 15 that is attached to the core 10 . Hereinafter, the core will be described with the bottom side as the lower side and the top side as the upper side.

The core 10 has a shape extending in a certain direction, and is formed at a winding core part 13 around which the wire 20 is wound and a first end 13a in the extending direction of the winding core part 13, and has a first end 13a extending in a direction perpendicular to the winding core part 13. The winding core 13 has a first flange 11 and a second flange 12 that is formed at the second end 13b in the direction in which the winding core 13 extends and projects in a direction perpendicular to the direction. The material of the core 10 is preferably a magnetic body such as a sintered body of ferrite or a molded body of resin containing magnetic powder, and may also be a non-magnetic body such as alumina or resin. Note that, hereinafter, the bottom surface of the core 10 will be referred to as the surface to be mounted on the mounting board, and the surface opposite to the bottom surface of the core 10 will be referred to as the top surface of the core 10. Core 10 preferably includes ferrite.

The first flange portion 11 has a first bottom surface 11a on the side to be mounted on the mounting board, and a first top surface 11b located on the opposite side of the first bottom surface 11a. The second flange portion 12 has a second bottom surface 12a on the side to be mounted on the mounting board, and a second top surface 12b located on the opposite side of the second bottom surface 12a.

The top plate 15 is provided on the first top surface 11b of the first flange 11 and the second top surface 12b of the second flange 12 via an adhesive layer 16. The material of the top plate 15 is, for example, the same as that of the core 10. When the core 10 and the top plate 15 are both magnetic, they form a closed magnetic path, and the efficiency of acquiring the inductance of the coil component 1 is improved. Further, since the coil component 1 can be moved by adsorbing the top plate 15 with an external device, for example, when mounting the coil component 1 on a mounting board, the coil component 1 can be easily placed at a desired position. I can do it.

The wire 20 is wound around the winding core 13 , the first end 21 is connected to the first electrode 31 , and the second end 22 is connected to the second electrode 32 . The winding axis (coil axis) of the wire 20 coincides with the direction in which the winding core extends. The wire 20 is a conductive wire with an insulating coating, in which a conductive wire made of a metal such as copper is covered with a coating made of a resin such as polyurethane or polyamideimide. The wire 20 and the electrodes 31 and 32 are connected by, for example, thermocompression bonding, brazing, welding, or the like.

The first electrode 31 is provided on the first bottom surface 11a of the first collar portion 11. The first electrode 31 includes a first base electrode 311 formed on the first bottom surface 11a of the first flange 11 and a first conductive film 312 formed on the first base electrode 311. The second electrode 32 is provided on the second bottom surface 12a of the second collar portion 12. The second electrode 32 includes a second base electrode 321 formed on the second bottom surface 12a of the second flange 12 and a second conductive film 322 formed on the second base electrode 321.

The first base electrode 311 is, for example, a sintered body obtained by baking a conductive paste such as Ag glass paste applied by a dip method. Since the first base electrode 311 is a sintered body, the strength and impact resistance of the first base electrode 311 itself can be ensured, and the adhesion force between the first base electrode 311 and the first collar portion 11 can be ensured. Preferably, the first base electrode 311 contains glass and Ag. According to this, the strength and impact resistance of the first base electrode 311 itself can be further ensured, and the adhesion force between the first base electrode 311 and the first flange 11 can be further ensured.

On the other hand, the first conductive film 312 is, for example, a metal film formed by plating. When the first conductive film 312 is a metal film, it can be made thinner and the influence on the mounting area of the mounting board can be reduced. The metal film may be a multilayer metal film in which a plurality of metal films are stacked. The multilayer metal film is, for example, a three-layer metal film consisting of a Cu layer with low electrical resistance and excellent stress resistance, a Ni layer with excellent corrosion resistance, and a Sn layer with excellent solder wettability. At this time, it is preferable that the Cu layer, Ni layer, and Sn layer are arranged in order from the inside to the outside.

Although the configuration of the first electrode 31 has been described above, in the coil component 1, the second electrode 32 has the same configuration as the first electrode 31. According to this, since the second electrode 32 has the same configuration as the first electrode 31, the adhesion force between the coil component 1 and the mounting board is further improved, and the degree of freedom in design and the ease of manufacturing are further improved. improves. However, the structure is not limited to the above structure, and either one of the first and second electrodes 31 and 32 may have the above structure.

The oil-repellent film 40 has flux-repellent properties that repel flux in the mounting solder. The oil-repellent film 40 covers at least a portion of each of the first flange portion 11 and the second flange portion 12, and also covers at least a portion between the first base electrode 311 and the first conductive film 312 and the second flange portion 12. It exists in at least a portion between the base electrode 321 and the second conductive film 322. Thereby, when mounting the coil component 1 on the mounting board, it is possible to suppress the flux contained in the mounting solder from wetting and spreading from the first electrode 31 and the second electrode 32 to the core 10. Thereby, for example, in the mounted coil component 1, it is possible to suppress the wire 20 from coming into contact with the flux and deteriorating the wire 20. As a result, the reliability of the coil component 1 on the mounting board is improved.

The oil-repellent film 40 includes, for example, a fluororesin and a silicone resin, preferably includes a fluororesin (more specifically, polyfluoroether, etc.), and is more preferably made of a fluororesin. When the oil-repellent film 40 contains a fluororesin, the oil-repellent film 40 can be formed by fluoridation treatment, so that the coil component 1 is excellent in mass productivity. The melting point of the material constituting the oil-repellent film 40 is, for example, 240°C to 260°C.

The oil-repellent film 40 exists discontinuously and partially between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322, respectively. This increases the contact area between the first base electrode 311 and the first conductive film 312 and the contact area between the second base electrode 321 and the second conductive film 322. Therefore, the adhesion between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322 is improved to ensure electrical connection. In addition, since the surfaces of the first and second base electrodes 311 and 321 are partially exposed from the oil-repellent film 40, the first conductive film 312 and the second conductive film 322 are coated on the first base electrode 311 by plating. It can be formed on the surface and on the surface of the second base electrode 321.

The aspect in which the oil-repellent film 40 exists discontinuously and partially on the surfaces of the first and second base electrodes 311 and 321 as described above depends on, for example, the material of the oil-repellent film 40 and the first and second base electrodes 311, 321, 321 material, the drying conditions for the oil-repellent paste coating in the oil-repellent film forming process (more specifically, drying temperature, drying time, etc.) and the viscosity of the oil-repellent paste in the oil-repellent film forming process described below, and the wire winding process described later. It can be controlled by the temperature at which the wire 20 is thermocompression bonded to the first and second electrodes 31 and 32.

The oil-repellent film 40 discontinuously partially covers the surface of the first flange 11 other than the first top surface 11b that is exposed from the winding core 13 and the first electrode 31, and The surface of the second flange 12 other than the second top surface 12b that is exposed from the winding core 13 and the second electrode 32 is discontinuously and partially covered. When the oil-repellent film 40 is discontinuous and partially covers the first and second flanges 11 and 12, the surface area of the coil component 1 increases. In other words, the creepage distance of the surface of the coil component 1, which can serve as a path for the flux to wet and spread, increases. Thereby, when mounting the coil component 1 on a mounting board, the flux contained in the mounting solder is difficult to reach the wire 20 via the surfaces of the first and second collar parts 11 and 12.

The manner in which the oil-repellent film 40 discontinuously and partially covers the first and second flanges 11 and 12 and the winding core 13 may be due to, for example, the combination of the material of the oil-repellent film 40 and the material of the core 10, or the repellent material described later. It can be controlled by the drying conditions (more specifically, drying temperature, drying time, etc.) of the coating film of the oil-repellent paste in the oil-film forming step and the viscosity of the oil-repellent paste.

The oil-repellent film 40 exists in a region between the winding core 13 and the first electrode 31 in the first flange 11 and in a region between the winding core 13 and the second electrode 32 in the second flange 12. Exists in the area of As a result, when the coil component 1 is mounted on the mounting board, the flux contained in the mounting solder is spread between the wire 20 and the first and second flanges 11 and 12, and between the first and second flanges 11 and 12. It can effectively suppress creeping up on itself. Moreover, in the mounted coil component 1, it is possible to suppress the wire 20 from coming into contact with flux and deteriorating.

The first adhesion amount per fixed area of the oil-repellent film 40 existing between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322 is It is smaller than the second adhesion amount per certain area of the oil-repellent film 40 on the surfaces of the portion 11 and the second flange portion 12. In other words, the oil-repellent film 40 is unevenly distributed on the surfaces of the first and second brim portions 11 and 12 compared to the areas between the base electrodes 311 and 321 and the conductive films 312 and 322.

In this specification, a certain area is a certain length (unit length) or a certain area (unit area). The constant length refers to a constant length in a line corresponding to the surfaces of the flanges 11 and 12 in the same cross section, and a constant length in a line corresponding to the surfaces of the base electrodes 311 and 321. Specifically, as shown in FIG. 2, the surfaces of the flanges 11 and 12 have a constant length in cross section, and the surfaces of the base electrodes 311 and 321 have a constant length. The constant area refers to a constant area on the surfaces of the flanges 11 and 12 and a constant area on the surfaces of the base electrodes 311 and 321.

Since the first adhesion amount is smaller than the second adhesion amount, the contact area between the first base electrode 311 and the first conductive film 312 and the contact area between the second base electrode 321 and the second conductive film 322 increase. Therefore, the adhesion between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322 is improved to ensure electrical connection. On the other hand, since the second adhesion amount is larger than the first adhesion amount, the area of the oil-repellent film 40 covering the surfaces of the first and second collar portions 11 and 12 increases. Therefore, when mounting the coil component 1 on a mounting board, it is possible to suppress the flux contained in the mounting solder from wetting and spreading from the first electrode 31 and the second electrode 32 to the core 10. Thereby, for example, in the mounted coil component 1, it is possible to further suppress the wire 20 from coming into contact with the flux and deteriorating the wire 20. As a result, the reliability of the coil component 1 on the mounting board is further improved.

Here, a method of calculating the first and second adhesion amounts based on a fixed length will be explained. Cutting the coil component 1 at the center of the first and second electrodes 31 and 32, for example, as shown in FIG. 2, cutting the coil component 1 along a plane that includes the winding axis of the wire 20 and extends in the vertical direction Form a cross section. Capture a SEM image of the cross section. In the SEM image, the length of the surface of the base electrode 311, 321 covered with the oil-repellent film 40 is measured at a certain length of the surface of the base electrode 311, 321. For example, the lengths are measured at a plurality of fixed lengths, and the average value is taken as the first adhesion amount. The second adhesion amount was determined by changing the measured length to the length of the surfaces of the flanges 11 and 12 covered with the oil-repellent film 40 at a constant length on the surfaces of the flanges 11 and 12 in the same cross section. It is calculated in the same manner as the calculation method of 1 adhesion amount.

Next, a method of calculating the first and second adhesion amounts based on a fixed area will be explained. SEM images (more specifically, three-dimensional SEM images) of the surfaces of the base electrodes 311 and 321 and the surfaces of the flanges 11 and 12 are taken, respectively. The area of the surface of the base electrode 311, 321 covered with the oil-repellent film 40 is measured at a certain area of the surface of the base electrode 311, 321. For example, the area is measured in a plurality of fixed areas, and the average value is taken as the first adhesion amount. The second adhesion amount was calculated using the same method as the first adhesion amount, except that the area to be measured was changed to the area of the surfaces of the flanges 11 and 12 covered with the oil-repellent film 40 in a constant area of the surfaces of the flanges 11 and 12. Calculate in the same way.

The oil-repellent film 40 further covers at least a portion of the core portion 13 . If at least a portion of the winding core 13 is coated with the oil-repellent film 40, the flux may get wet and spread in the winding core 13 around which the wire 20 is wound when the coil component 1 is mounted on the mounting board. suppress. This makes it difficult for the wire 20 wound around the winding core 13 to get wet by the flux, thereby further suppressing deterioration of the wire 20 and further improving the reliability of the coil component 1.

The oil-repellent film 40 is not present on the top surfaces 11b and 12b of the first flange 11 and the second flange 12, respectively. Since the oil-repellent film 40 is not present on the top surfaces 11b, 12b of the first flange 11 and the second flange 12, adhesive can be applied to the top surfaces 11b, 12b, as shown in FIG. Thereby, the top plate 15 can be placed on the top surfaces 11b and 12b.

(Manufacturing method of coil parts)

An example of a method for manufacturing the coil component 1 according to this embodiment will be described with reference to FIGS. 3A to 3E. 3A to 3E are cross sections for explaining a method of manufacturing the coil component 1. FIG. The method for manufacturing the coil component 1 includes a core preparation process, a base electrode formation process, an oil-repellent film formation process, a conductive film formation process, a wire winding process, and a top plate formation process.

As shown in FIG. 3A, in the core preparation step, the core 10 is prepared. For example, the core 10 is formed by connecting the first flange 11 to the first end 13a of the core 13 and connecting the second flange 12 to the second end 13b of the core 13. Thereby, the core 10 has the winding core 13, the first flange 11 formed at the first end 13a of the winding core 13, and the second flange 12 formed at the second end 13b of the winding core 13. Prepare.

As shown in FIG. 3B, in the base layer forming step, a first base electrode 311 is formed on the first bottom surface 11a of the first flange 11, and a second base electrode 321 is formed on the second bottom surface 12a of the second flange 12. Form. For example, a conductive paste is applied to the bottom surfaces 11a and 12a of each of the first and second flange parts 11 and 12 by a dip method, and the applied film is baked. As a result, first and second base electrodes 311 and 321 are formed. The conductive paste includes, for example, glass and conductive powder. The conductive powder is, for example, Ag powder.

As shown in FIG. 3C, in the oil-repellent film forming step, at least a portion of each of the first flange 11 and the second flange 12 and at least a portion of each of the first base electrode 311 and the second base electrode 321 are An oil-repellent film 40 is formed on the surface. For example, an oil-repellent paste is applied to the core 10 provided with the base electrodes 311 and 321 by a dip method, and the applied film is dried. This forms an oil-repellent film 40. In the oil-repellent film forming step, at least a portion of each of the first flange portion 11 and second flange portion 12 and at least a portion of each of the first and second base electrodes 311 and 321 are collectively formed into an oil-repellent film 40. can be formed. Therefore, the manufacturing process can be streamlined. Furthermore, by covering the vicinity of the first and second base electrodes 311 and 321 with the oil-repellent film 40, when mounting the coil component 1, the wetting of the mounting solder from the first and second electrodes 31 and 32 to the core 10 is prevented. The spread can be definitely suppressed.

The oil-repellent paste contains an oil-repellent resin. The oil-repellent resin is, for example, a fluororesin and a silicone resin, preferably a fluororesin (more specifically, polyfluoroether). When the oil-repellent paste contains a fluororesin as the oil-repellent resin, the oil-repellent film 40 can be formed by fluorination treatment. Thereby, the oil-repellent film 40 can be easily formed on a portion of the first and second base electrodes 311 and 321.

In the oil-repellent film forming step, a coating film is formed on the first top surface 11b of the first flange 11 and the second top surface 12b of the second flange 12. As a result, the oil-repellent film 40 that does not exist on the top surfaces 11b, 12b of the first flange 11 and the second flange 12 is formed. Thereby, the top plate 15 can be connected to the top surfaces 11b and 12b using adhesive in the subsequent top plate forming process.

In the oil-repellent film forming step, the oil-repellent film 40 is partially formed on each of the first and second base electrodes 311, 321 and the winding core 13. The aspect of such a partially formed oil-repellent film 40 depends on, for example, the combination of the oil-repellent resin and the material of the core 10, the drying conditions (more specifically, drying temperature, drying time, etc.), and the oil-repellent paste. can be controlled by adjusting the viscosity of

As shown in FIG. 3D, in the conductive film forming step, first and second conductive films 312 and 322 are formed to form first and second electrodes 31 and 32, respectively. Specifically, the first conductive film 312 is formed on the first base electrode 311 by plating, and the first electrode 31 having the first base electrode 311 and the first conductive film 312 is attached to the first base electrode 311 of the first flange 11. It is formed on the bottom surface 11a. A second conductive film 322 is formed on the second base electrode 321 by plating, and a second electrode 32 having the second base electrode 321 and the second conductive film 322 is formed on the second bottom surface 12a of the second flange 12. . In the oil-repellent film forming step, the oil-repellent film 40 is partially formed on the first and second base electrodes 311 and 321, so the oil-repellent film 40 is formed so that the first and second base electrodes 311 and 321 are exposed. Therefore, in the subsequent conductive film forming step, the first conductive film 312 can be formed on the first base electrode 311 and the second conductive film 322 can be formed on the second base electrode 321 by plating.

In the wire winding step, the wire 20 is wound around the winding core 13, the first end 21 of the wire 20 is connected to the first electrode 31, and the second end 22 of the wire 20 is connected to the second electrode 32. . The first and second ends 21 and 22 of the wire 20 are connected to the first and second electrodes 31 and 32, respectively, by, for example, thermocompression bonding, brazing, welding, or the like. In thermocompression bonding, as shown in FIG. 3E, heat is applied to the first end 21 of the wire 20 in contact with the first electrode 31 and the second end 22 of the wire 20 in contact with the second electrode 32. 1. Apply to the second electrodes 31 and 32. The thermocompression bonding temperature is, for example, 400°C to 500°C. Note that in FIG. 3E, the wire 20 wound around the winding core 13 is omitted.

When the ends 21 and 22 are connected to the electrodes 31 and 32 by thermocompression bonding, it is preferable that the thermocompression bonding temperature is equal to or higher than the melting point of the material forming the oil-repellent film 40. When the thermocompression bonding temperature is equal to or higher than the melting point of the material constituting the oil-repellent film 40, each remaining between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322 At least a portion of the oil-repellent film 40 can be removed. As a result, the contact area between the first base electrode 311 and the first conductive film 312 and the contact area between the second base electrode 321 and the second conductive film 322 are increased, and the contact area between the first base electrode 311 and the first conductive film 312 is increased. The adhesion between the second base electrode 321 and the second conductive film 322 can be improved, and electrical connection can be ensured. As a result, the formation accuracy and reliability of the first and second conductive films 312 and 322 are improved.

In the top plate forming step, the top plate 15 is formed on the top surfaces 11b and 12b of the first and second flange portions 11 and 12, respectively. For example, the top plate 15 is connected by applying adhesive to the top surfaces 11b, 12b of the first and second flanges 11, 12. In addition, although the method for manufacturing the coil component 1 has been described as including a top plate forming process, the top plate forming process may not be included.

(Second embodiment)
FIG. 4 is a sectional view showing a second embodiment of the coil component. Similar to FIG. 2, FIG. 4 omits the wire 20, top plate 15, and adhesive layer 16 for convenience of explanation. The second embodiment differs from the first embodiment in the manner in which the oil-repellent film covers. This different configuration will be explained below. Note that in the second embodiment, the same reference numerals as those in the first embodiment have the same configurations as in the first embodiment, so the description thereof will be omitted.

As shown in FIG. 4, in the coil component 1A of the second embodiment, the oil-repellent film 40A is formed on the core portion 13 and the first portion of the first flange portion 11 other than the first top surface 11b. Covers all the surfaces exposed from the electrode 31, and covers all the surfaces other than the second top surface 12b of the second flange 12 that are exposed from the winding core 13 and the second electrode 32. The entire surface of the winding core 13 exposed from each of the first flange 11 and the second flange 12 is covered. The oil-repellent film 40A increases the area covering the first flange 11 and the second flange 12, so that when the coil component 1A is mounted on the mounting board, the flux contained in the mounting solder spreads to the first and second electrodes. 31 and 32 to the first flange 11 and second flange 12, respectively. The coating with such an oil-repellent film 40A can be achieved, for example, by selecting an oil-repellent resin that has a high affinity for the core 10 or by using an oil-repellent paste in the oil-repellent film forming step of the method for manufacturing the coil component 1A. This can be achieved by increasing the viscosity of

The oil-repellent film 40A partially exists between the first base electrode 311 and the first conductive film 312 and between the second base electrode 321 and the second conductive film 322. For example, in the oil-repellent film forming process, even if the entire surface of the base electrodes 311, 321 is covered with the oil-repellent film 40A together with the entire surface of the core 10 other than the top surfaces 11b, 12b, for example, after the oil-repellent film 40 is formed, the base electrodes 311, 321 are covered with the oil-repellent film 40A. By applying heat to the electrodes 311 and 321 in advance, the above partially existing mode can be realized.

(Third embodiment)
FIG. 5 is a side view showing a third embodiment of the electronic component. The third embodiment differs from the first embodiment in that the coil component 1 of the first embodiment is an electronic component mounted on a mounting board. This different configuration will be explained below. Note that in the third embodiment, the same reference numerals as those in the first embodiment have the same configurations as in the first embodiment, so the description thereof will be omitted. Further, in FIG. 5, like FIG. 1, the oil-repellent film 40 is omitted for convenience of explanation.

As shown in FIG. 5, the electronic component 100 of the third embodiment includes a mounting board 101 and the coil component 1 of the first embodiment mounted on the mounting board 101. The first electrode 31 and the second electrode 32 are connected to the wiring of the mounting board 101 via the solder 110. Flux 111 of solder 110 is not attached to first flange 11 and second flange 12 .

Flux 111 of solder 110 does not adhere to first flange 11 and second flange 12 . Thereby, even if the electronic component 100 is used for a long period of time, it is possible to suppress the wire 20 from coming into contact with the flux 111 and deteriorating the wire 20. Therefore, the electronic component 100 has excellent long-term reliability. Although the flux 111 covers the entire surface of the solder 110, it may partially cover the solder 110.

In the embodiment, the number of wires 20 is one, but the number is not limited to this. When there are two wires 20, the coil component 1 can be a common mode choke coil. Specifically, when there are two wires 20, the first collar part 11 has two legs on the first bottom surface 11a side, one leg is provided with the first electrode, and the other leg is provided with the first electrode. A third electrode is provided on the foot. The second flange portion 12 has two legs on the second bottom surface 12a side, one leg is provided with a second electrode, and the other leg is provided with a fourth electrode. A first end of one wire (first wire) is connected to the first electrode, and a second end is connected to the second electrode. The first end of the other wire (second wire) is connected to the third electrode, and the second end is connected to the fourth electrode.

The present disclosure is not limited to the first to third embodiments, and can be implemented in various forms without changing the gist of the present disclosure. Further, the configurations shown in the first to third embodiments are merely examples and are not particularly limited, and various changes can be made without substantially departing from the effects of the present disclosure. For example, the items described in the first to third embodiments can be combined as appropriate. For example, the configuration described in the second embodiment and the configuration described in the third embodiment can be combined. More specifically, in the third embodiment, the coil component 1A of the second embodiment can be mounted in place of the coil component 1 of the first embodiment.

1 Coil parts 10 Core 11 First flange 11a First bottom 11b First top 12 Second flange 12a First bottom 12b First top 13 Winding core 13a First end 13b Second end 15 Top plate 20 Wire 21 First end 22 Second end 31 First electrode 311 First base electrode 312 First conductive film 32 Second electrode 321 Second base electrode 322 Second conductive film 40 Oil-repellent film 100 Electronic component 101 Mounting board 110 Solder 111 flux

Claims (12)

A core having a winding core, a first collar formed at a first end of the winding core, and a second collar formed at a second end of the winding core;
a first electrode having a first base electrode formed on the bottom surface of the first flange and a first conductive film formed on the first base electrode;
a second electrode having a second base electrode formed on the bottom surface of the second flange and a second conductive film formed on the second base electrode;
a wire wound around the winding core, a first end connected to the first electrode, and a second end connected to the second electrode;
At least a portion of each of the first flange portion and the second flange portion is coated, and at least a portion of the space between the first base electrode and the first conductive film is coated with the second base electrode and the second base electrode. an oil-repellent film existing at least partially between the second conductive film and the second conductive film ;
The oil-repellent film is a coil component containing a fluororesin . A core having a winding core, a first collar formed at a first end of the winding core, and a second collar formed at a second end of the winding core;
a first electrode having a first base electrode formed on the bottom surface of the first flange and a first conductive film formed on the first base electrode;
a second electrode having a second base electrode formed on the bottom surface of the second flange and a second conductive film formed on the second base electrode;
a wire wound around the winding core, a first end connected to the first electrode, and a second end connected to the second electrode;
At least a portion of each of the first flange portion and the second flange portion is coated, and at least a portion of the space between the first base electrode and the first conductive film is coated with the second base electrode and the second base electrode. an oil-repellent film existing at least partially between the second conductive film and the second conductive film ;
A coil component, wherein the oil-repellent film is partially discontinuously present between the first base electrode and the first conductive film and between the second base electrode and the second conductive film. The oil-repellent film is present in a region between the core portion and the first electrode in the first flange portion, and in a region between the core portion and the second electrode in the second flange portion. The coil component according to claim 1 or 2 , which exists in the region of. The first adhesion amount per fixed area of the oil-repellent film existing between the first base electrode and the first conductive film and between the second base electrode and the second conductive film is The coil component according to any one of claims 1 to 3 , wherein the second adhesion amount of the oil-repellent film per certain area on the surface of the flange portion and the second flange portion is smaller than the second adhesion amount. The coil component according to any one of claims 1 to 4 , wherein the oil-repellent film further covers at least a portion of the winding core. The coil component according to any one of claims 1 to 5 , wherein the oil-repellent film is not present on the top surface of each of the first flange portion and the second flange portion. The oil-repellent film covers all surfaces of the first flange other than the top surface of the first flange that are exposed from the winding core and the first electrode, and covers the entire surface of the first flange that is exposed from the winding core and the first electrode. Covering all surfaces other than the surface exposed from the winding core part and the second electrode in the second collar part, and from each of the first collar part and the second collar part in the winding core part. The coil component according to any one of claims 1 to 6 , which covers all exposed surfaces. The coil component according to any one of claims 1 to 7 , further comprising a top plate on the top surface of the first flange and the second flange. a core preparation step of preparing a core having a winding core, a first flange formed at a first end of the winding core, and a second flange formed at a second end of the winding core;
a base electrode forming step of forming a first base electrode on the bottom surface of the first flange and forming a second base electrode on the bottom surface of the second flange;
an oil-repellent film forming step of forming an oil-repellent film on at least a portion of each of the first flange portion and the second flange portion, and at least a portion of each of the first base electrode and the second base electrode;
a first conductive film is formed on the first base electrode, a first electrode having the first base electrode and the first conductive film is formed on the bottom surface of the first flange, and the second base electrode is formed on the bottom surface of the first flange; a conductive film forming step of forming a second conductive film on the electrode, and forming a second electrode having the second base electrode and the second conductive film on the bottom surface of the second flange;
a wire winding step of winding a wire around the winding core, connecting a first end of the wire to the first electrode, and connecting a second end of the wire to the second electrode ,
In the wire winding step, the first end of the wire is thermocompression bonded to the first electrode, and the second end of the wire is thermocompression bonded to the second electrode,
A method for manufacturing a coil component , wherein the thermocompression bonding temperature is higher than the melting point of the material constituting the oil-repellent film . The method for manufacturing a coil component according to claim 9 , wherein the oil-repellent film is formed by fluorination treatment. In the oil-repellent film forming step, the oil-repellent film is partially formed on each of the first base electrode and the second base electrode,
The coil component according to claim 9 or 10 , wherein in the conductive film forming step, the first conductive film is formed on the first base electrode by plating, and the second conductive film is formed on the second base electrode. manufacturing method. comprising a mounting board and the coil component according to any one of claims 1 to 8 mounted on the mounting board,
The first electrode and the second electrode are connected to the wiring of the mounting board via solder,
The electronic component, wherein the solder flux does not adhere to the first flange and the second flange.

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