KR101736592B1

KR101736592B1 - Inductance element and electronic device

Info

Publication number: KR101736592B1
Application number: KR1020150131759A
Authority: KR
Inventors: 아키라 사토; 료 나카바야시
Original assignee: 알프스 덴키 가부시키가이샤
Priority date: 2014-10-03
Filing date: 2015-09-17
Publication date: 2017-05-16
Also published as: JP6339474B2; CN105529134B; CN105529134A; JP2016076559A; KR20160040422A; TWI614773B; TW201614689A

Abstract

[PROBLEMS] To provide an inductance element in which insulation of the surface of a magnetic member is enhanced while suppressing influence on magnetic properties.
[MEANS FOR SOLVING PROBLEMS] A magnetic member (1) comprising a molded body containing a ferromagnetic metal powder containing Fe and an insulating layer formed on a surface portion of the molded body, and a conductive member having a portion located inside the magnetic member (3b) formed on the surface of the magnetic member (1) in a state of being electrically connected to the conductive member (2), and the insulating layer is made of a phosphate Inductance element (10).

Description

TECHNICAL FIELD [0001] The present invention relates to an inductance element and an electronic device.

The present invention relates to an inductance element having a magnetic member, a conductive member, and a connection end, and an electronic apparatus in which the inductance element is mounted.

BACKGROUND ART [0002] In recent years, miniaturization of electronic devices has progressed, and the mounting space of electronic components tends to be small. On the other hand, the performance required for electronic devices is diversified, such as high-speed, multi-function, and power saving. In order to meet these demands, the number of electronic components to be mounted on the electronic apparatus tends to increase. Therefore, the demand for miniaturization of electronic parts has been particularly high in recent years.

In order to appropriately meet such a demand, the materials constituting the electronic component are positively reviewed so that the function of the electronic component is not deteriorated by miniaturization of the electronic component. For example, conventionally, ferrite powders have been used as the magnetic material included in the magnetic member included in the inductance element, which is one type of electronic component. However, in recent years, the saturation magnetic flux density is larger than that of the ferrite powder, The ferromagnetic metal powder is used.

As such a ferromagnetic metal powder, a soft magnetic alloy powder such as Fe-based amorphous alloy powder, Fe-Ni-based alloy powder, Fe-Si-based alloy powder and pure iron powder (high purity iron powder) can be exemplified. As a specific example, in Patent Document 1, the composition formula is represented by Fe _100-abcxyzt Ni _a Sn _b Cr _c P _x C _y B _z Si _t , where 0 at% ≤ a ≤ 10 at%, 0 at% <c ≤ 3 at Z, at% ≤ t ≤ 1 at%, and the amount of addition of z + Si (%) of B is 6.8 at% ≤ x ≤ 10.8 at%, 2.2 at% ≤ y ≤ 9.8 at%, 0 at% ≤ z ≤ 4 at% Of the amorphous Fe-based amorphous alloy is in the range of 1 at% to 4 at% and the glass transition temperature (Tg) is 710 K or less. In Patent Document 2, the additive A has a composition of Ni: 41 wt% or more and less than 45 wt%, additive A: 1 wt% or more and 5 wt% or less and the balance: Fe and inevitable impurities, Mo-based soft magnetic alloy powder which is at least one of Mo, Cr and Cu.

Japanese Patent Publication No. 5419302 Japanese Patent Application Laid-Open No. 2007-254814

An inductance element having a magnetic member having a molded body containing a ferromagnetic metal powder as disclosed in the above-mentioned Patent Document and having a plurality of conductive connecting ends on its surface is formed of a magnetic material It is required that the surface of the member has a proper insulating property.

Particularly, in the case where a member constituting the conductive connecting end is to be formed by electroplating, it is preferable that the surface of the magnetic member has sufficient insulating property as will be described later. That is, when the plating layer is formed on the surface of the magnetic member by electroplating, a metallization layer made of conductive paste or the like is formed on a part of the surface of the magnetic member before electroplating, The energizing area is made. When the surface of the magnetic member has a sufficient insulating property, the electric force line from the anode reaches the energizing region of the surface of the magnetic member when electroplating is performed, and a plating layer can be selectively formed on the energizing region.

However, when forming the ferromagnetic metal powder, it is generally known that the granulated powder mixed and compounded with a binder resin such as acrylic resin or silicone resin and the ferromagnetic metal powder is molded by pressing in a molding die or the like. In this case, the insulation of the surface of the molded body is mainly retained by the binder resin. When the molded body is molded, the molded metal mold and the above-mentioned granulated powder are rubbed to expose the surface of the ferromagnetic metal powder on the surface of the molded body. As a result, the magnetic member may not be able to maintain sufficient insulation. In such a case, when electroplating is performed, an electric force line from the anode reaches a region (adjacent region) adjacent to the energizing region on the surface of the magnetic member. As a result, the plating layer is evacuated from the energizing area, and is also formed in the adjacent area.

When the so-called " plating elongation " phenomenon occurs, the shape of the conductive layer viewed from the plane differs from the shape of the metallized layer seen from the plane, resulting in appearance defects in the inductance element. When the amount of elongation of the plating is large, the plating layer is formed so as to electrically short-circuit the current-carrying regions formed on the surface of the magnetic member so as not to contact each other, and the inductance element can not perform its function adequately.

In view of such a phenomenon, it is an object of the present invention to provide an inductance element in which the surface of a magnetic member has a high insulation property. It is another object of the present invention to provide an electronic device in which the above-described inductance element is mounted.

As a result of the studies by the present inventors, it has been found that the above problems can be solved by providing the phosphate layer formed by the phosphate treatment on the insulating layer located in the surface layer of the magnetic member.

One aspect of the present invention, which is provided based on the above-described new findings, relates to a magnetic member comprising a molded body containing a ferromagnetic metal powder containing Fe and an insulating layer formed on a surface portion of the molded body, And an electrically conductive connecting end portion formed on the surface of the magnetic member in a state of being electrically connected to the electrically conductive member, wherein the insulating layer is an inductance element having a phosphate layer formed by a phosphate treatment.

Since the phosphate treatment includes the dissolution of Fe located on the surface of the member to be treated among the ferromagnetic metal powders constituting the formed body in a small process, the portion exposed to the surface of the shaped body of the ferromagnetic metal powder preferentially forms the phosphate layer . For this reason, the thickness of the phosphate layer can be an insulating layer which appropriately insulates the molded body, while having a thickness of submicron or less.

When the ferromagnetic metal powder contains Fe as a main component, it is preferable that the ferromagnetic metal powder reacts well with Fe to form a phosphate layer. Therefore, the ferromagnetic metal powder preferably contains Fe as a main component.

The connecting end of the inductance element may be provided with a plating layer. The plating layer may be formed by electroplating on the metallization layer formed on the insulating layer.

The magnetic member of the above-described inductance element may have a hole.

The insulating layer of the above-described inductance element may include an impregnated coat layer. In this case, the mechanical strength of the formed body is improved, and problems such as cracking or chipping of the molded body are hardly generated.

Another aspect of the present invention is an electronic device in which the above-described inductance element is mounted.

In the inductance element according to the above invention, since the insulating layer of the magnetic member has the phosphate layer, the insulating property of the surface of the magnetic member can be enhanced. According to the present invention, an electronic device in which the above-described inductance element is mounted is also provided.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a part of an overall configuration of an inductance element according to an embodiment of the present invention. Fig.
Fig. 2 is a view showing one cross-sectional observation result of the inductance element manufactured by the first embodiment.
3 is a view showing one cross-sectional observation result of the inductance element manufactured by Comparative Example 1. Fig.
Fig. 4 is a view showing one appearance observation result of the inductance element manufactured by the comparative example 1, in which the phenomenon of " plating elongation "
5 is a view showing one appearance observation result of the inductance element manufactured by the first embodiment.
6 is a graph showing the results of Test Example 5. Fig.

Hereinafter, a case where the inductance element is the inductance element 10 shown in Fig. 1 will be described as a specific example with respect to the embodiment of the present invention.

1. Inductance element

1, an inductance element 10 according to an embodiment of the present invention includes a magnetic member 1, a conductive member 2, and two connection ends 3a and 3b. The magnetic member (1) has a molded body and an insulating layer. The conductive member (2) has a portion located inside the magnetic member (1). Specifically, in the inductance element 10 shown in Fig. 1, a coil is embedded in a molded body of the magnetic member 1. [ The conductive connecting ends 3a and 3b are formed on the surface of the magnetic member 1 in a state of being electrically connected to the conductive member 2. [

The size of the inductance element 10 according to the embodiment of the present invention is not limited. As will be described later, the insulating property of the surface of the magnetic member 1 of the inductance element 10 according to the embodiment of the present invention is sufficiently high, and its size is 2 mm x 1.6 mm, . The distance between the connection ends 3a and 3b may be 1 mm or less.

Hereinafter, the molded body, the insulating layer, the conductive member 2, and the connecting ends 3a and 3b of the magnetic member 1 will be described.

(1) Magnetic member

(1-1) Molded body

The shaped body contains a ferromagnetic metal powder containing Fe. As long as Fe is contained, the kind of the ferromagnetic metal powder is not limited. As described above, examples of the ferromagnetic metal powders include Fe-based amorphous alloy powder, Fe-Ni-based alloy powder, Fe-Si-based alloy powder, and soft magnetic alloy powder such as pure iron powder (high purity iron powder). Particularly, when a phosphate layer is formed by a phosphate treatment described later, Fe contained in the ferromagnetic metal powder reacts to form a phosphate layer. From the viewpoint of promoting this reaction efficiently, it is preferable that the ferromagnetic metal powder is one containing Fe as a main component. Since the ferromagnetic metal powder has high conductivity, it is difficult to ensure the insulating property of the surface of the molded body when the outermost surface of the formed body is made of the ferromagnetic metal powder. For this reason, an insulating layer made of an oxide layer or the like may be formed on the surface of the soft magnetic alloy powder by any means in the powder step. Phosphate is a compound mainly containing Fe, P, O, and M (= Fe, Zn, Mn, Ca, etc.).

The molded product may contain an organic component. The organic component is preferably capable of functioning as a binder for binding the ferromagnetic metal powder to each other. The specific composition of the organic component having such a binding function is not limited. The organic-based component may contain a resin material. Examples of the resin material include a silicone resin, an epoxy resin, a phenol resin, a melamine resin, a urea resin, an acrylic resin, and an olefin resin. The organic-based component may contain a substance in which the above-mentioned resin material is subjected to heat treatment. The composition of such a material can be adjusted according to the composition of the resin material subjected to the heat treatment, the heat treatment conditions, and the like. It is preferable that the organic-based component can make the ferromagnetic metal powder contained in the formed body electrically independent of each other. The resin material related to the organic component may be composed of one kind or a plurality of kinds. For example, the resin material related to the organic component may be a mixture of a thermosetting resin such as a phenol resin and a thermoplastic resin such as an acrylic resin.

In the case where the molded article contains an organic component, the content of the organic component in the molded article is not limited. When the organic component has a binding function, it is preferable to contain an amount such that the function is properly exhibited. In addition, when the content of the organic component is excessively high, the content of the organic component in the molded article is set in consideration of the fact that the magnetic property of the magnetic member 1 including the molded article tends to be lowered .

The molded article may contain a substance other than the ferromagnetic metal powder and the organic component. As such materials, insulating inorganic components such as glass and alumina; A coupling agent for improving the adhesion between the ferromagnetic metal powder and the organic component, such as a silane coupling agent, and the like. The content of these substances in the molded article is not limited.

The molded body may have a cavity. The formation process of this public is not limited. And may be formed by springback after molding, or may be formed by annealing the molded product obtained by molding as described later. When the molded body has a pore, the insulation between the ferromagnetic powders in the molded body is improved, and the magnetic property of the magnetic member 1 tends to be improved. However, if the density of the presence of vacancies in the formed body is excessively high, the degree of binding between the ferromagnetic powders in the formed body is lowered, and the mechanical strength of the magnetic member 1 is lowered. Therefore, when the molded article has a cavity, it is preferable that the porosity (the percentage of the volume of the cavity portion defined as the portion in which the solid material does not exist in the molded article is equal to or less than 3% % Or less.

(1-2) Insulating layer

The insulating layer is formed on the surface of the molded body and, if necessary, on portions near the surface (these are collectively referred to as " surface portions " in this specification) so that the surfaces of the magnetic members 1 are insulating. The magnetic member 1 according to one embodiment of the present invention has a phosphate layer whose insulating layer is formed by a phosphate treatment.

The kind of the metal ion used for the phosphate treatment is not limited. Iron, manganese, zinc, calcium, and the like. The phosphate treatment involves dissolving a metallic material, particularly Fe, located on the surface of the member to be treated as its minor process. By the reaction in which hydrogen molecules are formed from hydrogen ions positioned as counter reactions of the dissolution reaction of the metallic material, the pH of the processing solution located in the vicinity of the portion where the metallic material is dissolved is increased. In a region where the pH of the treatment liquid is increased, the metal ions (including ions generated by dissolution of the metal material) contained in the treatment liquid react with phosphoric acid to generate an insoluble phosphate. This poorly soluble phosphate precipitates on the member to be treated to form a phosphate layer.

Therefore, the phosphate layer is preferentially formed in the exposed portion of the metallic material containing Fe, that is, the ferromagnetic metal powder in the magnetic member which is the member to be treated in the phosphate treatment. Therefore, the phosphate layer can efficiently form an insulating layer.

Even if the thickness of the phosphate layer is thick, it is on the order of several tens nm, and it is not easy to confirm the phosphate layer even by observing a cross section using an electron microscope (see FIG. 2). However, as described above, since the exposed portion of the ferromagnetic metal powder containing Fe is preferentially insulated, the phosphate layer can be an insulating layer having excellent insulating function. The reaction for forming the phosphate layer as described above proceeds efficiently when the ferromagnetic metal powder contains Fe as a main component.

It is preferable that the insulating layer is formed so as to cover the ferromagnetic metal powder (hereinafter also referred to as " surface powder ") located on the outermost surface of the formed body. The surface powder may come into contact with other members during the manufacturing process after the molding process by rubbing against the surface of the mold when the surface powder is taken out from the forming mold by the spring back after the molding, thereby exposing the surface made of the metallic material. Even in such a case, since the ferromagnetic metal powder contains Fe, the insulating layer can be preferentially formed on the surface of the metallic material in the surface powder by performing the phosphate treatment. Therefore, as the insulating layer is provided with the phosphate layer, the insulating property of the surface of the magnetic member 1 can be increased.

The insulation resistance of the insulation layer is 5 x 10 < ¹¹ > OMEGA or more as measured by measurement of the insulation resistance described later. With this level of insulation resistance, in the case of forming the plating layer on the magnetic member 1 by the electroplating process, the plating material is not precipitated well except the energizing region formed on the magnetic member 1 by the metallization layer or the like , The possibility of occurrence of " plating extension " phenomenon can be more stably reduced.

The insulating layer may include an impregnated coat layer. By providing the impregnated coat layer, the mechanical strength of the magnetic member 1 can be improved. The surface of a molded article having a structure in which the surface powder is bound or the surface powder is bound by an organic component or the like may have a degree of irregularity depending on the particle size distribution of the ferromagnetic metal powder. In such a case, it is not easy to form a phosphate layer so as to cover the entire surface powder. Therefore, the impregnation-coated layer is first formed on the surface of the molded article to reduce the degree of irregularity on the surface of the phosphate layer to be formed (the molded article on which the impregnated coat is formed) and then the phosphate layer is formed to cover the surface powder with the phosphate layer It becomes easy. Therefore, the impregnated coat layer may be formed so as to cover the entire surface of the surface powder, or the surface of the surface powder may have a portion not covered by the impregnated coat layer. In either case, it is only necessary to reduce the degree of irregularity of the surface of the phosphate layer to be formed by forming the impregnated coat layer.

However, in the case where there is no such problem, the impregnated coat layer may be formed after forming the phosphate layer. In either case, the phosphate layer may cover the ferromagnetic metal powder exposed on the surface of the molded body.

The type of the impregnated coat layer is not limited. Silicone resins, acrylic resins, butyralphenol resins, epoxy resins, and the like. It is preferable that the impregnated coat layer contains a silicone resin in view of a relatively low possibility of causing a bad result in a process (particularly a dry process) for forming an inorganic insulating layer.

In the prior art, the insulating layer may consist of only such impregnation coat. However, when the inductance element such as the inductance element 10 shown in Fig. 1 is particularly reduced in size (specifically, 2 mm x 1.6 mm, about 1 mm in height or less) It is difficult to form the impregnated coat layer with high uniformity on the surface portion of the molded article even if the coatability is increased. As described above, when the molded body has a cavity, the impregnated coating composition seeps into the cavity, the surface of the molded body is partially exposed, and the impregnated coat layer is not uniformly formed on the surface portion of the molded body, (Hereinafter also referred to as a " low-insulating region " in the present specification) that does not have sufficient insulating properties may be generated on the surface of the magnetic member provided on the surface. As described above, such a low-insulating region can cause the phenomenon of " plating extension ". Therefore, if the amount of the impregnating coating composition used for forming the impregnated coat layer is increased so as to reduce the possibility of occurrence of the low-insulating region, the amount of shrinkage when the impregnated coat layer is formed with the impregnated coat composition increases. As a result, the ferromagnetic metal powder in the inductance element may be easily deformed due to the shrinkage. The deformation generated in the ferromagnetic metal powder may cause the magnetic properties of the inductance element to deteriorate.

On the other hand, in the inductance element 10 according to the embodiment of the present invention, the possibility that a low-insulating region is generated on the surface of the magnetic member 1 is sufficiently reduced because the insulating layer includes the phosphate layer. Therefore, even if the size of the inductance element 10 is particularly reduced, problems such as " plating elongation on the surface of the magnetic member 1 "

(2) The conductive member

The shape and composition of the conductive member 2 are not limited as long as the conductive member 2 can be embedded in the inside of the magnetic member 1. In the case of the inductance element 10 shown in Fig. 1, the conductive member 2 has a coil-shaped portion. The specific shape of the coil is not limited. For example, the coil may be an edge-wise coil. It is preferable that the conductive member 2 is made of a material having high conductivity containing copper, aluminum, or the like.

(3)

The connection ends 3a and 3b are electrically conductive members formed on the surface of the magnetic member 1 in a state of being electrically connected to the end portions 2a and 2b of the conductive member 2. [ The connecting ends 3a and 3b are usually formed on a plurality of regions of the surface of the magnetic member 1. [ The inductance element 10 shown in Fig. 1 has two connection ends 3a and 3b. The shape and composition of the connection ends 3a and 3b are not limited as long as the connection ends 3a and 3b have appropriate conductivity and the plurality of connection ends 3a and 3b on the surface of the magnetic member 1 are not short- Do not.

In the inductance element 10 shown in Fig. 1, the connection ends 3a and 3b include a metallization layer formed of a conductive paste such as silver paste and a plating layer formed on the metallization layer, from the viewpoint of productivity. The material for forming the plating layer is not limited. Examples of the metal element contained in the material include copper, aluminum, zinc, nickel, iron and tin.

Even if the above-mentioned plating layer is formed by electroplating, the surface of the magnetic member 1 according to the embodiment of the present invention has sufficient insulating property, so that the phenomenon of " plating elongation "

The thickness and size (shape) of the connecting end portions 3a and 3b are to be appropriately set. As described above, when the connection ends 3a and 3b are provided with the metallization layer and the plating layer, the amount of the conductive paste for forming the metallization layer is about 0.05 g / cm 2, and the range of the thickness of the plating layer 3 To about 13 mu m can be exemplified.

2. Manufacturing method of inductance element

The manufacturing method of the inductance element 10 according to the embodiment of the present invention is not particularly limited. It is possible to efficiently manufacture the inductance element 10 according to the embodiment of the present invention.

In one example, a manufacturing method of the inductance element 10 according to an embodiment of the present invention includes a forming step, a phosphate treatment step, and a connection end forming step, and as a preferable example, an annealing process is performed between the forming step and the phosphating step And a further impregnation coating process may be provided.

In the molding step, a mixture containing the ferromagnetic metal powder and the binder component is molded. The binder component is not limited, and resin materials such as a silicone resin, an epoxy resin, a phenol resin, a melamine resin, a urea resin, an acrylic resin, and an olefin resin can be exemplified. The mixture may further contain an insulating inorganic component, a coupling agent, a lubricant (zinc stearate, aluminum stearate, etc. may be mentioned), and the like. The method of preparing the mixture is arbitrary. And the mixture may be mixed using a ball mill or the like. The dispersion containing the respective components may be adjusted, and the dispersion may be dried and pulverized to obtain a mixture as a granulated powder containing the ferromagnetic metal powder. Molding conditions are also not limited. And pressurization is carried out at room temperature in the range of about 0.1 to 5 것을.

In the molding step, the conductive member 2 such as a coil is disposed in the cavity of the molding die and molded to embed the conductive member 2 in the molded product.

An annealing process may be performed to anneal the molded product obtained by the molding process, if necessary. By performing the annealing treatment, the deformation in the ferromagnetic metal powder generated by the forming step is relaxed, and the magnetic property of the magnetic member 1 can be improved. The conditions of the annealing treatment are suitably set in consideration of the degree of deformation generated in the ferromagnetic metal powder and the thermal characteristics of the binder component. For example, heating at a heating rate of 20 ° C / minute to 50 ° C / minute from room temperature to 300 ° C to 500 ° C, and maintaining the heating temperature for 0.5 hours to 5 hours can be cited.

The impregnated coating step may be performed on the formed body obtained through the annealing step before the phosphate treatment step. In the impregnation coating step, the composition is impregnated into the surface layer of the molded article by bringing the impregnated coating composition into contact with the molded body. The contact method is not limited. The molded article may be dipped in the impregnated coating composition, or the impregnated coating composition may be applied to the molded article. When the molded article is immersed in the impregnated coating composition, the impregnated coating composition can be easily introduced into the molded article by immersing the molded article while evacuating the vacuum. An impregnated coat layer is obtained by drying the impregnated coating composition impregnated in the surface layer of the formed article, or performing treatment such as heating as required. By forming the impregnated coat layer, the degree of irregularity of the surface of the formed body on which the impregnated coat layer is formed, which is an object of the phosphate treatment process, is reduced, and a phosphate layer having excellent insulating properties is easily formed in the phosphate treatment process. The composition of the impregnated coating composition is not limited. A silicone resin, an acrylic resin, a butyral phenol resin, and an epoxy resin. The impregnation coating process may be performed after the phosphate treatment.

In the phosphate treatment step, the molded body is subjected to a phosphate treatment to form an insulating layer containing a phosphate layer to obtain a magnetic member 1 having a molded body and an insulating layer. In the case where the annealing process is carried out as described above, the formed article is obtained by annealing the molded article obtained by the forming step. When the annealing step is not carried out, the formed article is formed by the molded article obtained by the molding step . In addition, even when the impregnation coating process is performed as described above, the reaction for forming the phosphate layer includes the dissolution of Fe contained in the ferromagnetic metal powder into the reaction process as described above. Therefore, the phosphate layer is not formed on the impregnated coat layer, and is selectively formed on the ferromagnetic metal powder exposed on the surface of the formed body. In this case, the insulating layer is provided with the impregnated coat layer and the phosphate layer. On the other hand, when the impregnation coating process is performed after the phosphate treatment process, the impregnated coat layer may be formed on the phosphate layer. When the impregnation coating process is not carried out, the insulating layer has a phosphate layer.

The treatment liquid (phosphate treatment solution) used for the phosphate treatment contains phosphate ions and appropriate metal ions. Examples of metal ions include, but are not limited to, iron ions, manganese ions, zinc ions, and calcium ions. The liquor of the phosphoric acid treatment liquid is not limited and may be acidic. The phosphoric acid treatment liquid may contain an organic acid or the like.

The conditions of the phosphoric acid treatment are appropriately set in accordance with the composition of the molded article to be treated and the composition of the phosphoric acid treatment liquid. The temperature of the phosphoric acid treatment solution may be in the range of about room temperature (25 캜) to about 60 캜. The treatment time is suitably set in accordance with the treatment temperature and the like. It may be performed within a range of several tens of seconds to several minutes.

A step for forming a member constituting the insulating layer may be performed after the phosphating step. As such a process, for example, a process for forming an organic-based coat layer may be performed or a process for forming a fluorine-based coat layer may be performed.

When the magnetic member 1 having the insulating layer on the surface layer is thus obtained, the connection ends 3a and 3b electrically connected to the conductive member 2 disposed in the magnetic member 1 are connected to the magnetic member 1 1) is formed on the insulating layer. When the connecting ends 3a and 3b are composed of a metallization layer and a plating layer, first, a conductive paste such as silver paste is applied on the insulating layer. The application method is arbitrary. Printing, and dispenser are preferably used. And if necessary, is dried to form a metallized layer on the insulating layer. Subsequently, an electroplating process is performed to form a plating layer on the metallization layer. The electroplating method is not limited. As described above, when the size of the inductance element 10 is particularly small, it is preferable to conduct barrel plating. In the method of manufacturing the inductance element 10 according to the embodiment of the present invention, since the insulating layer has the inorganic insulating layer, when the electroplating is performed, the plating layer is released from the metallized layer, (&Quot; plating extension " phenomenon) formed on the insulating layer is hardly generated.

The manufacturing method of the inductance element 10 according to the embodiment of the present invention described above can be summarized as follows. That is, a manufacturing method of an inductance element having a magnetic member having a molded body and an insulating layer and a conductive connection end, the method comprising: a molding step of molding a mixture containing a ferromagnetic metal powder containing Fe and a binder component; A phosphate treatment step of performing a phosphate treatment on a molded body obtained through a molding process to obtain a magnetic member having a molded body and an insulating layer; And a connecting end forming step of forming a connecting end on the insulating layer of the magnetic member. The inductance element described above can be efficiently manufactured by this method.

In the above-described manufacturing method, an annealing step may be provided for annealing the molded product obtained by the forming step.

In the manufacturing method described above, the conductive layer includes a metallization layer formed of a conductive paste and a plating layer formed on the metallization layer, and the connection end forming step is a step of forming a metallization layer by coating the conductive paste on the insulating layer , And electroplating to form a plating layer on the metallization layer.

In the manufacturing method described above, the magnetic member may have a conductive member inside, and the connection end may be formed so as to be electrically connected to the conductive member in the connection end forming step.

3. Electronic devices

The inductance element 10 according to the embodiment of the present invention does not cause a short circuit at the connection ends 3a and 3b even if the inductance element 10 is particularly small. Therefore, the inductance element 10 according to the embodiment of the present invention is particularly excellent in operation stability even if it is small. Therefore, the electronic device in which the inductance element 10 according to the embodiment of the present invention is mounted can be easily miniaturized. In addition, it is possible to mount a plurality of inductance elements 10 in a mounting space of the electronic device. With respect to this point, it is possible to downsize the power supply switching circuit, the voltage raising and lowering circuit, the smoothing circuit, the circuit for blocking the high-frequency current, etc., by making the inductance element 10 small. Therefore, it is easy to increase the power supply circuit of the electronic apparatus. As a result, more precise power control becomes possible, and power consumption of the electronic apparatus can be suppressed. The inductance element 10 included in the electronic device may be one manufactured by the manufacturing method of the inductance element 10 described above.

The embodiments described above are provided for the purpose of facilitating understanding of the present invention and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design modifications and equivalents falling within the technical scope of the present invention.

For example, the inductance element may be provided with a magnetic member and a conductive member, or may be an inductor, a reactor, or a transformer.

In the above description, the conductive member is embedded in the inside of the molded body during the manufacturing step of the molded body, but a plurality of molded bodies may be disposed so as to enclose the conductive member. More specifically, it is preferable that one of the formed bodies has a groove portion in which the conductive member can be arranged, and a conductive member is disposed in the groove portion, and then another molded body is disposed so as to cover the conductive member, Thereby obtaining a structure.

[Example]

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to these Examples and the like.

(Example 1)

The Fe-based amorphous soft magnetic powder obtained by weighing the Fe-based amorphous soft magnetic powder to a composition of Fe _{74.43 at%} Cr _{1.96 at%} P _{9.04 at%} C _{2.16 at%} B _{7.54 at%} Si _{4.87 at%} using a water _atomization method as a ferromagnetic metal powder . The particle size distribution of the obtained soft magnetic powder was measured by volume distribution using "Microtrack particle size distribution measuring apparatus MT3300EX" manufactured by Nikkiso Co., Ltd. As a result, the average particle diameter (D50) was 5.0 占 퐉.

2 parts by mass of a binder containing a resin material containing a phenolic resin as an acrylic resin as a thermoplastic resin and 0.3 part by mass of a lubricant as a zinc stearate were mixed to obtain a slurry.

The obtained slurry was pulverized after being dried, and fine powders of 300 μm or less and coarse powders of 850 μm or more were removed using a mesh of 300 μm and a diameter of 850 μm to obtain granulated powder.

The granules obtained by the method described above were filled in a metal mold preliminarily placed in a cavity of an insulating coated copper coil (number of turns: 5) and pressure-molded under the conditions of a mold temperature of 23 캜 and a surface pressure of 1.0 ㎬, &Lt; / RTI >

The obtained molded product was placed in a furnace in a nitrogen atmosphere and heated from room temperature (25 DEG C) to 370 DEG C at a heating rate of 40 DEG C / min, maintained at this temperature for 60 minutes, Thereafter, a heat treatment was performed in which the furnace was cooled to room temperature. Thus, a rectangular parallelepiped body having a size of 2 mm x 1.6 mm and a thickness of 1 mm was obtained.

An iron phosphate treatment solution for precipitation of a phosphate coating was prepared. The above-mentioned shaped body was immersed in the phosphoric acid treatment solution maintained at a constant liquid temperature for several seconds to several minutes. The molded article after immersion was washed with water and dried to obtain a magnetic member having a molded body and an insulating layer composed of a phosphate layer on the surface portion thereof.

A metalization layer made of a silver paste was formed by printing on each of the opposite faces having a size of 1.6 mm x 1 mm of the magnetic member and having a shape of 2 mm x about 0.5 mm in a plan view.

A barrel plated metal (Ni / Sn) was applied to the magnetic member having the obtained metallization layer to form a Ni plating base layer having a thickness of about 2 占 퐉 and a Sn plating layer having a thickness of about 6 占 퐉.

Thus, a magnetic member comprising a molded body containing a ferromagnetic metal powder and an organic component composed of an amorphous soft magnetic powder, and an insulating layer having a phosphate layer formed on the surface portion of the molded body; A conductive member having a portion (coil) located inside the formed body of the magnetic member; And a conductive connection end portion formed on the surface of the magnetic member and having a metallization layer based on silver paste and a Ni / Sn plated layer, thereby obtaining an inductance element having an external appearance as shown in Fig.

(Comparative Example 1)

An inductance element was fabricated in the same manner as in Example 1 except that no insulating layer was formed.

(Test Example 1) Observation of the cross section of the inductance element

The inductance element manufactured by the example was buried in a resin and cut, and the cut surface was polished and observed with an electron microscope. As shown in Figs. 2 and 3, the presence of the phosphate layer could not be confirmed from the cross-sectional observation. That is, it was confirmed that the phosphate layer formed in Example 1 was extremely thin.

(Test Example 2) Measurement of surface resistance

The insulation resistance (unit: Ω) was measured for each of the inductance elements (50 each) manufactured by the examples and the comparative examples to obtain an average value. The insulation resistance was measured by an ohmmeter with a distance between terminals of 1.5 mm on a surface having a size of 2.0 x 1.6 mm of the magnetic member. The results are shown in Table 1. As shown in Table 1, it was confirmed that the insulation resistance value was about 2.5 times different depending on the presence or absence of the inorganic insulation layer, that is, the phosphate layer.

(Test Example 3) Evaluation of "plating extension" phenomenon

The appearance of each of the inductance elements (50 each) manufactured by the examples and the comparative examples was observed, and it was confirmed whether or not the phenomenon of " plating elongation " As a result, as shown in Fig. 4, it was confirmed that the "plating extension" phenomenon (in the white circle in Fig. 4) was generated in the inductance element manufactured by the comparative example. In contrast, as shown in Fig. 5, it was not confirmed that the phenomenon of " plating extension " occurred in the inductance element manufactured by the embodiment.

(Test Example 4) Measurement of inductance

The inductance (unit: pH) at 1 MHz was measured using an impedance analyzer (" 4294A " manufactured by Ajient Corporation) for each of the inductance elements Respectively. The results are shown in Table 2. As shown in Table 1, the change of the inductance was not substantially confirmed depending on the presence or absence of the phosphate layer.

It was confirmed that the inductance element manufactured by Embodiment 1 related to the present invention has an insulating property on the surface of the magnetic member without substantially affecting the magnetic characteristics in that the insulating layer having the inorganic insulating layer is provided. As a result, the occurrence of the phenomenon of " plating elongation " was not confirmed in the inductance element of Example 1. On the other hand, in the inductance element manufactured by the comparative example 1, the phenomenon of " plating extension "

(Test Example 5) A reflow test

For each of the inductance elements (50 each) manufactured by the examples and the comparative examples, the reflow test was performed under the following conditions.

Peak temperature: 270 ° C

Peak temperature hold time: 180 seconds

After performing the reflow test once or three times, the insulation resistance was measured in the same manner as in Test Example 2 and the average value was obtained. The results are shown in Table 3 and FIG.

As shown in Table 3 and FIG. 6, the inductance of the inductance element manufactured in Example 1 did not deteriorate on the surface of the magnetic member even when the reflow test was performed. On the other hand, the inductance of the inductance element manufactured in Comparative Example 1 significantly deteriorated on the surface of the magnetic member by the reflow test. The inductance element may receive a thermal history such as a reflow in a state of being mounted on a substrate. Particularly, since the solder is melted at the time of reflow, if the mounted inductance element is small, the position of the inductance element relative to the substrate may be changed. In the case of an electronic device having a narrow mounting space such as a smart phone, if the degree of positional fluctuation of the inductance element is large, the inductance element may come into contact with the casing of the electronic appliance. Even in this state, since the inductance element of the embodiment of the present invention has a high insulation resistance of the magnetic member, an accident such as a short circuit is not generated well. In addition, since the thermal stability of the phosphate layer is high, it is expected that the environmental resistance is improved under the external environment.

In the above Examples and Comparative Examples, there is no impregnated coat layer without impregnation coating, but it is expected that the same result will be obtained even when the impregnated coat layer is formed.

INDUSTRIAL APPLICABILITY The inductance element of the present invention is preferable as a component mounted on an electronic device such as a cellular phone, a smart phone, and a notebook computer, and is particularly preferable as an inductance element used in a power supply circuit of these electronic devices.

10: Inductance element
1:
2: conductive member
2a and 2b: ends of the conductive member 2
3a, 3b: connection end

Claims

A magnetic member having a molded body containing a ferromagnetic metal powder containing Fe and an insulating layer formed on a surface portion of the molded body,
A conductive member having a portion located inside the magnetic member;
And a conductive connection end portion formed on the insulating layer of the magnetic member in a state of being electrically connected to the conductive member,
Wherein the insulating layer comprises an impregnation coat layer and a phosphate layer,
Wherein the phosphate layer is selectively formed on the ferromagnetic metal powder exposed on the surface of the molded body.

The method according to claim 1,
And the connection end portion includes a plating layer.

3. The method of claim 2,
Wherein the plating layer is formed by electroplating on a metallization layer formed on the insulating layer.

delete

4. The method according to any one of claims 1 to 3,
Wherein the magnetic member has a cavity.

An electronic device in which the inductance element according to any one of claims 1 to 3 is mounted.