JPH09270332A - Electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part capable of providing a high Q character istic owing to a high inductance and low resistance to obtain a stable inductor or transformer with greatly reduced interference between the circuit current and external magnetic field. SOLUTION: This electronic part has a ferrite substrate 11a, a laminate 15 composed of alternately laminated insulation resin layers 12a-d and conductor patterns 13a-d on the substrate 11, and external electrode terminals 24 which are electrically connected to the patterns 13a-d and run between the substrate 11 and the laminate 15. The substrate 11a and magnetic layer 2 form a closed magnetic path structure which houses at least part of the patterns 13a-d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic parts such as chip parts and lead parts, and more particularly to surface mounting of LCR elements, thin film EMI filters, common mode choke coils, signal transformers, current sensors, composite parts and the like. Electronic components such as components and lead components.

[0002]

2. Description of the Related Art Conventionally, an electronic component shown in FIG. 11 is known (see Japanese Patent Laid-Open No. 3-201417). This electronic component 100 is provided on an insulating substrate 101 such as alumina,
An insulating resin layer 102 made of a polyimide resin and internal conductor patterns 103, 104 made of Ti, Ti-Ag, Ag formed by a sputtering method are alternately laminated.
By removing the end of the insulating resin layer 102, the end of the uppermost conductor pattern 104 is exposed to expose the electronic component 1
00 is formed.

A terminal base portion is formed on a side surface of the electronic component 100 so as to be connected to an end portion of the conductor pattern 104, and the terminal base portion is covered from the upper end portion of the electronic component body through the side surface. The external electrode terminal portion reaching the lower end portion is formed and used.

[0004]

However, when the above electronic component is used for an inductor or a transformer, since the magnetic circuit generated by the current flowing through the conductor pattern is an open magnetic circuit type, it has a high inductance and a low resistance. It was difficult to obtain the resulting high Q characteristics.

Further, there is a drawback in that electromagnetic interference such as a leakage magnetic field, noise interference, and induced noise due to an external magnetic field is likely to be caused by a current flowing through the conductor pattern.

Therefore, a technical object of the present invention is to provide an electronic component which can obtain a high Q characteristic caused by a high inductance and a low resistance.

Further, another technical problem of the present invention is
An object of the present invention is to provide an electronic component that can obtain a stable inductor or transformer in which the interference between the circuit current and the external magnetic field is significantly reduced.

[0008]

According to the present invention, a substrate, a laminate formed by alternately laminating a conductor pattern and an insulating layer on the substrate, and electrically connected to the conductor pattern are provided. An electronic component including an external electrode terminal portion formed across the substrate and the laminated body, wherein the electronic component includes a closed magnetic circuit structure that accommodates at least a part of the conductor pattern. can get.

In the present invention, it is preferable to use a Cu film or an Al film as the conductor pattern.

Further, according to the present invention, in the electronic component, at least one surface of the substrate is provided with a first magnetic layer, and at least a part of the conductor pattern is covered with the second magnetic layer which is in contact with the one surface of the substrate. An electronic component comprising a layer, wherein the closed magnetic circuit structure is formed by the first magnetic layer and the second magnetic layer is obtained.

Further, according to the present invention, in the electronic component, the second magnetic layer is made of a resin film containing a magnetic substance, and the electronic component is obtained.

According to the present invention, in any one of the electronic components, the substrate is made of insulating ceramics, and the first magnetic layer is a resin film containing a magnetic substance formed on one surface of the insulating ceramics. An electronic component characterized by comprising:

Further, according to the present invention, in the electronic component, the electronic component can be obtained in which the substrate is made of a ferrite magnetic material.

In the present invention, synthetic resin such as benzocyclobutene resin and polyimide resin can be used as the material of the insulating layer, but the material is not limited to these.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an electronic component according to a first embodiment of the present invention. FIG. 2 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 1 separated from each other. 3 is a completed view of the electronic component body of FIG.

Referring to FIG. 1, an electronic component 20 according to an embodiment of the present invention shows a noise filter, which covers the electronic component main body 10 and both end surfaces and a part of side surfaces of the electronic component main body 10. External electrode terminal portion 2, which is formed on
2 and 2 are provided.

Referring also to FIG. 2 and FIG. 3, the electronic component body 1 includes the conductor pattern 1 on the ferrite substrate 11a.
3a, an insulating resin layer 12a made of benzocyclobutene resin (BCB) as an insulating layer, a magnetic layer made of a ferrite mixed resin layer 2, and an insulating resin layer 12b formed thereon.
12b, 12c and 12d and conductor patterns 13b and 1
3c and 13d are alternately laminated to obtain a laminated body 15. Through holes or notches 14 are provided in the insulating resin layers 12a to 12d. Also, instead of the conductor pattern 13c, the conductor pattern 13c
You may use '. Here, BCB is used as the insulating resin, but polyimide can be used. Furthermore, the conductor patterns 13a, 13b, 13c, 13d
Is formed by forming a Ti film or a Cr film as a base layer and superposing an electrolytic Cu plating film as a conductive film on the Ti film or Cr film in this order.

A specific method of forming the laminated body 15 is as follows. After the ferrite substrate 11a is organically cleaned, a Ti film or C on the Ti film is used as a base layer of the conductor pattern 13a.
The u film is formed by the sputtering method. Here, a Cr film may be used instead of the Ti film. Next, after coating a resist on this, it exposes through a mask using photolithography and develops to obtain a resist pattern having a desired conductor pattern as a recess. Next, an electrolytic Cu plating layer is obtained on the underlayer by electrolytic Cu plating. next,
The resist pattern is peeled off to obtain an intermediate conductor pattern, and this intermediate conductor pattern is subjected to wet etching (dry etching is also possible) to obtain an isolated conductive pattern 13a formed on the substrate.

The obtained conductor pattern 13a was composed of a base layer and an electrolytic Cu plating layer, and had a thickness of about 3 to 5 μm and a width of about 30 μm.

Next, an ultraviolet-sensitive BCB resin was applied by spin coating so as to cover the conductor pattern 13a formed on the ferrite substrate 11a to obtain an insulating resin layer. The through holes 14 were formed in the insulating resin layer 12a by exposing through a mask using photolithography. Next, the insulating resin layer 12a was obtained by heating and half-curing. Next, an epoxy resin containing ferrite powder was applied and cured, and an ultraviolet-sensitive BCB resin was applied thereon to obtain an insulating resin layer. Similar to the insulating resin layer 12a, a through hole 14 was formed in this, and it was cured by heating.

Below, conductor patterns 13b to 13 are formed on this.
d, the insulating resin layers 12c to 12d were formed by the same method as above to obtain the electronic component body 10.

Next, a conductive paste in which Ni powder is mixed with epoxy resin is applied to cover the electrode lead-out portion 21 of the electronic component body 10 shown in FIG. 3 and to cross the side surface of the ferrite substrate 11a to the lower surface. The base electrode layer 21a is formed by drying and curing, and the Ni plating film 22 and the solder plating film 23 are further formed thereon by electrolytic barrel plating, and the external electrode terminal portion 24 of the electronic component shown in FIG. 4 is formed. Are formed, and the electronic component 20 is completed.

Although the magnetic layer 2 is a resin film containing a magnetic material containing ferrite powder in a synthetic resin, any magnetic powder may be used, and the synthetic resin is ， Anything can be used. Further, instead of using the magnetic substance-containing resin film, a magnetic film such as permalloy formed by the sputtering or plating process may be used in the sputtering or plating process.

FIG. 5 is a sectional view showing an electronic component according to the second embodiment of the present invention. FIG. 6 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 5 separately. The electronic component 30 shown in FIG. 5 is different from the electronic component shown in FIG. 1 in that the substrate is an alumina substrate 11b.
And the magnetic layer 2 is further provided thereon.

The electronic parts shown in FIGS. 5 and 6 are manufactured as follows.

First, after cleaning the alumina substrate 11b organically,
An epoxy resin containing ferrite powder is applied onto this and cured to obtain the magnetic layer 1. Then, a Ti film is formed as a base layer of the conductor pattern by a sputtering method. Here, the Ti film is used as the underlayer, but a Cr film may be used. Next, after applying a resist, the resist is exposed through a mask using photolithography and developed to obtain a resist pattern having holes corresponding to the conductor patterns, and the holes are formed by electrolytic Cu plating. An electrolytic Cu plating film is obtained on the part. Furthermore, peel off the resist pattern,
Obtain an intermediate conductor pattern. Next, the Ti film in the intermediate conductor pattern is subjected to wet etching with hydrofluoric acid (dry etching is also possible) to obtain an isolated conductive pattern 13a formed on the magnetic layer 1. Next, the magnetic layer 1
The UV-sensitive BCB resin is applied by spin coating so as to cover the conductor pattern 13a formed above, and the insulating resin layer 12b is obtained. The insulating resin layer 12b is exposed through a mask using photolithography, and the insulating resin layer is exposed. A through hole 14 was formed in 12b. After curing by heating, an epoxy resin containing ferrite powder was applied on this and cured to obtain a magnetic layer 2. An insulating resin similar to that of the insulating resin layer 12b was applied thereon, and exposed through a mask using photolithography to form the through holes 14 in the insulating resin layer 12b. Next, the insulating resin layer 12b was obtained by heating and half-curing. Further, the other conductor patterns 13b, 13c, 13d in FIG. 6 can be obtained in the same manner as the above-mentioned process. Also, the insulating resin layers 12c and 12d are obtained in the same manner as the above, and when the external electrode terminal portions are formed in the same manner as in the first embodiment, they are similar to those shown in FIG. An electronic component with a unique appearance can be obtained.

FIG. 7 is a sectional view showing an electronic component according to the second embodiment of the present invention. FIG. 8 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 7 separately. The electronic component 40 shown in FIG. 5 is different from the electronic component shown in FIG. 5 in that the magnetic layer 2 is formed so as to cover the entire conductor pattern of the laminate except the electrode lead-out portion.

The electronic parts shown in FIGS. 7 and 8 are manufactured as follows.

First, after the alumina substrate 11b is washed organically,
An epoxy resin containing ferrite powder is applied onto this and cured to obtain the magnetic layer 1. Then, a Ti film is formed as a base layer of the conductor pattern. Here, the Ti film is used as the underlayer, but a Cr film may be used. Next, after applying a resist, the resist is exposed through a mask using photolithography and developed to obtain a resist pattern having holes corresponding to the conductor pattern, and this hole is formed by electrolytic Cu plating. An electrolytic Cu plating film is obtained on the part. Further, the resist pattern is peeled off to obtain an intermediate conductor pattern. Next, the Ti film in the intermediate conductor pattern was wet-etched with hydrofluoric acid (dry etching is also possible) to obtain an isolated conductive pattern 13a formed on the magnetic layer 1. Next, an ultraviolet-sensitive BCB resin is applied by spin coating so as to cover the conductor pattern 13a formed on the magnetic layer 1 to obtain an insulating resin layer, which is exposed through a mask using photolithography. Thus, the through hole 14 was formed in the insulating resin layer 12b. Similarly, the conductor patterns 13b and 13c and the insulating resin layer 12 are formed.
c, 12d were formed. After curing by heating, an epoxy resin containing ferrite powder was applied on this and cured to obtain a magnetic layer 2. An insulating resin made of UV-sensitive BCB was applied and exposed through a mask using photolithography to form an insulating resin layer. Next, the insulating resin layer 12d was obtained by heating and hardening. A conductor pattern 13d was formed thereon to serve as an electrode lead-out portion, and an electronic component body similar to that shown in FIG. 3 was obtained. If the external electrode terminal portion connected to the electrode lead-out portion is formed in the same manner as that shown in the first and second embodiments, an electronic component having an appearance similar to that shown in FIG. 4 can be obtained.

In the above-mentioned first, second, and third embodiments of the present invention, the low-pass filter having three terminals was illustrated as an electronic component, but a common mode choke coil having four terminals, a transformer, Electronic components such as a current sensor will be described below.

FIG. 9 is a perspective view schematically showing only the conductor pattern of the electronic component according to the fourth embodiment of the present invention. As shown in FIG. 9, the conductor patterns 12a to 12d shown in FIG. 2 or 3 are replaced with 13e to 13h, respectively, and cutouts or through holes are provided in the insulating layer, and the end portions of the conductor patterns and the electrode lead-out portions 25 to If the external electrode terminal portions are formed by arranging 28 to be in contact with each other, a common mode in which the pair of electrode lead-out portions 25 and 28 and the pair of electrode lead-out portions 26 and 27 serve as input / output terminal pairs, respectively. A choke coil is formed.

FIG. 10 is a perspective view schematically showing only the conductor pattern of the electronic component according to the fifth embodiment of the present invention. As shown in FIG. 10, the conductor patterns 12a to 12d shown in FIG. 2 or FIG.
Instead, a notch or a through hole is provided in the insulating layer, and the electrode lead-out portions 31 to 34 are overlapped and are in contact with each other so that the end portions of the conductor pattern and the electrode lead-out portions 25 to 28 are in contact with each other. When the external electrode terminal portion is formed, a transformer having the pair of electrode lead-out portions 31 and 32 and the pair of electrode lead-out portions 33 and 34 as an input / output terminal pair is formed.

[0034]

As described above, according to the present invention, it is possible to provide an electronic component which can obtain a high Q characteristic caused by high inductance and low resistance.

Further, according to the present invention, it is possible to provide an electronic component which can obtain a stable inductor or transformer in which the interference between the circuit current and the external magnetic field is significantly reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an electronic component according to a first embodiment of the present invention.

FIG. 2 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 1 separated from each other.

FIG. 3 is a perspective view showing a completed state of the electronic component body of FIG.

FIG. 4 is a perspective view showing the electronic component of FIG.

FIG. 5 is a sectional view showing an electronic component according to a second embodiment of the present invention.

FIG. 6 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 5 separately.

FIG. 7 is a sectional view showing an electronic component according to a third embodiment of the present invention.

8 is a perspective view schematically showing the conductor pattern and insulating layers of the electronic component body of FIG. 7 separately.

FIG. 9 is a perspective view schematically showing only a conductor pattern of an electronic component according to a fourth embodiment of the present invention.

FIG. 10 is a perspective view schematically showing only a conductor pattern of an electronic component according to a fifth embodiment of the present invention.

FIG. 11 is a sectional view showing an example of a conventional electronic component.

[Explanation of symbols]

1, 2 Magnetic Layers 10 Electronic Component Main Body 11a Ferrite Substrate 11b Alumina Substrates 12a, 12b, 12c, 12d Insulating Resin Layers 13a, 13b, 13c, 13c ', and 13d Conductor Patterns 14 Through Holes 15 Laminates 20, 30, 40 Electrons Parts 24 External electrode terminal portions 21, 22, 25, 26, 27, 28, 31, 32, 3
3,34 Electrode extraction part 100 Electronic component 101 Insulating substrate 102 Insulating resin layer 103, 104 Internal conductor pattern

Claims (5)

[Claims] 1. A substrate, a laminated body formed by alternately laminating conductor patterns and insulating layers on the substrate, and electrically connected to the conductor pattern and extending across the substrate and the laminated body. An electronic component having a formed external electrode terminal portion, wherein the electronic component has a closed magnetic circuit structure that accommodates at least a part of the conductor pattern. 2. The electronic component according to claim 1, further comprising a first magnetic layer on at least one surface of the substrate, a second magnetic layer covering at least a part of the substrate and being in contact with one surface of the substrate, An electronic component characterized in that a closed magnetic circuit structure is formed by the first magnetic layer and the second magnetic layer. 3. The electronic component according to claim 2, wherein the second magnetic layer is made of a magnetic material mixed resin film. 4. The electronic component according to claim 2 or 3, wherein the substrate is made of insulating ceramics, and
An electronic component, wherein the magnetic layer is made of a magnetic material-mixed resin film formed on one surface of the insulating ceramics. 5. The electronic component according to claim 2, wherein the substrate is made of a ferrite magnetic material.