JP2000021636A - Electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component of high reliability which satisfied the specification of low resistance. SOLUTION: In an electronic component 1 containing a substrate 3 and a plurality of flat coils 52a', 52b' which are laminated on the substrate in the thickness direction making insulating resin layers 51a-51d interpose, a plurality of the coils 52a', 52b' are so laminated that a coil 52b of the next layer is accommodated in a recessed part of the unevenness generated in the insulating resin layer 51b covering the coil 52a'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single element component such as an inductor (L), a capacitor (C), a resistance element (R), or a composite of an EMI filter, a common mode choke coil, a current sensor, a signal capacitance, and the like. The present invention relates to electronic components such as element components (surface mounted components, lead components).

[0002]

2. Description of the Related Art Heretofore, this type of electronic component has been known in a configuration shown in a sectional view of FIG.

In this cross-sectional view, a circuit element 5 of an electronic component 1 is formed on the surface of a substrate 3 made of an insulating material such as alumina using a photolithography technique, and has insulating resin layers 51a, 51b, 51c, 51c. 51d is made of polyimide or BCB or the like, and has conductor pattern layers 52a, 52b,
52c is formed by sputtering or plating mainly composed of Cu metal or the like.

Also, in order to form an insulating resin layer of polyimide or BCB by photolithography and a conductor pattern layer of resist, it is needless to say that the lower layer is required to be flat. Lithography becomes impossible, the shape to be formed varies,
The required shape and required characteristics are adversely affected.

When a photosensitive resin is used as the insulating resin to be the insulating resin layer, the process can be simplified. When the conductor pattern layer is formed by electroplating, it is necessary to form not only Ti--Cu, Cr--Cu, etc. as a base film by sputtering, but also to secure a required shape by etching.

After the circuit element 5 is formed by alternately laminating the insulating resin layer and the conductor pattern layer by the above method, the substrate 3 is cut into a chip shape.
The electronic component 1 is manufactured by forming an external electrode that can be electrically connected to the circuit of the circuit element 5 on the end face of the electronic component 1.

[0007]

However, when it is desired to improve the characteristics by lowering the resistance of the circuit element by about 1/2 to 1/4, the thickness of the conductor pattern of the planar coil is set to 2 to 2.
It is necessary to increase about 4 times, and as the stack is stacked with the planar coils facing up and down, the surface irregularities become remarkable, and stable photolithography cannot be performed. There is a drawback that it is difficult to manufacture a product with a problem.

[0008] Therefore, a technical object of the present invention is to provide an electronic component having high reliability and low resistance and having a sufficient specification.

[0009]

According to the present invention, there is provided an electronic component including a substrate and a plurality of planar coils stacked in a thickness direction with an insulating resin layer interposed on the substrate. An electronic component is obtained in which the planar coils are stacked such that the planar coil of the next layer is accommodated in concave and convex portions formed in the insulating resin layer covering the one planar coil.

According to the present invention, in an electronic component including a substrate and a plurality of planar coils laminated in a thickness direction with an insulating resin layer interposed on the substrate, the electronic component includes a plurality of planar coils. A conductor pattern forming a plane coil of the next layer is arranged in a concave portion of the insulating resin layer caused by the insulating resin layer entering a space between the conductor patterns forming the one plane coil. An electronic component characterized by the above is obtained.

Further, according to the present invention, the thickness of the conductor pattern constituting the planar coil is 2 to 20 μm, the width of the conductor pattern is 30 μm or less, and the width of the space is larger than the width of the conductor pattern. Thus, an electronic component characterized by the following is obtained.

[0012]

According to the above-mentioned structure, even if the thickness of the conductor pattern of the planar coil is increased by about 2 to 4 times, stable photolithography can be performed as before, and disconnection and short circuit in the electrical inspection can be prevented. In addition, it is possible to expand the specification at a low cost and with a low resistance of about 1/2 to 1/4 which is reliable.

[0013]

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

FIG. 1 is a sectional view of a main part of an electronic component according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the electronic component shown in FIG.

The substrate 3, which is a body of the electronic component 1, is made of machinable ceramics which is insulative and can be easily cut. Here, it is needless to say that a glassacea substrate or a soda lime glass or the like can be used for the substrate 3, and the cost can be further reduced.

The circuit element 5 of the electronic component 1 has a two-circuit configuration, and includes insulating resin layers 51a, 51b, 51c, 51
As for d, the conductive pattern layers 52a and 52b are formed by photosensitive BCB in which the photolithography technique is easy.
b, 52c and 52d are formed as follows. First, Ti-Cu is formed as a base film by sputtering, and then a resist is formed on the base film by a photolithography technique in a required pattern (a pattern for forming a Cu conductor pattern layer). As a mask, a required thickness of Cu is deposited on the pattern of the resist by electroplating, and then, the underlying film Cu exposed by performing the resist stripping and the Cu obtained by electroplating
The entire surface of the conductive pattern layer is etched until the underlying film Ti appears, and the exposed underlying film Ti is also etched away except for the underlying film Ti under the Cu conductive pattern layer. The above-mentioned etching process can be easily performed by a wet process, but there is no particular problem in a dry process, and it can be said that the process is safe.

Here, the conductor pattern layers 52a, 52b
Are planar coils (preferably one or more turns) of a circuit, and are not arranged in the same layer.
The conductor patterns 52a 'and 52b', which are laminated via the insulating resin layer 51b and form the planar coil of the conductor pattern layers 52a and 52b, do not face each other vertically (in the thickness direction of the conductor pattern). Lamination is carried out such that the conductor pattern of the layer above is arranged in the concave portion of the uneven shape generated in the insulating resin layer 51a sandwiched between them, and the conductor pattern of the layer thereover is arranged in the space portion (space between the conductor patterns) of the planar coil. ing.

Each of the above conductor patterns has a thickness of one.
It is about 2 μm. The pattern width of the conductor pattern is set to about 20 μm, and the space portion of the planar coil is configured to be about 24 μm, which is at least one time greater than the pattern width of the conductor pattern.

FIG. 3 is a perspective view showing an overall image of the electronic component shown in FIG.

Although not shown in the figure, since a large number of circuit elements 5 are arranged on the same substrate 3, the substrate 3 is cut corresponding to each circuit element 5 as shown in FIG. ,
By forming the external electrodes 7a, 7b, 8a, 8b on this, the electronic component 1 is completed. Here, the external electrode 7
a, 7b, 8a and 8b are formed on the conductive pattern layer 52d of the circuit element 5 and on the end face of the substrate 3 by forming an external electrode base with a conductive paste in which a metal such as Ni is mixed in a thermosetting resin;
External electrodes 7a, 7b, 9a, 9b using Ni film, solder film, etc.
It is needless to say that is formed.

FIG. 4 is an equivalent circuit diagram of the electronic component shown in FIG.

As is apparent from FIG.
The circuit configuration is configured to have at least each planar coil.

[0023]

As described above, according to the present invention, the conventional stable photolithography can be achieved even if the thickness of the conductor pattern of the planar coil is increased by about 2 to 4 times when the specification of the low resistance is expanded. An object of the present invention is to provide a low-cost and reliable electronic product that is possible, has no disconnection or short circuit in an electrical test, and has low cost and reliability.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view of the electronic component shown in FIG.

FIG. 3 is a perspective view showing an overall image of the electronic component shown in FIG.

4 is an equivalent circuit diagram of the electronic component shown in FIG.

FIG. 5 is a cross-sectional view of a main part of a conventional electronic component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic component 3 Substrate 5 Circuit element 51a Insulating resin layer 51b Insulating resin layer 51c Insulating resin layer 51d Insulating resin layer 52a Conductive pattern layer 52b Conductive pattern layer 52c Conductive pattern layer 52d Conductive pattern layer 7a External electrode 7b External electrode 9a External electrode 9b External electrode

Claims (3)

[Claims] 1. An electronic component including a substrate and a plurality of planar coils stacked in a thickness direction with an insulating resin layer interposed on the substrate, wherein the plurality of planar coils cover one planar coil. An electronic component, wherein the planar coil of the next layer is stacked in a concave portion of the unevenness generated in the insulating resin layer. 2. An electronic component comprising: a substrate; and a plurality of planar coils stacked in a thickness direction with an insulating resin layer interposed on the substrate, wherein one of the plurality of planar coils is replaced with a planar coil. A conductor pattern forming a planar coil of the next layer is disposed in a concave portion of the insulating resin layer caused by the insulating resin layer entering a space between the conductor patterns to be formed. parts. 3. The conductor pattern forming the planar coil has a thickness of 2 to 20 μm, and a width of the conductor pattern is 3 μm.
3. The electronic component according to claim 2, wherein the width of the space is set to be 0 μm or less, and the width of the space is made larger than the width of the conductor pattern.