JP2002141235A - Electronic component and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily provide an electronic component that is used in a frequency band of an nH choke coil and is available for a large current, and that is small in size and has the required characteristics. SOLUTION: This method for manufacturing an electronic component includes a step of forming a first insulation resin layer 2 on a support substrate 1, a step of uniformly forming a metal film 3 over the first insulation resin layer 2, a step of forming a photoresist film 4 by which a groove is patterned, on the metal film 3, a step of forming an inner conductor 5 on the metal film 3 in the groove of the photoresist film 4, a step of removing the photoresist film 4, a step of removing the exposed metal film 3 by etching, a step to integrally forming a second insulation resin layer 6 on the insulation resin layer 2, while covering the inner conductor 5, and a step of removing the support substrate 1 from the first insulation resin layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component and a method of manufacturing the same, and more particularly, to an electronic component having a small conductor and a high-density conductor having low resistance, and to easily form such a conductor. And a method for manufacturing an electronic component.

[0002]

2. Description of the Related Art There is an nH choke coil as an electronic component for supplying a large current in a high frequency band. Since the nH choke coil is used in a high frequency band and is supplied with a large current, it is required to have a small dielectric loss and a high withstand current. With the miniaturization of electronic devices, there is an increasing demand for miniaturization of such electronic components. Conventionally, such an electronic component is manufactured by a winding technique.
It is difficult to obtain an electronic component having a diameter of 0.5 mm or less.

[0003] In addition to manufacturing means using winding technology,
There is also a means for forming the conductor constituting the coil as a thick film conductor pattern by screen printing or the like. However, a conductor pattern formed by the thick film printing technique cannot be formed as a fine conductor pattern. In addition, since a substrate is used, the size of the substrate is increased by the volume of the substrate, which is disadvantageous for miniaturization. Therefore, there is still a limit in reducing the size of the coil component.

[0004]

As described above, as described above,
In a conventional method for manufacturing an electronic component using a winding technology or a method for manufacturing an electronic component using a thick film printing technology, nH
It is difficult to manufacture electronic components that are used in a frequency band such as a choke coil and are supplied with a large current and that are small and have required characteristics.

The present invention has been made in view of the above-mentioned problems in conventional electronic components and methods of manufacturing the same, and is an electronic component that is used in a frequency band such as an nH choke coil and through which a large current flows, and is small in size. It is an object of the present invention to easily obtain a product having various characteristics.

[0006]

In order to achieve the above-mentioned object, the present invention provides a solid small electronic component in which the internal conductor 5 is embedded in a resin. The internal conductors 5 are embedded in a resin insulator by sandwiching the insulating resin layers 2 and 6 between the insulating resin layers 2 and 6. Further, in order to manufacture such an electronic component, a support substrate 1 is used, and a first insulating resin layer 2, an internal conductor 5, and a second insulating resin layer 6 are sequentially built up thereon, and formed. Finally, the support substrate 1 is removed.

That is, the electronic component according to the present invention is characterized in that the internal conductor 5 is sandwiched between the integrated first and second insulating resin layers 2 and 6 and embedded therein. It is a feature. The internal conductor 5 embedded in the first and second insulating resin layers 2 and 6 has, for example, a coil shape.

In such an electronic component, the internal conductor 5 is sandwiched between the integrated first and second insulating resin layers 2 and 6 and embedded therein, and
Since no substrate is used for fixing the electronic component, a small electronic component can be obtained. Furthermore, since it is embedded in the insulating resin layers 2 and 6 having a relatively low dielectric constant, even if a large current flows in a high frequency band, the dielectric loss is small, and required characteristics can be obtained.

A method for manufacturing such an electronic component includes a step of forming a first insulating resin layer 2 on a support substrate 1,
Forming an internal conductor 5 on the insulating resin layer 2;
A step of integrally forming a second insulating resin layer 6 on the insulating resin layer 2 so as to cover the internal conductor 5; and a step of removing the support substrate 1 from the first insulating resin layer 2. .

The first insulating resin layer 2, the internal conductor 5, and the second insulating resin layer 6 are formed on the supporting substrate 1 in order, so that they can be easily formed.
In addition, it can be formed with high accuracy. However, finally, the support substrate 1
Is not obstructed by miniaturization.

In this method of manufacturing an electronic component, the inner conductor 5 is preferably formed by a semi-additive method. That is, the step of forming the internal conductor 5 includes a step of uniformly forming the metal film 3 on the first insulating resin layer 2,
A step of applying a photoresist film 4 on the metal film 3, exposing the photoresist film 4 in a desired pattern, and removing the exposed portions to pattern grooves in the photoresist film 4; Forming the internal conductor 4 on the metal film 3 in the groove portion, removing the photoresist film 4, and removing the exposed metal film 3 by etching.

By forming the inner conductor 5 by such a method, it is possible to form the inner conductor 5 whose height is relatively high with respect to the width. Further, it is possible to form the inner conductor 5 having a height higher than the width. Thereby, even if the inner conductor 5 has a small planar projected area, a certain cross-sectional area can be secured, and thus it is suitable for an electronic component that needs to flow a large current.

[0013]

Embodiments of the present invention will now be described specifically and in detail with reference to the drawings.
FIG. 1 is a conceptual diagram showing a manufacturing process of an electronic component according to one embodiment of the present invention.

First, as shown in FIG. 1A, a support substrate 1 is prepared. As the support substrate 1, a ceramic plate such as alumina, a glass plate such as soda glass, a metal plate such as stainless steel, and a resin sheet such as a polyethylene terephthalate sheet are used. In particular, a glass plate having a good surface smoothness is optimal.

Next, as shown in FIG. 1B, a resin material such as an epoxy resin is applied on one surface of the substrate 1,
This is cured to form the first insulating resin layer 2. Next, as shown in FIG. 1 (C), vacuum film formation, chemical plating or chemical vapor deposition (CV) is performed on the insulating resin layer 2.
D method), the metal film 3 of copper or the like is uniformly formed. The metal film 3 serves as a base for an internal conductor 5 described later.

Next, a photoresist is applied on the metal film 3 serving as a base to form a uniform photoresist film 4. A mask (not shown) having a required pattern is placed on the photoresist film 4, and parallel light is irradiated from above the mask to expose only the pattern portion of the mask. After removing the mask, the exposed portions of the photoresist film 4 are washed and removed, so that grooves are patterned in the photoresist film 4 as shown in FIG. This patterned groove has a depth-to-width ratio, that is, an aspect ratio of 0.5 or more. The initial photoresist film 4 is formed thicker, and is exposed by using a parallel light with a mask or the like as described above, and the exposed portion is washed and removed.
There is an advantage that a rectangular groove having a high aspect ratio can be easily patterned in the photoresist film 4.

A metal such as copper is grown on the patterned photoresist film 4 and on the metal film 3 by electrolytic plating or CVD to form an internal conductor 5 as shown in FIG. 1 (E). As described above, since the photoresist film 4 is patterned in the shape of a rectangular groove, a metal having a sufficient thickness is deposited on the metal film 3 to form a rectangular cross section according to the shape of the rectangular groove of the photoresist film 4. The internal conductor 5 having a high aspect ratio and having the above aspect ratio can be easily formed.

After the coil conductor 4 is formed, as shown in FIG. 1 (F), when the photoresist film 4 is removed, only the internal conductor 5 and the underlying metal film 3 remain on the substrate 1. Next, the internal conductor 5 and the metal film 3 are immersed in an etching solution,
When etching is performed by the thickness of the metal film 3, the metal film 3 is removed, and only the internal conductor 5 remains on the substrate 1 as shown in FIG. The height / width of the internal conductor 5, that is, the aspect ratio is set to 0.5 or more.

Next, as shown in FIG. 1H, an insulating resin material such as epoxy resin having fluidity is applied on the surface of the first insulating resin layer 2 so as to cover the internal conductor 5. Then, this is cured to form the second insulating resin layer 6 integrally with the first insulating resin layer 2. Thereby, the inner conductor 5
Is embedded between the integrated first insulating resin layer 2 and second insulating resin layer 6 and is insulated from the outside.

Next, as shown in FIG. 1I, the support substrate 1 is removed from the first insulating resin layer 2. For example, the support substrate 1 made of ceramic, glass or resin is peeled off from the first insulating resin layer 2, and the support substrate 1 made of metal such as aluminum is dissolved or polished with a chemical such as acid. To remove.

Such electronic parts are not individually manufactured one by one from the beginning, but usually a plurality of electronic parts are manufactured simultaneously as one. Therefore, after the support substrate 1 is removed as described above, as shown in FIG. 1J, the first insulating resin layer 2 and the second insulating resin layer 6 between the individual electronic components are separated. Cut and separate into individual electronic components. Thus, the electronic component is completed. Although FIG. 1 shows an example in which two electronic components are formed for convenience of illustration, actually, a large number of electronic components are formed vertically and horizontally on the support substrate 1 and finally cut vertically and horizontally to obtain individual electronic components. Divide into electronic components.

In such an electronic component, the internal conductor 5 is embedded in the insulating resin in which the first insulating resin layer 2 and the second insulating resin layer 6 are integrated. Inner conductor 5
Has a rectangular cross section with a height. Even if the inner conductor 5 has a small width, a required cross-sectional area can be secured, and a low-resistance inner conductor 5 can be obtained. Further, the first insulating resin layer 2 and the second insulating resin layer 6 surrounding the internal conductor 5 have a low dielectric constant and a small dielectric loss tan δ, so that the characteristics as a coil component in a high frequency band or the like are reduced. Improvement can be achieved.

FIG. 2 shows an example in which dielectric layers 7, 7 are arranged on both sides of a first insulating resin layer 2 and a second insulating resin layer 6 surrounding an internal conductor 5. FIG. 3 shows an example in which a dielectric layer 7 is arranged on one of the first insulating resin layer 2 and the second insulating resin layer 6 surrounding the internal conductor 5. .
In this case, the dielectric layer 7 may be arranged on the second insulating resin layer 6 side instead of the first insulating resin layer 2 side.

FIG. 3 shows an example in which magnetic layers 8, 8 are arranged on both sides of a first insulating resin layer 2 and a second insulating resin layer 6 surrounding an internal conductor 5. FIG. 3 shows an example in which the magnetic layer 8 is arranged on one side of the first insulating resin layer 2 of the first insulating resin layer 2 and the second insulating resin layer 6 surrounding the internal conductor 5. .
In this case, the magnetic layer 8 may be arranged on the second insulating resin layer 6 side instead of the first insulating resin layer 2 side. Thus, in order to obtain the required characteristics of the electronic component, a dielectric or a magnetic material can be arranged on both sides or one side of the first insulating resin layer 2 and the second insulating resin layer 6.

[0025]

As described above, according to the present invention, the size of the electronic component can be reduced by embedding and fixing the internal conductor 5 inside the insulating resin without using the substrate. . In addition, since the internal conductor 5 is embedded in the resin having a small dielectric constant, an electronic component having good characteristics particularly in a high frequency band can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of an electronic component from semi-finished to completed in a manufacturing process of the electronic component according to an embodiment of the present invention.

FIG. 2 is a vertical sectional side view showing an electronic component according to another embodiment of the present invention.

FIG. 3 is a longitudinal sectional side view showing an electronic component according to another embodiment of the present invention.

FIG. 4 is a vertical sectional side view showing an electronic component according to another embodiment of the present invention.

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

[Explanation of symbols]

 Reference Signs List 1 support substrate 2 metal film 3 photoresist film 4 first insulating resin layer 5 internal conductor 6 second insulating resin layer

Claims (5)

[Claims] An internal conductor embedded in a resin insulator.
The first insulating resin layer (2) and the second insulating resin layer (6) in which the internal conductor (5) is integrated.
And electronic components characterized by being embedded in them. 2. The electronic component according to claim 1, wherein the inner conductor has a height higher than a width. 3. The electronic component according to claim 1, wherein the internal conductor embedded in the resin insulator has a coil shape. 4. A method for manufacturing an electronic component having an internal conductor (5) embedded in a resin insulator, comprising: forming a first insulating resin layer (2) on a support substrate (1); Forming an internal conductor (5) on the insulating resin layer (2); and forming a second insulating resin layer (2) on the insulating resin layer (2) so as to cover the internal conductor (5). 6) A method of manufacturing an electronic component, comprising: forming a substrate; and removing the support substrate (1) from the first insulating resin layer (2). 5. The step of forming the internal conductor (5) includes a step of forming a metal film (3) uniformly on the first insulating resin layer (2) and a step of forming the metal film (3) on the first insulating resin layer (2). Coating a photoresist film (4) on the photoresist film (4), exposing the photoresist film (4) to a desired pattern, and removing the exposed portion to pattern a groove in the photoresist film (4); Metal film (2) in groove part of 3)
5. The method according to claim 4, further comprising the steps of: forming an internal conductor (4) on the substrate, removing the photoresist film (3), and removing the exposed metal film (2) by etching. A method for producing the electronic component described in the above.