JPH09270331A - Electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part which is easy to produce, has desired characteristic which blocks water content from penetrating into inner conductor layers and has a high reliability. SOLUTION: This device has a laminate composed of alternately laminated insulation resin layers 13a-13d and conductor layers 14a-14c on an insulation substrate 11. The uppermost layer of the laminate 12 is an insulation resin layer 13d. The first conductor layer 14c, the uppermost one of the conductor layers, has a conductor pattern connected to leading electrodes 1b of the second upper layer 14b through through-holes 18 of the first resin layer 13c inserted therebetween, leading electrodes 1c, 2c of the pattern 14c are connected to those 1b, 2b of a 2nd electrode layer through second through-holes 15b, 16b of the resin layer 13c, exposed in a direction perpendicular to the laminating direction from the uppermost resin layer 13d and extend to the side face of the laminate, and the interface between leading electrodes 1c, 2c of the first pattern 14c and first resin or less 13c is sealed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electronic component,
Specifically, inductors (L), capacitors (C), electric resistance elements (R), thin film EMI filters, common mode choke coils, current sensors, signal transformers, and composite electronic parts that combine these into one part The present invention relates to surface mount components or electronic components that are lead components.

[0002]

2. Description of the Related Art Conventionally, an electronic component shown in FIG. 7 has been known (see Japanese Patent Laid-Open No. 3-201417). This electronic component includes an insulating resin layer 102 made of a polyimide resin on an insulating substrate 101 and an internal conductor pattern 1 made of Ti, Ti-Ag, Ag formed by a sputtering method.
03 and 104 are alternately laminated and the end portion of the insulating resin layer 102 is removed so that the uppermost conductor pattern 104 is formed.
The end portion of is exposed to form the electronic component 100.

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 constructed by alternately laminating the insulating resin layer and the conductor pattern on the insulating substrate, the adhesiveness of the interface between the insulating resin layer and the conductor pattern is improved. Since it was the weakest, moisture and humidity entered through the lead-out portion that was pulled out from the internal conductor pattern, changing the characteristics and significantly deteriorating the quality.

Further, although a plating step is usually required to provide the external electrode terminals, there is a risk that the plating solution may enter during the plating to corrode the conductor pattern.

Therefore, it may be possible to seal the exposed interface of the electronic component with a metal layer, but this leads to an increase in the number of steps and an increase in cost.

Therefore, a technical object of the present invention is to provide a highly reliable electronic component which is easy to manufacture and has desired characteristics.

[0008]

According to the present invention, an insulating substrate, a laminate in which a plurality of insulating resin layers and a plurality of conductor layers are alternately laminated on the insulating substrate, and a conductor in the conductor layer In the electronic component, which is connected to the extraction electrode portion of the pattern and has an external electrode terminal portion formed from the side surface of the laminated body to the side surface of the insulating substrate, one of the uppermost layers of the laminated body is an insulating material. A conductor pattern in the first conductor layer, which is a resin layer and is the first from the upper layers of the plurality of conductor layers,
The first conductor is connected to the lead electrode portion of the conductor pattern in the second conductor layer which is the second layer from the upper layer, through the first through hole provided in the insulating resin layer interposed therebetween. The lead electrode portion of the layer is connected to the lead electrode portion of the second conductor layer through a second through hole provided in the insulating resin layer interposed between the first and second conductor layers. The lead-out electrode portion of the first conductor layer is exposed from the uppermost insulating resin layer in a direction perpendicular to the stacking direction and extends to the side surface of the stack. An electronic component that operates is obtained.

Further, according to the present invention, at least one of the insulating resin layers may be substantially composed of benzocyclobutene.

The conductor layer may be composed of a base layer made of a conductive metal film and a Cu plating film formed on the base layer by electrolytic plating.

Furthermore, the underlayer may be composed of a Ti or Cr film formed by sputtering.

[0012]

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

FIG. 1 is a partial cross-sectional view showing an essential part of an electronic component according to an embodiment of the present invention. As shown in FIG. 1, the electronic component includes an electronic component body 10. The electronic component body 10 includes an insulating substrate 11 and a laminated body 12 formed on the insulating substrate 11. Laminate 12
The insulating resin layers 13a, 13b, 13c, 13d and the conductor layers 14a, 14b, 14c are alternately laminated.

Each of the conductor layers has lead electrode portions 1a, 1b, 1c, and
2a, 2b, 2c are provided.

The lead electrode portions 1a, 1b, 1c are connected to each other through the through holes 15a, 15b, and the lead electrodes 2a, 2b, 2c are connected to the through holes 16a, 1c.
They are connected to each other via 6b.

The conductor pattern of the first conductor layer 14c from the top is connected to the second lead electrode 1b from the top through a through hole 18 provided in the insulating resin layer 13c between them.

The lead-out electrode portion 1c and the lead-out electrode portion 2c are provided with the laminated body 12 through the notches 15c and 16c.
Has reached the side.

With this structure, the interface between the lead electrode portions 1c and 2c of the first conductor pattern 14c and the first insulating resin layer 13c is the uppermost insulating resin layer 13d and the first conductor pattern 14c itself. Since it is sealed with
Permeation of water or plating solution from the outside is effectively prevented.

As the insulating substrate, it is preferable to use a ceramic having a good free-cutting property. In addition, the insulating resin layers 13a, 13
For b, 13c, and 13d, an ultraviolet-sensitive benzocyclobutene resin (BCB) is used.

2 to 4 are schematic views showing a method of forming each insulating resin layer and each conductor layer in FIG.

Referring to FIG. 2, a ceramic substrate (not shown) is washed with acetone, methanol, or the like, and if necessary, reverse sputtering is performed to wash it, and then, as shown in FIG. Then, the underlying pattern layer 3 made of a Ti film and a Cu film formed thereon is formed by sputtering by sputtering. FIG. 2B shows the insulating resin layer 13a on which the underlayer 21 is formed. In FIG. 2B, T
The i film has a thickness of 0.05 μm, and the Cu film has a thickness of 0.25 to 0.25.
0.3 μm.

By using BCB as the insulating resin layer, the flatness of the insulating resin layer is ensured well, so that it is possible to obtain a laminate having a flat surface without irregularities.
Good electrical characteristics.

Next, as shown in FIG. 2C, the resist 2
2 is applied, then, as shown in FIG. 2D, it is exposed through a mask 23 using photolithography and developed to obtain a resist pattern 22 'shown in FIG. 3A.

Next, as shown in FIG. 3 (a), H ₂ SO ₄
After surface treatment with Cu, as shown in FIG.
The electrolytic Cu plating layer 24 is obtained by plating.

Next, the resist pattern 22 'is peeled off to obtain an intermediate conductor pattern 25 having the shape shown in FIG. 3 (c).

Next, the intermediate conductor pattern 25 shown in FIG. 3C is subjected to wet etching (or dry etching is possible) to remove the portion of the underlayer 21 exposed between the electrolytic Cu plating layers 24. And then washed with HCl, as shown in FIG.
As shown in (d), an isolated pattern 14a formed on the insulating resin layer 13a is obtained. In addition, by etching,
Although the upper surface of the electrolytic Cu plating layer 24 is also slightly etched, since it is thicker than the base plating layer 21, the conductor pattern is not lost.

The conductor layer 14a thus obtained is composed of the pattern of the underlayer 21 and the pattern of the electrolytic Cu plating layer 24 and has a thickness of about 3 to 5 μm and a width of about 30 μm, and is subjected to cleaning, photolithography, etching and cleaning steps. No problems occurred during the manufacturing process.

FIG. 4 is a diagram schematically showing a method for forming a resin insulating layer. Referring to FIG. 4, as shown in FIG. 4A, the UV-sensitive BCB resin is spin-coated so as to cover the conductor layer 14a formed on the insulating layer 13a shown in FIG. 3D. The coating is applied to obtain the insulating resin layer 26. Next, as shown in FIG. 4B, photolithography is used to perform exposure through the mask 27, and then, as shown in FIG.
As shown in (c), the through hole 18 is formed in the insulating resin layer 26. It is needless to say that the through hole 18 is not required to be provided on all the conductor patterns 14a because it is for obtaining electrical contact with the conductor formed on the insulating resin layer 26.

Next, by half-curing at 210 ° C. for 30 minutes in a nitrogen atmosphere, the insulating resin layer 1 shown in FIG.
You get 3b.

By repeating the above steps, FIG.
A plurality of electronic component bodies shown in (1) are connected vertically and horizontally by a ceramic substrate.

Further, another conductor pattern 14 in FIG.
b, 14c and 14d are also obtained in the same manner as the steps shown in FIGS. Also, the insulating resin layers 13b, 13c, 1
3d is also obtained in the same manner as the step shown in FIG.

Next, the process of forming the external electrode terminal portion on the electronic component body 1 will be described with reference to FIG.

Referring to FIG. 5, the extraction electrode portion 1c is exposed at the end of the upper surface of the electronic component body 10 shown in FIG. A Ni conductive paste 5 made of epoxy resin or the like containing Ni powder was applied to the side surfaces of the insulating substrate 11 and the laminated body 12 so as to be connected to the lead electrode portion 1c, and was thermally cured. Next, by electrolytic barrel plating, Ni
The plating film was formed on the conductive paste cured product as the base layer 6a. Here, Ni is excellent in electrolytic migration and prevents solder or the like from diffusing into the drawer.
Next, on the base layer 6a, a solder plating film 6b was formed as an external connection film by electrolytic barrel plating from a solder bath.

FIG. 6 is a perspective view showing an electronic component formed from the electronic component body of FIG.

Examples of the electronic component of the present invention include a low-pass filter and an LCR circuit element having a three-terminal structure having external electrode terminal portions 6 at both ends and side surface center portions.

[0036]

As described above, according to the present invention, the structure is simple, the manufacturing is easy, and the desired characteristics are obtained in which moisture and plating solution are prevented from penetrating from the outside. A highly reliable electronic component can be provided.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an electronic component body of an electronic component according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically showing a method for forming a conductor layer in FIG.

FIG. 3 is a cross-sectional view schematically showing a step of forming a conductor layer following that of FIG.

FIG. 4 is a cross-sectional view schematically showing a method of forming an insulating resin layer on a conductor layer.

5 is a partial cross-sectional view showing an external electrode terminal portion of the electronic component of FIG.

6 is a perspective view showing an electronic component having the external electrode terminal portion of FIG.

FIG. 7 is a partial cross-sectional view showing an example of a conventional electronic component.

[Explanation of symbols]

6 External Electrode Terminal 6a Underlayer 6b External Connection Film 10 Electronic Component Main Body 11 Insulating Substrate 13a, 13b, 13c, 13d, 13e Insulating Resin Layer 14a, 14b, 14c, 14d, Conductor Layer 15a, 15b, 16a, 16b, 18 Penetration Hole 21 Underlayer 22 Resist 23 Mask 22 'Resist pattern 24 Electrolytic Cu plating layer 25 Intermediate conductor pattern 26 Insulating resin layer

Claims (4)

[Claims] 1. An insulating substrate, and a laminate in which a plurality of insulating resin layers and a plurality of conductor layers are alternately laminated on the insulating substrate,
In the electronic component, which is connected to the lead-out electrode portion of the conductor pattern in the conductor layer and has an external electrode terminal portion formed from the side surface of the laminated body to the side surface of the insulating substrate, The upper layer is an insulating resin layer, and the conductor pattern in the first conductor layer which is the first layer from the upper layers of the plurality of conductor layers is the conductor in the second conductor layer which is the second layer from the upper layer. The lead-out electrode portion of the first conductor layer is connected to the lead-out electrode portion of the pattern through a first through hole provided in the insulating resin layer interposed therebetween. The lead electrode portion is provided with the first and second
Connected via a second through hole provided in an insulating resin layer interposed between the conductor layers of the first conductive layer, the lead electrode portion of the first conductive layer is laminated from the uppermost insulating resin layer. An electronic component, which is exposed in a direction perpendicular to the direction and extends to the side surface of the laminate. 2. The electronic component according to claim 1, wherein at least one of the insulating resin layers is substantially made of benzocyclobutene. 3. The electronic component according to claim 1, wherein the conductor layer is a base layer made of a conductive metal film and a Cu plating film formed on the base layer by electrolytic plating. An electronic component characterized by being present. 4. The electronic component according to claim 3, wherein the underlayer is made of a Ti or Cr film formed by sputtering.