JPH09270656A - Noise absorber - Google Patents

Abstract

(57) Abstract: A noise absorbing element having an easy manufacturing process and reduced defects in the internal structure is provided. SOLUTION: A zigzag-shaped electrode 12 and a comb-shaped electrode 13 are formed on a magnetic substrate 11 by using a thick film printing method, and further, the zigzag-shaped electrode 12 and the comb-shaped electrode 13 are formed by a thick film printing method. The dielectric layer 14 was formed so as to cover the sandwiched space.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a noise absorbing element.

[0002]

2. Description of the Related Art Conventionally, an LC integrated chip type noise filter manufactured by a green sheet laminating method has been known. This noise filter is manufactured by, for example, laminating an inductance element using ferrite and a capacitor element using a dielectric. Alternatively, a chip is formed by mixing a dielectric substance and a magnetic substance,
A noise filter manufactured by forming an electrode on the chip and integrally firing the chip and the electrode is also considered.

[0003]

However, in manufacturing the above-described noise filter, an inductance element using ferrite and a capacitor element using a dielectric are bonded to each other or a dielectric and a magnetic material are mixed. Therefore, there is a problem in that the manufacturing of the noise filter is complicated. Further, since the above-mentioned noise filters are all manufactured using the dielectric green sheet laminating method, not only the noise filter is complicated to manufacture, but also the electrode and the green sheet are integrally fired. There is also a problem in that defects in the internal structure such as delamination are likely to occur.

In view of the above circumstances, it is an object of the present invention to provide a noise absorbing element which is easy to manufacture and has a reduced number of defects in its internal structure.

[0005]

A noise absorbing element of the present invention that achieves the above object extends at least a predetermined distance from each other on the same plane on a substrate whose surface is formed of a magnetic material. A first electrode having an inductor component present,
And a second electrode having a capacitor component between the first electrode and the first electrode is formed by a screen printing method.

Here, the second electrode is a comb-shaped electrode having a plurality of tooth shapes, and the first electrode is a serpentine electrode extending along the plurality of tooth shapes of the second electrode. Is effective. It is also preferable that a dielectric layer is further formed by a thick film method on the substrate on which the first electrode and the second electrode are formed.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a plan view (a) of a noise absorbing element according to the first embodiment of the present invention and AA ′ of the noise absorbing element.
It is a sectional view (b) and an equivalent circuit diagram (c) of the noise absorbing element.

The noise absorbing element 10 shown in FIG.
The magnetic substrate 11 includes a zigzag-shaped electrode 12, a comb-shaped electrode 13 having three teeth, and a dielectric layer 14. A comb-shaped electrode 13 and a zigzag-shaped electrode 12 facing the three teeth of the comb-shaped electrode 13 are formed on the surface of the magnetic substrate 11 of the noise absorbing element 10 by a thick film printing method. . Further, as shown in FIGS. 1A and 1B, a space portion sandwiched between the zigzag folded electrode 12 and the comb-shaped electrode 13, a portion other than both ends of the zigzag folded electrode 12, and teeth of the comb-shaped electrode 13 are formed. A dielectric layer 14 is formed by a thick film printing method so as to cover the portions. The portions of the zigzag-shaped electrode 12 not covered with the dielectric layer 14 are the first terminal electrode 12a and the second terminal electrode 12b, and the comb-shaped electrode 13 is covered with the dielectric layer 14. The non-existing portion is the terminal electrode 13a.

The noise absorbing element 10 is used, for example, while being grounded, and an inductance is obtained from the magnetic substrate 11 and the zigzag electrode 12 formed on the surface of the magnetic substrate 11, and the zigzag electrode 12 and the comb-shaped electrode are provided. The capacitance is obtained from 13 and. Further, the inductance value can be adjusted by adjusting the length, width, thickness, etc. of the zigzag-shaped electrode 12 formed on the surface of the magnetic substrate 11, and the comb-shaped electrode 13 of the zigzag-shaped electrode 12 can be adjusted.
By adjusting the length of the portion facing the zigzag-shaped electrode 12, the distance between the teeth of the zigzag electrode 12 and the teeth of the comb-shaped electrode 13, the dielectric constant of the magnetic substrate 11, the dielectric constant of the dielectric layer 14, and the like. You can adjust the value.

The dielectric layer 14 is formed on the dielectric layer 14.
A larger capacitance can be obtained by printing a conductor having a smaller area and firing it to form a float electrode. Further, by forming an overcoat glass layer on the uppermost printed layer of the noise absorbing element 10,
It is possible to suppress changes in the characteristics of the noise absorbing element 10 that occur when performing various reliability tests on the noise absorbing element 10.

Although the noise absorbing element 10 is manufactured by using a magnetic substrate, a magnetic layer is formed on a substrate other than the magnetic substrate by a thick film printing method, and the magnetic layer is formed on the magnetic layer. The noise absorbing element may be manufactured by forming electrodes. FIG.
In the equivalent circuit shown in (c), one end of the inductance element 15 is connected to one end of the capacitor element 16, the other end of the capacitor element 16 is grounded, and the other end of the inductance element 15 serves as a terminal 17, In this circuit, the connection point between 15 and the capacitor element 16 is the terminal 18.

The inductance element 15 is the magnetic substrate 1.
1 and a zigzag-shaped electrode 12 formed on the surface of the magnetic substrate 11, and the capacitor element 16 is formed of the zigzag-shaped electrode 12 and the comb-shaped electrode 13. This equivalent circuit is a circuit in which the inductance element 15 and the capacitor element 16 are connected in a T type, and is therefore called a T type LC circuit.

In the noise absorbing element 10, the magnetic substrate 11 is used.
Since the zigzag-shaped electrode 12 and the comb-shaped electrode 13 are simultaneously formed on the surface of the film by the thick film printing method, the inductance element and the capacitor element are bonded to each other to manufacture the noise filter by using the green sheet lamination method. Also, the manufacturing process can be greatly simplified. Further, in the thick film printing method, since firing is performed each time the thick film layer is printed, structural defects such as delamination, which are found in a noise filter manufactured using the green sheet laminating method, do not occur.

FIG. 2 is a plan view (a) of a noise absorbing element according to the second embodiment of the present invention and A- of the noise absorbing element.
FIG. 3A is a sectional view taken along the line A ′ and FIG. 7C is an equivalent circuit diagram of the noise absorbing element. The noise absorbing element 20 shown in FIG.
Includes a magnetic substrate 21, a serpentine electrode 22, a comb-shaped electrode 23 having two teeth, and a dielectric layer 24. A comb-shaped electrode 23 and a zigzag-shaped electrode 22 facing two teeth of the comb-shaped electrode 23 are formed on the surface of the magnetic substrate 21 of the noise absorbing element 20 by a thick film printing method. . 2 (a) and 2 (b)
As shown in FIG. 3, the dielectric layer 24 is formed so as to cover the space portion sandwiched between the zigzag-shaped electrode 22 and the comb-shaped electrode 23, the portion other than both ends of the zigzag-shaped electrode 22, and the tooth portion of the comb-shaped electrode 23. It is formed by a thick film printing method. The portions of the zigzag folded electrode 22 not covered with the dielectric layer 24 are the first terminal electrode 22a and the second terminal electrode 22b.
The portion of the comb-shaped electrode 23 not covered with the dielectric layer 24 is the terminal electrode 23a. Also,
The equivalent circuit shown in FIG. 2C can be shown by an equivalent circuit similar to the equivalent circuit shown in FIG. A noise absorbing element may be formed by using the zigzag-shaped electrode 22 and the comb-shaped electrode 23.

FIG. 3 is a plan view (a) of a noise absorbing element according to the third embodiment of the present invention and A- of the noise absorbing element.
FIG. 3A is a sectional view taken along the line A ′ and FIG. 7C is an equivalent circuit diagram of the noise absorbing element. The noise absorbing element 30 shown in FIG.
Includes a magnetic substrate 31, a zigzag-shaped electrode 32, a comb-shaped electrode 33 having two teeth, and a dielectric layer 34. On the surface of the magnetic substrate 31 of the noise absorbing element 30, a comb-shaped electrode 33 and a zigzag-shaped electrode 32 facing two teeth of the comb-shaped electrode 33 are formed by a thick film printing method. . 3 (a) and 3 (b)
As shown in FIG. 3, the dielectric layer 34 is formed so as to cover the space portion sandwiched between the zigzag-shaped electrode 32 and the comb-shaped electrode 33, the portion other than both ends of the zigzag-shaped electrode 32, and the tooth portion of the comb-shaped electrode 33. It is formed by a thick film printing method. The portions of the zigzag folded electrode 32 not covered with the dielectric layer 34 are the first terminal electrode 32a and the second terminal electrode 32b.
The portion of the comb-shaped electrode 33 not covered with the dielectric layer 34 serves as the terminal electrode 33a. Also,
The equivalent circuit shown in FIG. 3C can be represented by an equivalent circuit similar to the equivalent circuits shown in FIGS. 1C and 2C. You may form a noise absorption element using such a zigzag-shaped electrode 32 and the comb-shaped electrode 33.

[0016]

Embodiments of the present invention will be described below.
4 to 6 are plan views (a) and AA 'sectional views (b) showing manufacturing steps 1 to 3 of the noise absorbing element according to the first embodiment of the present invention. First, the Ni-Cu-Zn ferrite substrate 41 shown in FIG. 4 was manufactured by using the extrusion method.

Next, the Ni-Cu-Zn ferrite substrate 4
1 has a zigzag pattern Ag shown in FIG.
The / Pd electrode and the comb-shaped Ag / Pd electrode are simultaneously printed using a screen printing method and dried, and then 8
Firing was performed in a belt furnace set at a temperature of 50 ° C. to obtain a zigzag folding electrode 42 and a comb-shaped electrode 43. Next, in order to obtain a large capacitance, the zigzag electrode 42 and the comb-shaped electrode 4
The dielectric constant ε≈ of a rectangular pattern as shown in FIG. 6 is formed so as to cover the space portion sandwiched by 3 and the portion other than both ends of the zigzag-shaped electrode 42 and the tooth portion of the comb-shaped electrode 43.
The dielectric layer 44 was obtained by printing 2000 dielectric pastes, drying and firing. In this way, the portions of the zigzag-shaped electrode 42 not covered with the dielectric layer 44 become the first terminal electrode 42a and the second terminal electrode 42b, and are covered with the dielectric layer 44 of the comb-shaped electrode 43. But not the part
The noise absorbing element 40 to be the third terminal electrode 43a was manufactured.

In the noise absorbing element 40 manufactured as described above, the third terminal electrode 43a and the first terminal electrode 4 are
The capacitance between the second terminal electrode 42a and the second terminal electrode 42a was 183 pF, and the inductance between the first terminal electrode 42a and the second terminal electrode 42b was 0.78 μH. In the film thickness printing method used when manufacturing the noise absorbing element 40 described above, screen printing was performed under the condition that the emulsion thickness was 20 μm and 325 mesh stainless steel was used. The printing machine was used under the conditions that the snap-off was 1.0 mm, the printing pressure was 2 kg, and the sword squeegee was used. Drying was performed using a belt furnace type drying furnace at a temperature of 150 ° C. for 15 minutes. Firing is carried out in air using a belt-type firing furnace at 850 ° C to 9 ° C.
It was carried out at a temperature of 00 ° C. for 1 hour.

Here, in manufacturing the noise absorbing element 40, since the zigzag-shaped electrode 42 and the comb-shaped electrode 43 are simultaneously formed on the surface of the magnetic substrate 41 by the thick film printing method, the green sheet lamination method is used. The manufacturing process is greatly simplified as compared with the case where the noise element is manufactured by bonding the inductance element and the capacitor element together. In addition, since the firing is performed every time the thick film layer is printed, structural defects such as delamination, which are found in a noise filter manufactured by using the green sheet laminating method, do not occur.

7 to 11 are views showing manufacturing steps 1 to 5 of the noise absorbing element of the second embodiment of the present invention. 7 to 1
(A) shown in FIG. 0 is a plan view, (b) is its AA ′ cross-sectional view, (a) shown in FIG. 11 is a plan view, and (b) is a side view thereof. First, as shown in FIG. 7A, a ferrite layer 72 was formed on an alumina substrate 71 having a scribing groove for chip division shown in FIG. 7B using a Ni—Cu—Zn ferrite paste.

Next, as shown in FIG. 8, a zigzag pattern Ag electrode and a comb-shaped Ag electrode are simultaneously printed on the ferrite layer 72 by a screen printing method to form a zigzag electrode 73 and a comb-shaped pattern. Electrodes 74 and
Next, as shown in FIG. 9, a dielectric paste having a dielectric constant ε≈2000 is filled with a space between the zigzag-shaped electrode 73 and the comb-shaped electrode 74, a part other than both ends of the zigzag-shaped electrode 73, and the comb-shaped electrode 74. The dielectric layer 75 was obtained by printing so as to cover the tooth portion of the.

Next, as shown in FIG. 10, an overcoat layer 76 made of amorphous glass is formed on the surface of the dielectric layer 75 in order to prevent a change in the characteristics of the noise absorbing element that occurs during a moisture resistance test or the like. It was formed and baked at a temperature of 600 ° C. for 1 hour. Next, it was divided along the scribe groove of the alumina substrate into chips. Next, as shown in FIG. 11, Ag is formed so as to cover the exposed portion of the zigzag folded electrode 73.
Forming the first terminal electrode 77 and the second terminal electrode 78 of
The ground electrode 79 covers the exposed portion of the comb-shaped electrode 74.
Was formed and baked at a temperature of 580 ° C. and then plated to obtain a noise absorbing element 70 (T-type LC chip filter).

In the noise absorbing element 70 manufactured as described above, the first terminal electrode 77 and the ground electrode 79 are provided.
The electrostatic capacitance between the first terminal electrode 77 and the second terminal electrode 78 is 171 pF, and the inductance between the first terminal electrode 77 and the second terminal electrode 78 is
It was 0.52 μH. Further, the screen printing conditions, the printing press conditions, the drying conditions, and the firing conditions in the above-described thick film printing method are the same as the conditions used when manufacturing the noise absorbing element 40 described above.

Here, in manufacturing the noise absorbing element 70, a ferrite layer 72 is formed on an alumina substrate 71 using a paste of Ni-Cu-Zn ferrite, and a thick film printing method is used on the surface thereof. Since the zigzag folded electrode 73 and the comb-shaped electrode 74 are formed at the same time, the manufacturing process is much simplified compared to the case where the noise filter is manufactured by bonding the inductance element and the capacitor element using the green sheet lamination method. . In addition, since the firing is performed every time the thick film layer is printed, structural defects such as delamination, which are found in a noise filter manufactured by using the green sheet laminating method, do not occur.

In the noise absorbing element of this embodiment, the noise absorbing element may be manufactured by forming electrodes on a magnetic substrate, or a thick film printing method on a substrate other than the magnetic substrate. It may be manufactured by forming an electrode on the magnetic layer formed by using. The element structure may be a chip element or a constituent circuit of a thick film circuit board.

[0026]

As described above, according to the noise absorbing element of the present invention, it is possible to obtain the noise absorbing element in which the manufacturing process is easy and the internal structural defects are reduced.

[Brief description of drawings]

FIG. 1 is a plan view (a) of a noise absorbing element according to a first embodiment of the present invention, an AA ′ sectional view of the noise absorbing element (b), and an equivalent circuit diagram of the noise absorbing element (c). Is.

FIG. 2 is a plan view (a) of the noise absorbing element according to the second embodiment of the present invention, an AA ′ sectional view of the noise absorbing element (b), and an equivalent circuit diagram of the noise absorbing element (c). Is.

FIG. 3 is a plan view (a) of a noise absorbing element according to a third embodiment of the present invention, an AA ′ sectional view of the noise absorbing element (b), and an equivalent circuit diagram of the noise absorbing element (c). Is.

FIG. 4 is a plan view (a) and a sectional view taken along the line AA ′ (b) showing a manufacturing step 1 of the noise absorbing element according to the first embodiment of the present invention.

5A and 5B are a plan view and a sectional view taken along the line AA ′ showing the manufacturing process 2 of the noise absorbing element according to the first exemplary embodiment of the present invention.

FIG. 6 is a plan view (a) and a sectional view taken along the line AA ′ of the manufacturing step 3 of the noise absorbing element according to the first embodiment of the present invention.

FIG. 7 is a plan view (a) and a sectional view taken along the line AA ′ (b) showing a manufacturing step 1 of the noise absorbing element according to the second embodiment of the present invention.

8A and 8B are a plan view and a sectional view taken along the line AA ′ showing the manufacturing process 2 of the noise absorbing element according to the second embodiment of the present invention.

FIG. 9 is a plan view (a) showing the manufacturing step 3 of the noise absorbing element according to the second embodiment of the present invention and an AA ′ cross-sectional view thereof (b).

FIG. 10 is a plan view (a) showing the manufacturing step 4 of the noise absorbing element according to the second embodiment of the present invention and a sectional view (b) taken along the line AA ′.

FIG. 11 is a plan view (a) and a side view showing a manufacturing step 5 of the noise absorbing element in the second example of the present invention.

[Explanation of symbols]

10, 20, 30, 40, 70 Noise absorption element 11, 21, 31, 41, 71 Substrate 12, 22, 32, 42, 73 Zigzag-shaped electrode 13, 23, 33, 43, 74 Comb-shaped electrode 12a, 12b, 13a , 22a, 22b, 23a, 3
2a, 32b, 33a, 42a, 42b, 43a, 7
7,78 Terminal electrode 14,24,34,44,75 Dielectric layer 15 Inductance element 16 Capacitor element 15,16 Terminal 72 Ferrite layer 76 Overcoat layer

Claims (3)

[Claims] 1. A first electrode having an inductor component, which extends on the same plane on a substrate, at least the surface of which is formed of a magnetic material, at a predetermined interval between each other, and the first electrode. A noise absorbing element, characterized in that a second electrode having a capacitor component between the electrode and the electrode is formed by a screen printing method. 2. The second electrode is a comb-shaped electrode having a plurality of tooth shapes, and the first electrode is a serpentine electrode extending along the plurality of tooth shapes of the second electrode. The noise absorbing element according to claim 1, wherein 3. The dielectric layer is further formed by a thick film method on the substrate on which the first electrode and the second electrode are formed, and the dielectric layer is formed. Noise absorbing element.