JPH0572087B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a laminated inductor, and particularly to a method for manufacturing a terminal electrode.

[Prior art] With the demand for smaller and thinner electronic components,
In the field of inductors as well, laminated inductors that do not use windings have come into use. This laminated inductor has magnetic layers such as Ni-Zn ferrite and conductor layers such as silver formed alternately, and a spiral conductor pattern is formed by connecting between the magnetic layers, creating a closed magnetic circuit structure. It becomes an inductor.
After firing, terminal electrodes are formed on both end faces.

In order to meet the requirements for chipping, the terminal electrode 42 is formed so that both opposing end surfaces and a portion of both end surfaces of the other surface straddle each other, as shown in FIG. Further, this terminal electrode is formed by baking the ferrite and the internal conductor after firing.

〔assignment〕

However, when terminal electrodes are formed on both end faces as described above, a large stray capacitance is generated between the terminal electrodes. A capacitance of about 0.5 to 0.8 pF is generated in a laminated inductor, which causes problems such as a decrease in self-resonant frequency.

Therefore, it has been considered to form the terminal electrode only on a part of the end face, but this poses a problem in terms of strength.

The present invention forms a terminal electrode with small stray capacitance and sufficient strength.

[Means to solve the problem]

The present invention solves the above problems by forming an electrode on a part of the end face at the same time as firing.

That is, in a method for manufacturing a laminated inductor in which a conductor pattern is formed that connects and circulates between magnetic layers, both ends of the conductor pattern are drawn out to an end surface of the magnetic material, and terminal electrodes are formed on the end surface of the magnetic material, the end surface of the magnetic material is A conductor paste for forming a terminal electrode connected to the conductor pattern is applied to a part of the conductor pattern, and the terminal electrode is baked at the same time as the magnetic body and the internal conductor pattern are baked.

〔Example〕

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

FIG. 1 is a perspective view of an example of a laminated inductor manufactured according to the present invention. A ferrite magnetic paste and a silver (or silver-palladium) conductive paste are printed alternately. A conductor pattern is printed approximately half a turn at a time on the magnetic paste, with the ends connected, and a coil pattern that goes around from layer to layer is provided inside.

After a predetermined number of layers are laminated by printing, they are divided into one chip. Usually, the magnetic material 10 is fired in this state, but in the present invention, the magnetic material 10
Apply conductor paste 1 to the end surface where the conductor pattern is exposed.
2 and then bake. The conductor paste that forms this terminal electrode is different from the paste for the internal electrodes, and if the same components as the glass frit or magnetic ferrite are mixed, an electrode that is more closely bonded will be formed during firing.

It is preferable to minimize the area of the conductive paste applied to the end face of the magnetic layer. This allows the stray capacitance of the opposing terminal electrodes to be reduced. However, from the viewpoint of strength, board mounting, etc., it is better to form it so that it extends to the adjacent upper and lower surfaces.

FIG. 2 is a perspective view showing another embodiment of the present invention, in which terminal electrodes 22 are formed at opposing corner portions. In this case, the distance between the terminal electrodes becomes maximum, and the effect of reducing capacitance is significant.

In addition, as shown in FIG. 3, there are terminal electrodes 32 at the four corners.
When formed, there is no directionality, which is advantageous in terms of manufacturing and mounting.

〔effect〕

According to the present invention, since the area of the terminal electrode is small and the stray capacitance between the electrodes can be reduced,
Characteristics such as the self-resonant frequency of the laminated inductor can be improved.

In addition, since the terminal electrodes are formed at the same time as firing,
Adhesion strength can be increased. The effect can be further enhanced by using a bonding material such as glass frit.

Furthermore, since firing and baking can be performed at the same time, the number of manufacturing steps can be significantly reduced.

[Brief explanation of the drawing]

1 to 3 are perspective views showing embodiments of the present invention, and FIG. 4 is a perspective view of a conventional laminated inductor. 12, 22, 32...terminal electrode.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a laminated inductor, which comprises forming a conductor pattern that circulates while being connected between magnetic layers, drawing out both ends of the conductor pattern to an end surface of the magnetic material, and forming terminal electrodes on the end surface of the magnetic material. , a laminated layer characterized in that a conductor paste for forming a terminal electrode connected to the conductor pattern is applied to a part of the end face of the magnetic body, and the terminal electrode is baked at the same time as the magnetic body and the internal conductor pattern are fired. How to manufacture an inductor. 2. The method of manufacturing a laminated inductor according to claim 1, wherein the conductive paste for forming terminal electrodes contains glass frit. 3. The method of manufacturing a multilayer inductor according to claim 1, wherein the terminal electrode forming conductor paste contains the same ferrite as the magnetic material.