JPH05315756A - Laminated ceramic board and manufacture thereof - Google Patents

Abstract

PURPOSE:To effectively connect a side face electrode to an inner conductor after baking even when the conductor is exposed on a surface for constituting a snap groove by exposing only a conductor having a melting point higher than a baking temperature on the groove, and disposing the conductor having a melting point lower than the baking temperature in a laminated ceramic board. CONSTITUTION:A predetermined number of green sheets GS each having larger area than that of one completed laminated ceramic board and being relatively thin are laminated, and a green sheet GS on which pastelike inner conductor L1 is printed is disposed thereon. Further, another green sheet GS is superposed thereon. This is repeated. Viaholes for connecting the conductors are formed by printing in the steps, a green sheet GS on which another inner conductor L2 is printed is disposed, and a green sheet GS is superposed thereon. And, a snap groove D is formed thereon. Here, a melting point of the conductor L1 is set lower than a baking temperature, and a melting point of the conductor L2 is set higher than the baking temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated ceramic substrate in which an internal conductor is arranged between laminated ceramics, a snap groove is formed at a predetermined position of the laminated ceramic, and the snap groove divides the laminated ceramic substrate, and a method for manufacturing the same. It is a thing.

[0002]

2. Description of the Related Art A snap method is known as one of methods for dividing a laminated ceramic substrate after firing it. Figure 3
FIG. 7 is an explanatory diagram of a conventional snap method.

First, a predetermined number of thin green sheets GS are stacked, and an internal conductor L is printed on the green sheets G.
S is placed, and another green sheet GS is placed on this.
To place. By repeating this, via holes for connecting the internal conductors are formed by printing in this process, another green sheet GS on which the internal conductors L are printed is arranged, and the green sheet GS is overlaid thereon. This state is shown in FIG. Then, as shown in FIG. 3B, a snap groove D, which is a snap groove, is formed by a snap groove forming blade B at a predetermined position of the laminated ceramic substrate thus configured. This state is shown in FIG. Then, this is fired, and after this firing, it is divided from the snap groove D, the side surface electrode SE is attached by transfer, and the internal conductor L and the side surface electrode SE are electrically connected to each other to manufacture a laminated ceramic substrate.

[0004]

By the way, the internal conductor L
It has recently been proposed that firing is performed at a temperature higher than the melting point of the conductor material constituting the above. By doing so, the internal conductor L is melted during firing, and the conductivity of the internal conductor L increases, so The electrical performance of the ceramic substrate is improved. For example, the performance of the resonator in the microwave circuit is improved.

However, in the case shown in FIG.
Of the internal conductor L, an exposed portion is generated on the surface DS forming the snap groove D. Therefore, when the internal conductor L is fired at a temperature higher than the melting point of the conductor material forming the internal conductor L, the exposed portion of FIG.
As shown in, the melted inner conductor L is ejected from the groove surface DS. As a result, the inner conductor L is not exposed from the groove surface DS, or even if the inner conductor L is exposed, the exposed area becomes very small as shown in FIG. 5, or the inner conductor L is recessed. Therefore, when the side surface electrode SE is formed on the groove surface DS, there arises a problem that contact between the inner conductor L and the side surface electrode SE is completely eliminated (broken wire) or reduced (contact failure). Further, when the melted internal conductor L is ejected from the groove surface DS during firing, the internal conductor L is divided inside the laminated ceramic substrate and the internal conductor L is divided inside the laminated ceramic substrate as shown in FIG. There is a problem that there may be a part P to be disconnected.

Disconnection between the side electrode SE and the inner conductor L,
When the contact failure occurs, when the side surface electrode SE is the ground terminal, various characteristics such as the value of Q are deteriorated in the resonator and the like, and the influence is more remarkable in the high frequency component.

According to the present invention, an internal conductor is arranged on a green sheet, another green sheet is arranged on the inner conductor, and a snap groove is formed at a predetermined position of the thus formed laminated ceramic substrate. When a laminated ceramic substrate is manufactured by firing at a temperature equal to or higher than the melting point of the internal conductor and dividing from the snap groove after the firing, even if the internal conductor L is exposed on the surface DS forming the snap groove D. The purpose is to ensure the connection between the side surface electrode and the internal conductor after firing.

[0008]

According to the present invention, an internal conductor is arranged on one green sheet, and another green sheet is arranged on the inner conductor, and a predetermined surface of a laminated ceramic substrate thus constructed. Form a snap groove at a predetermined position of
When manufacturing a laminated ceramic substrate by firing this and then dividing by a snap groove after this firing, only the conductor whose melting point is higher than the firing temperature is exposed in the snap groove, and the internal conductor whose melting point is lower than the firing temperature. Are arranged in a laminated ceramic substrate.

[0009]

According to the present invention, only the conductor having a melting point higher than the firing temperature is exposed in the snap groove, and the internal conductor having the melting point not higher than the firing temperature is arranged in the laminated ceramic substrate. Even if the conductor is exposed, after firing,
The connection between the side surface electrode and the internal conductor becomes reliable.

[0010]

FIG. 1 is a perspective view showing an embodiment of the present invention.

In this embodiment, a so-called multi-layered ceramic substrate is taken, and a predetermined number of green sheets GS each having a larger area and a relatively smaller thickness than one completed laminated ceramic substrate are stacked. Green sheet GS with paste-like internal conductor L1 printed on top
, Another green sheet GS is further laid on top of this, and this is repeated. In this process, a via hole connecting the inner conductors is formed by printing, and another green sheet GS on which another inner conductor L2 is printed is formed. The green sheet GS is placed on top of it. Then, a blade B similar to that of the conventional example is applied to this to form a snap groove D which is a snap groove. This snap groove D is for dividing the multilayer ceramic substrate by dividing the snap groove D from the snap groove D as in the conventional example, and when the snap groove D is formed,
A part of the inner conductor L2 is a groove surface D forming a snap groove D.
Exposed from S.

In the above embodiment, the melting points of the internal conductors L1 and L2 are different from each other, the melting point of the internal conductor L1 is lower than the firing temperature, and the melting point of the internal conductor L2 is set higher than the firing temperature. For example, the inner conductor L1
Is composed of a silver paste, the melting point of which is about 960 ° C., the inner conductor L2 is composed of a silver paste containing 5% by weight of palladium, the melting point of which is about 1020 ° C., and the firing temperature of 1000. It is set to ℃.

Then, the one shown in FIG. 1 is baked, divided from the snap groove D, and the side surface electrode SE is attached by transfer as shown in FIG. 2 so that the inner conductor L2 and the side surface electrode SE are formed on the groove surface DS. A laminated ceramic substrate is manufactured by electrically connecting.

In the above embodiment, the internal conductor L1 is melted during firing, but the internal conductor L2 is not melted.
The inner conductor L2 does not jet from the groove surface DS, and the inner conductor L2 does not break inside the laminated ceramic substrate. Therefore, the electrical connection between the inner conductor L2 and the side surface electrode SE is ensured.

In the above embodiment, the inner conductors are arranged on a plurality of green sheets and a plurality of the inner conductors are used. However, at least one inner sheet is arranged on the inner conductors. Another green sheet may be arranged on the substrate, and the laminated ceramic substrate may be configured in this manner.

Further, in the above embodiment, the snap groove D is provided only on the upper surface in the figure of the laminated ceramic substrate, but the snap groove D may be provided only on the lower surface, and the snap groove D is provided on both the upper surface and the lower surface. May be provided. When the snap groove D is provided on both the upper surface and the lower surface,
The snap groove D can be shallow. Furthermore, in the above-mentioned embodiment, silver paste containing 5% by weight of palladium and silver paste containing 5% by weight of palladium are used as the internal conductors L1 and L2, but copper, aluminum, gold, etc. The electrically conductive material may be used as the inner conductors L1 and L2. In short, when manufacturing a laminated ceramic substrate, only the conductor whose melting point is higher than the firing temperature is exposed in the snap groove D, and the conductor whose melting point is lower than the firing temperature is not exposed from the snap groove D. Other metals may be used as the inner conductors L1 and L2 as long as the inner conductors are arranged in the inner conductors.

The snap groove surface DS of the laminated ceramic substrate after firing and division indicates the fired surface of the ceramics, and the division surface CS divided from the snap groove D indicates the fracture surface of the ceramics. It is easy to distinguish the surface DS and the divided surface CS.

[0018]

According to the present invention, the inner conductor is arranged on the green sheet, another green sheet is arranged on the inner conductor, and the snap groove is formed at a predetermined position of the laminated ceramic substrate thus constructed. In a laminated ceramic substrate manufactured by forming, firing, and dividing from the snap groove after this firing, the side electrodes are in firm contact with the internal conductor, and the internal conductor to be melted during firing is blown out. Since this is not done, there is an effect that the electrical characteristics of the inner conductor to be melted are not impaired.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a relationship with a side electrode in the above embodiment.

FIG. 3 is an explanatory diagram of a conventional manufacturing method for a laminated ceramic substrate.

FIG. 4 is an explanatory view of a conventional laminated ceramic substrate during firing.

FIG. 5 is a perspective view showing a conventional laminated ceramic substrate.

[Explanation of symbols]

 L1, L2 ... Inner conductor, D ... Snap groove, DS ... Groove surface, GS ... Green sheet, SE ... Side electrode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoshi Hatanaka 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDC Corporation

Claims (2)

[Claims] 1. An internal conductor is arranged on one green sheet, another green sheet is arranged thereon, and a groove is formed at a predetermined position on a predetermined surface of a laminated ceramic substrate thus constructed. In the manufacturing method for manufacturing a monolithic ceramic substrate by firing this and then dividing from the groove after the firing, only the internal conductor having a melting point higher than the firing temperature is exposed in the groove, and the melting point is equal to or lower than the firing temperature. A method for manufacturing a laminated ceramic substrate, characterized in that the internal conductor is arranged in the laminated ceramic substrate. 2. A laminated ceramic substrate in which a plurality of internal conductors having different melting points are arranged between laminated ceramics, a groove is formed at a predetermined position of the laminated ceramic, and the groove is divided by the grooves. Of the internal conductor of, the internal conductor having a low melting point is exposed on the divided surface, and on the surface forming the groove,
A laminated ceramic substrate having an exposed inner conductor having a higher melting point than the inner conductor having a lower melting point.