JPH01218093A - Thick film multilayer circuit board - Google Patents

Abstract

PURPOSE:To avoid rising of chip components by causing a surface on which the chip components are connected with their conductors to be higher than a multilayer circuit having either a region interposed between the connecting terminals of the chip components or an insulator. CONSTITUTION:A first conductor 2 and an insulator 3, 3' are printed and baked on an insulating board 1 and a conductor 2, respectively. A second conductor 4 is printed and baked so that it is connected to the conductor 2 through a via hole 7. A soldering paste is printed on a thick film multilayer board and is reflow-soldered by heating after a chip 6 has been mounted. The surface of the second conductor 4 to be soldered, i.e., the bottom surface of terminal electrodes 6a, 6b, protrudes compared to the surface of the insulator 3, so that contact between the bottom 6c of a component 6 and the top surface of an insulating section 3' can be avoided. Accordingly, it is possible to avoid rising of the component 6 due to contact of the bottom 6c of the component 6 with the insulating section 3' which is present between the electrodes of the component 6.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a thick film multilayer circuit board, and in particular, the surface mounting is
The present invention relates to a thick film multilayer circuit board suitable for one connection.

(Prior Art) An example of a conventional thick film multilayer circuit board is shown in FIG. In the figure, 1 is a ceramic substrate, 2 is the ceramic substrate 1
A first conductor is formed on the first conductor, 3 and 3° are insulators formed on the first conductor, 5 is solder, and 6 is a chip component that is circularly piped onto the first conductor 2 by the solder 5. .

In the conventional JV film multilayer circuit board with the above configuration, care must be taken to insulate the crossover portion of the conductor and prevent disconnection, or when soldering, to improve the reliability of the connection by changing the amount of solder on the parts. It has been.

As a publicly known publication related to the above-mentioned prior art, Japanese Patent Publication No. 5
Publication No. 7-5 6 7 9 7, JP 60-3409
6, JP-A No. 62-86792, and the like.

(Problems to be Solved by the Invention) The above-mentioned prior art is based on 'F. No consideration was given to the number of laminated layers under the terminal electrodes 5a, 5b for the connecting parts, such as the chip parts 6, and the number of laminated insulating parts in the area sandwiched between the terminal electrodes. Therefore, as shown in Figure 3,
If the number of laminated layers in the do portions of the terminal electrodes 6a, 6b is smaller than the number of laminated layers in the area sandwiched between the terminals, the bottom 6C of the chip component 6 will come into contact with the insulating part 3' in the area during solder connection. However, there is a problem in that the chip component 6 is no longer kept horizontal and is tilted, causing a phenomenon in which the component rises (referred to as a tombstone phenomenon or Manhattan phenomenon), resulting in poor connection.

An object of the present invention is to eliminate the problems of the prior art described above, reduce connection failures due to the rising phenomenon of parts caused by parts not being kept horizontal, and improve reliability. .

(Means for Solving the Problem) In order to achieve the above object, the number of laminated layers of the lower structure of the terminal electrode for a half-eleventh; The soldering is characterized in that the number of layers is the same as or greater than the number of layers of the multilayer circuit in the area sandwiched, and the bottom surface of the soldering component is higher than the multilayer circuit in the area sandwiched by the terminal electrodes. be.

(Function) In the present invention, the number of laminated layers of the lower structure of the terminal electrode for the connecting component is equal to or more than the same number of layers as the multilayer circuit in the d1 area sandwiched between the terminal electrodes, so the soldering is performed on the connecting component. Contact between the bottom of the insulator and the top of the insulator can be avoided, thereby
Since the relevant component is kept horizontal with respect to the connection surface, the phenomenon of the component lifting up does not occur, and connection failures can be avoided.

(Example) An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a sectional view of essential parts of a thick film multilayer circuit board according to the present invention. In the figure, 4 indicates a second conductor electrically connected to the first conductor 2, 7 indicates a pier hole on the first conductor 2, and other symbols are the same as or equivalent to those in FIG. 3.

In this example, a first conductor 2 is printed and fired on an insulating substrate 1 made of ceramic or the like, an insulator 3,3° having a pier hole 7 is printed and fired on the first conductor 2, and then Second
The conductor 4 is formed by printing and firing so as to be connected to the first conductor 2 through the peer hole 7.

After printing a solder paste on the thus formed thick film multilayer board and mounting the chip component 6 thereon, the chip component 6 is connected to the second conductor 4 and the first conductor 2 by the solder 5 by heating and reflowing it. Ru. The connection surface of the second conductor 4 to be soldered, that is, the lower surface of the terminal electrodes 6a, 5b, protrudes from the surface of the insulator 3'', so that the bottom 6c of the chip component 6 and the insulating portion 3° are in contact with each other. Contact with the top surface is avoided, and the level of the chip component 6 can be maintained. Therefore, the bottom part 6c of the chip component 6 comes into contact with the insulating part 3° existing between the electrodes of the chip component 6, and the chip component 6 This has the effect of avoiding the phenomenon of rising.

Next, another embodiment of the present invention will be described with reference to FIG. The reference numerals in the figures indicate the same or equivalent parts as in FIG. 1 above.

The difference between this embodiment and the first embodiment is that in the first embodiment, a pier hole 7 is used to connect the first conductor 2 and the second conductor 4, but in this embodiment, a pier hole 7 is used to connect the first conductor 2 and the second conductor 4. This is a point where the connection is made without using the peer hole.

It is clear that the same effects as in the first embodiment can be obtained in the second embodiment as well.

(Effects of the Invention) According to the present invention, since the connection surface of the chip component with the conductor can be made higher than the multilayer circuit or insulator in the area sandwiched between the connection terminals of the chip component, the bottom of the chip component This has the effect of avoiding the rising phenomenon of parts caused by contact with insulators.

Moreover, this has the effect of improving reliability when mounting and connecting chip components on a thick film multilayer circuit board, and reducing the number of steps required to correct defects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of one embodiment of the present invention, FIG. 2 is a sectional view of a main part of another embodiment of the invention, and FIG. 3 is a sectional view of a conventional device.

Claims (2)

[Claims] (1) In a thick film multilayer circuit board formed by laminating one or more electrode layers and insulating layers alternately printed on a ceramic substrate, the multilayer is located below each terminal electrode of a component to be connected by soldering. 1. A thick film multilayer circuit board characterized in that the circuit structure is greater than the number of layers of the multilayer circuit in the region sandwiched between the respective terminal electrodes. (2) The thick film multilayer circuit board according to claim 1, wherein the region sandwiched between the respective terminal electrodes is an insulating portion.