JPS6262501A - Thick film substrate unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a thick film substrate device, and particularly to one in which resistor layers having different resistance values can be easily formed.

[Technical Background of the Invention] As is well known, in recent years, hybrid integrated circuits have come into widespread use in order to reduce the size and weight of electronic devices and the like. This hybrid integrated circuit is generally constructed by soldering chip-type passive elements and active elements without lead wires to a thick film substrate formed by printing a conductive material and a resistive material on an insulating substrate.

FIG. 13 shows such a conventional thick film substrate. That is, for example, a silver-palladium based conductive paste is printed on an insulating substrate 11 made of a ceramic material such as alumina using a screen printing method, and then baked at a high temperature of about 800 to 900° C. in an oxidizing atmosphere. Then, the lower conductor layer 12 is formed.

Next, an insulating layer 13 is formed by printing and baking, for example, a glass-based insulating paste so as to cover a predetermined portion of the lower conductor layer 12 . Thereafter, a ruthenium oxide-based resistance paste, for example, is printed on the insulating substrate 11 so as to overlap the lower conductor layer 12, and a conductor paste is printed on the insulating layer 13 and fired at the same time, thereby forming a resistor. Layers 14, 15 and upper conductor layer 16 are formed.

Here, the resistor layer 14 formed in a film shape as described above.
As shown in FIG.
．． If the membrane resistance value per unit area of 15 is Rs, it is expressed as R-Rs L/W-(1). For this reason, for example, the resistance value of the resistor layer 14 is set to 100Ω after firing, and the resistance value of the resistor layer 15 is set to 50Ω after firing.
In such a case, the resistor layer 14 is made of Rs −
100Ω resistive paste at L −1av.

Print in the shape of W=1a+a, and use R5 as the resistor layer 15.
-50 Ω resistance paste L -0, Ba+m, W
It is sufficient to print in the shape of -1,2IIal.

By the way, in general, the resistance paste has a film resistance Rs of, for example, 10Ω, 100Ω, lkΩ, [OkΩ.

1. They are often classified into resistance values of 1 digit, such as OOkΩ, etc., and when designing the printed shape of resistor paste, consider, for example, the influence of noise, ease of trimming, and resistance value. In consideration of fluctuations in heat generation, etc., a resistor paste is selected and used so that the area occupied by the resistor layer is minimized as far as performance allows.

[Problems in the Background Art] However, in the conventional thick film substrate as described above, multiple resistor layers having different resistance values are formed in a manner that reduces the area occupied and promotes high-density packaging. In this case, it is necessary to select and use a plurality of resistor pastes with different film resistance values Rs, so screens must be prepared for each type of resistor paste to be used, and printing must be repeated for each type. First, there is a problem in that the manufacturing work tends to be complicated.

[Object of the Invention] This invention has been made in consideration of the above circumstances, and it is possible to achieve a
It is an object of the present invention to provide an extremely good thick film substrate device that can easily form a plurality of resistor layers having different resistance values and can effectively promote high-density packaging.

[Summary of the Invention] That is, in the thick film substrate device according to the present invention, a resistor layer is formed so as to partially overlap a first conductor layer formed on an insulating substrate, and a resistor layer is formed on the resistor layer. By forming the second conductor layer so as to partially overlap and changing the shape and thickness of the resistor layer to soften its resistance value,
A plurality of resistor layers having different resistance values can be easily formed without using many types of resistor pastes having different film resistance values, and high-density packaging can be effectively promoted. It is something.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In FIG. 1, 17 is an insulating substrate made of a ceramic material such as alumina. On this insulating substrate 17, a lower conductor layer 1B is formed by printing, for example, a silver-palladium conductor paste using a screen printing method and firing it at a high temperature of about 800 to 900°C in an oxidizing atmosphere. There is. An insulating layer 19 is formed on the lower conductor layer 18 to cover a predetermined portion of the lower conductor layer 18, for example, by printing and baking a glass paste.

Further, a ruthenium oxide-based resistance paste is printed on the lower conductor layer 18 so as to partially overlap with it, and a conductor paste is printed on the insulating layer 19 and fired at the same time, thereby forming a resistor. A body layer 20, 21 and an upper conductor layer 22 are formed.

Here, for example, if you want to set the resistance value of the resistor layer 21 to 50Ω, apply a resistive paste with a film resistance Rs of 100Ω to L −0,6tm, W−1,2r in the same manner as described above.
It is sufficient to print it in the shape of Aal. Further, the resistor layer 20 can be made to have a different resistance value from the resistor layer 21 by using a resistor paste having a film resistance value of 100 to Ω, which is the same as the resistor layer 21.

That is, as shown in FIGS. 2(a) and 2(b), if the end of the lower conductor layer 18 is formed in a shape of 0.8+nm in length and 0.5+++n+ in width, The resistor paste was printed in the shape of 1 mrfI of 0.7 mm horizontally, and the conductor paste for forming the upper conductor layer 22 was printed on top of it in the shape of 0.8 mm vertically and 0.5 a+a+ horizontally. It's a good thing.

The reason for this can be explained as follows.

Generally, the resistance value R of a resistor is determined by the area of the electrode surface 23a of the resistor 23 being S, and the distance between the electrodes being d, as shown in FIG.
, when the specific resistance value of the resistor 23 is ρ, R−ρd/S
...(2) can be expressed.

In addition, in FIG. 3, 24 indicates both electrode surfaces 2 of the resistor 23.
3a, respectively.

Here, especially if the electrode surface 23a has a rectangular shape with a vertical length a and a horizontal length b, the resistance value R is R-ρd/
ab...(3).

Then, from the above equations (1) and (3), the relationship between the membrane resistance value Rs of the resistor 23 and the specific resistance value ρ of the resistor 23 is found, L corresponds to d, and W corresponds to b. Since it corresponds to Rs-
ρ/a...(4). Here, a
corresponds to the thickness of the resistor layer 20. and,
For example, if the thickness a is 20 μm, it can be seen from equation (4) above that the specific resistance p of a resistive paste with a membrane resistance value Rs of 100Ω is 200Ωcm. For this reason, this resistance paste with a membrane resistance value of 2 (10ΩcII) was used with a distance between electrodes of 20 μm and a length of 0.8 mm.

If a rectangular electrode shape with a width of 0.5 mm is formed by printing, the resistance value after firing will be 100Ω from the above equation (3).

Therefore, according to the configuration of the above embodiment, the same 1
Using a resistor paste having a film resistance value Rs of 0.00 to .OMEGA., it is possible to form a resistor layer 20 having a resistance value of 100 .OMEGA. and a resistor layer 21 having a resistance value of 50.OMEGA. Therefore, it is not necessary to select resistor pastes having a wide variety of film resistance values Rs as in the conventional case, and the number of printing steps for resistor pastes is reduced, making it possible to simplify the manufacturing work.

Further, the lower conductor layer 18. Since the resistor layer 20 and the upper conductor layer 22 are configured to be stacked, they are suitable for high-density packaging.

FIGS. 4 and 5 each show a modification of the above embodiment. First, Fig. 4(a).

In the structure shown in FIG. 2B, the lower conductor layer 18 and the upper conductor layer 22 are arranged so that they do not overlap in a plane with the resistor layer 20 in between. In addition, in the case shown in FIGS. 5(a) and 5(b), the lower conductor layer 18 and the upper conductor layer 22 are arranged so that they do not overlap in a plane with the resistor layer 20 in between. The lower conductor layer 18 and the two-layer conductor layer 22 are formed so as to have a distance Ll greater than the thickness of the resistor layer 20.

Here, the distance L1 between the lower conductor layer 18 and the upper conductor layer 22 is
The relationship between the resistance value of the resistor layer 20 and the resistance value of the resistor layer 20 is such that as the distance 4L1 increases, the resistance value increases as shown in FIG. Incidentally, FIG. 6 shows the results of an experiment in which all the resistance pastes were determined using a resistance paste whose film resistance value Rs was 100Ω.

Next, FIGS. 7 to 9 each show the state in which the trimming process has been applied to the embodiment described above as the second factor. First, in the case shown in FIGS. 7(a) and 7(b), only the upper conductor layer 22 is trimmed and the upper conductor layer 22 is trimmed.
A cutting portion 25 is formed in the second portion. Also, FIG. 8(a).

What is shown in (b) is a double-layer conductor layer 22 and a resistor layer 2.
0 is subjected to trimming processing.

Furthermore, what is shown in FIGS. 9(a) and 9(b) is an upper conductor layer 22. The resistor layer 20 and the lower conductor layer 18 are trimmed.

Further, FIGS. 10 to 12 each show a state in which the embodiment shown in FIG. 5 has been subjected to trimming processing. First, what is shown in FIGS. 10(a) and (b) is
A trimming process is performed only on the resistor layer 20 to form a cut portion 26 in the resistor layer 20. What is shown in FIGS. 11(a) and 11(b) is a portion where the lower conductor layer 18 and the resistor layer 2o overlap.
The trimming process is applied only to 0.

Further, in the case shown in FIGS. 12(a) and 12(b), the resistor layer 2o and the lower conductor layer 18 are trimmed.

Here, the trimming process is performed for the purpose of increasing the resistance value by reducing the path through which current flows, and in practice, a laser trimming method, a sandblasting method, or the like is used.

It should be noted that the present invention is not limited to the above-described embodiments, and can be implemented with various modifications without departing from the gist thereof.

[Effects of the Invention] Therefore, as detailed above, according to the present invention, a plurality of resistor layers having different resistance values can be easily formed without using many types of resistor pastes having different film resistance values. In addition, it is possible to provide an extremely good thick S substrate device that can effectively promote high-density packaging.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of a thick film substrate device according to the present invention, FIG. 2 is a configuration diagram showing the shape of the main part of the embodiment, and FIG. 3 is a diagram illustrating the operating principle of the embodiment. A perspective view for explanation, FIGS. 4 and 5 are configuration diagrams showing the trimming process of the same example, and FIG. 6 shows the distance between the upper conductor layer and the lower conductor layer and the resistance of the resistor layer. Characteristic diagrams showing the relationship with values, Figures 7 to 9 are configuration diagrams showing the state in which the substrate shown in Figure 2 has been trimmed, and Figures 10 to 12 are shown in Figure 5, respectively. A configuration diagram showing a state where the substrate has been subjected to trimming processing, and FIGS. 13 and 14 are a side sectional view and a plan view, respectively, showing a conventional thick film substrate. 11... Insulating substrate, 12... Lower conductor layer, 13...
- Insulating layer, 14, 15... Resistor layer, 16... Upper conductor layer, 17... Insulating substrate, 18... Lower conductor layer,
19... Insulating layer, 20.21... Resistor layer, 22...
...Upper conductor layer, 23...Resistor, 24...Connection line, 25, 28...Cutting portion. Applicant's agent Patent attorney Takehiko Suzue (a) Figure 9 (a) Figure 10 (a) Figure 11 (a) Figure 12

Claims (1)

[Claims] a first conductor layer formed on an insulating substrate; a resistor layer formed on the insulating substrate so as to partially overlap with the first conductor layer; and a resistor layer partially overlap with the resistor layer. a second conductor layer formed as described above, and the resistance value of the resistor layer is changed by changing the shape and thickness of the resistor layer.