JPS6034096A - Thick film circuit and method of producing same - 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 (a) Technical field to which the invention pertains The present invention relates to a thick film circuit and a method for manufacturing the same.1 In particular, the present invention relates to a thick film circuit and a method for manufacturing the same. The present invention relates to a method for manufacturing a thick film circuit having a cross-over structure and a cross-over structure thereof.

(b) Description of the prior art When performing multilayer wiring in a thick film circuit, there are no pinholes between the lower conductors, an insulator with high withstand voltage is used, and the printability of the upper conductor is good (i = good). 9. A thick film circuit is required in which the upper conductor does not break at the edge of the insulator.

A conventional thick film circuit of this type and its manufacturing method will be explained with reference to FIGS. 1 to 3.

As shown in FIGS. 1 and 2, the thick film circuit is manufactured by the following steps. That is, first, the lower conductor 3 is printed on the insulating substrate 1 by sandwiching the lower conductor 2 and the lower conductor 2, and then dried and fired. Next, the insulator 4 is printed and dried on the lower conductor 2. The dry thickness of the insulator layer is approximately 50-60 pm
It is. Subsequently, the upper conductor 5 is printed on the insulator 4, dried, and fired together with the insulator 4.

Or as another method, as shown in FIG.
Then, an insulator 4a is printed on the lower conductor 2 and dried.

The insulator 4b is printed again using the same pattern mask and dried to form a two-layer structure. The total dry thickness of the insulator layer is approximately 50-60
It is μm. Subsequently, the upper conductor 5 is printed 1 on the insulator 4b, dried, and fired together with the insulator.

In the two-force method, the insulator 4 or 4d%4b is printed and dried, and the upper conductor 5 is printed, dried, and fired at the same time, but the printing, drying, and firing are repeated to form multilayer wiring. It has also been done.

However, in the above conventional method, the thickness of the insulator layer is quite large, and the printability of the upper conductor 5 is poor due to the step E of the insulator, and the upper conductor 5 becomes thinner and blurred. had the disadvantage of causing wire breakage.

In order to eliminate the above-mentioned drawbacks, conventional methods include printing the upper conductor 5 twice in succession to increase the amount of conductor paste in the E section, or designing the upper conductor 5 to be wider than the lower conductor 2.3. Some methods were being tried. Also, a method has been adopted in which the upper conductor is designed to be wide only at the step E portion.

However, none of the above methods provided an effective solution, and either the original drawbacks described above still remained or other new drawbacks caused by these methods were derived.

(C), Purpose of the Invention The present invention has been made to eliminate the above-mentioned drawbacks inherent in the conventional technology.1 Therefore, the purpose of the invention is to improve the shape and area of insulators when performing multilayer wiring. Printing is performed two or more times with two or more pattern masks, thereby forming an insulator with stepped steps, and having a thickness sufficient for insulation, causing disconnection of the upper conductor at the edge of the insulator. An object of the present invention is to provide a novel thick film circuit and a method for manufacturing the same.

(d) Structure of the Invention In order to achieve the above object, the thick film circuit according to the present invention includes a lower conductor formed on an insulating substrate, and at least two conductors formed on the lower conductor. The method for manufacturing a thick film circuit according to the present invention includes a stepped insulator having steps and an upper conductor formed on the insulator, and a method for manufacturing a thick film circuit according to the present invention includes forming a lower conductor on an insulating substrate. , at least two
The present invention is characterized in that a step-like insulator having steps is formed by screen printing using at least two types of pattern masks, and a conductor is formed on the insulator to perform multilayer wiring.

(e) Detailed Description of the Invention Hereinafter, a preferred embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 4 shows the main part (
Crossover structure) Plan view, Figure 5 shows b-b in Figure 4.
It is a sectional view taken along the line ' and viewed in the direction of the arrow.

4 and 5, reference number l indicates an insulating substrate, on which a lower conductor 2 is disposed in the y-axis direction, and a lower conductor 3 is disposed in the x-axis direction except for the middle portion including the origin. each formed. Insulators 4c and 4d are formed on the lower conductor 2 with the origin as the center, and the insulator 4c and the insulator 4d
A step-like step F is provided between the two. Insulator 4
An upper conductor 5 is formed on the cs4d, and both ends thereof are connected to the lower conductor 3, respectively.

Next, to explain the method for manufacturing a thick film circuit according to the present invention, first, the lower conductor 2 is placed on the insulating substrate 1 in the X-axis direction.
The lower conductor 3 is printed, except for the middle portion including the origin in the X-axis direction, and then dried and fired. Next, an insulator 4C is printed on the lower conductor 2 using a first pattern mask,
dry. Next, the insulator 4d is patterned using a second pattern mask whose area is slightly smaller than the first pattern mask, that is, the insulator 4C%, so that a step is formed in the direction in which the upper conductor is wired. Print on the insulator 4c and dry. Next, an upper conductor 5 is printed on the overprinted insulator 4C14d, crossing the lower conductor 2, and both ends of the upper conductor 5 are connected to the corresponding lower conductor 2, dried, and fired at the same time.

In the above example, in order to reduce the number of steps, after printing and drying the upper conductor 5, the insulator 4c and subsequent parts are fired at the same time, but the insulator 4ON4d% upper conductor 5 is fired individually. Also good. In this case, the total number of firing times is four. Further, the number of firings may be three times.

Furthermore, in the above embodiment, an insulator having two steps using two types of pattern masks was explained.
It is also possible to provide three or more steps using three or more types of pattern masks.

In this case, the effect is that the occurrence of pinholes is exponentially reduced.

Furthermore, in this example, a step is provided only in the X-axis direction of the insulator using pattern masks that differ only in length in the X-axis direction and have the same length in the y-axis direction. It is also possible to eliminate directivity when forming the upper conductor by forming steps not only in the X-axis direction of the insulator but also in the y-axis direction using similar pattern masks with different lengths in the directions.

(f) Detailed Description of the Invention The present invention is constructed and operates as described above, and the present invention provides the following effects.

That is, by performing multilayer wiring according to the above method according to the present invention, there is no generation of pinholes between the lower conductor and the upper conductor, sufficient insulation is obtained, and the total thickness of the insulation layer is No, the height difference of the insulator is 25~307cm after drying.
7 m, but by firing it can be reduced to 20 to 25 μm, less than half that of conventional methods.

An even greater effect is that since a step-like step is formed around the insulating layer, the printability of the upper conductor formed thereon is good, and the occurrence of troubles such as disconnections as in the past is eliminated. The defective rate is significantly reduced. Further, there is an advantage that inspections for withstand voltage, disconnection, etc. are not required.

Still, according to the present invention, since the bleeding that occurs at the step F when printing the upper conductor is suppressed, the interval between the upper conductors can be narrowed, and as a result, the wiring density can be increased.

[Brief explanation of the drawing]

Figure 1 is a schematic plan view of a conventional multilayer wiring thick film circuit.
Fig. 2 is a sectional view taken along line a-a' in Fig. 1 and seen in the direction of the arrow, Fig. 3 is a sectional view similar to Fig. 2 of another conventional example, and Fig. 4 is a sectional view of Fig. 1. A schematic plan view showing an embodiment of the multilayer wiring thick film circuit according to the present invention, FIG.
FIG. 3 is a sectional view taken along line -b' and viewed in the direction of the arrow. 1.Insulating board, 2.3Φ...lower conductor, 4.4a,
4b, 4c, 4ds*e insulator, 56. . Upper conductor, E, F...middle level difference Patent applicant Okura Electric Co., Ltd. Representative Patent attorney Yuta Kumagai 1 Figure N2 Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) A lower conductor formed on an insulating substrate, a stepped insulator having at least two steps formed on the lower conductor, and an upper conductor formed on the insulator. A thick film circuit that is characterized by: (2) forming a lower conductor on an insulating substrate, forming a stepped insulator having at least two steps on the lower conductor by screen printing technology using at least two types of masks; A method for manufacturing a thick film circuit, comprising forming an upper conductor on the insulator to perform multilayer wiring.