JPS641077B2 - - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method of forming a thick film pattern for an external lead or contact formed on a final constituent layer on a base substrate such as ceramic.

Prior Art and Problems A conventional thick film pattern 1 of this type is shown in FIG. The thick film pattern 1 is formed on the final constituent layer of the base substrate 2 by screen printing.

However, this thick film pattern 1 is likely to peel off due to thermal stress or external stress during soldering of members connected to the thick film pattern 1, and countermeasures are desired.

Purpose of the Invention The present invention is intended to realize the above-mentioned desire.
It is an object of the present invention to provide a method for forming a thick film pattern that can prevent the thick film pattern formed on the final constituent layer of a base substrate from peeling off due to thermal stress, external stress, etc.

Structure of the Invention In order to achieve the above-mentioned object, in the present invention, a protruding pattern is formed at a thick film pattern forming position on the final constituent layer of a base substrate, and then a protruding pattern is formed on the protruding pattern, and then a protruding pattern is formed on the protruding pattern in the vicinity of the protruding pattern. After forming a conductor pattern (thick film pattern) spanning the final constituent layer in a frame shape by screen printing, an overcoat of an insulator is formed on the final constituent layer to reach the frame-shaped periphery of the conductor pattern. The frame-shaped peripheral portion of the conductor pattern is pressed down by the overcoat.

Embodiments of the Invention Hereinafter, embodiments of the invention will be described with reference to FIGS. 2 and 3.

FIG. 2 is a cross-sectional view showing a thick film pattern formed by the method of the present invention. In the figure, 11 is a base substrate made of ceramic or the like, and 12 and 13 are a lower conductor pattern and an insulating layer formed on the base substrate 1. , 14
is the insulating layer formed on these (final constituent layer),
15 is a protruding pattern, 16 is a conductor pattern (thick film pattern), and 17 is an overcoat.

Next, the procedure for forming a thick film pattern will be explained with reference to FIG.

Figure 3a shows the state before thick film pattern formation;
The insulating layer 14 corresponds to the final constituent layer on the base substrate 11.

When forming a thick film pattern, first the insulating layer 1 is
A protruding pattern 15 is formed at a predetermined position on 4 by printing as shown in FIG. 3b. This protruding pattern may be an insulator or a conductor, and its selection is made as appropriate depending on the application. Next, as shown in FIG. 3c, a conductive pattern 16 is formed on the protruding pattern 15 by printing so as to span the insulating layer 14 around the protruding pattern 15 in a frame shape. This conductor pattern 16 corresponds to a thick film pattern to be formed. Finally, as shown in FIG. 3d, the insulating layer 14
An insulating overcoat 17 is formed thereon to reach the frame-shaped peripheral portion 18 of the conductor pattern 16, thereby completing the formation of the thick film pattern.

Note that the connecting member is the exposed portion (portion not covered by the overcoat 17) 1 of the conductor pattern 16.
Connected to 9.

Effects of the Invention As described above, according to the present invention, the frame-shaped peripheral portion of the conductive pattern (thick film pattern) formed by printing on the final constituent layer is pressed and reinforced by the insulating overcoat. By increasing the adhesion area of the thick film pattern, it is possible to solve the conventional problem of peeling due to thermal stress and external stress.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional thick film pattern formed on the final constituent layer of a base substrate, FIG. 2 is a sectional view showing a thick film pattern formed by the method of the present invention, and FIGS. 3 a to d is a process diagram for forming the thick film pattern in FIG. 2, in which 11 is a base substrate, 14 is an insulating layer (final constituent layer), 15 is a protruding pattern, 16 is a conductor pattern (thick film pattern), and 17 is a An insulator overcoat 18 is a frame-shaped peripheral portion of the conductor pattern.

Claims (1)

[Claims] 1. In a method of forming a thick film pattern on a substrate, a protruding pattern is formed at a thick film pattern forming position on the substrate, and then a picture frame is formed on the protruding pattern and around the protruding pattern on the substrate. 1. A method for forming a thick film pattern, comprising: forming a thick film conductor pattern that spans a shape, and then forming an insulating overcoat on the substrate that reaches a frame-like peripheral portion of the conductor pattern.