JPH0249651Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a jumper chip used for electrical connection between conductive wires on a wiring board.

Prior Art A conventional jumper chip has the configuration shown in FIG.

A first conductor layer 2 and a second conductor layer 3 made of silver-palladium are printed on the front and back edges of the substrate 1. Further, a third conductor layer 4 of silver palladium is printed on the side surface of the substrate. These conductor layers are covered with a solder layer 7 via a metal plating layer 5, except for the portion covered with a protective film 6 such as glass.

Problems to be Solved by the Invention However, the jumper chip with the above structure has a complex multilayer structure consisting of a first conductor layer 2, a second conductor layer 3, a third conductor layer 4, a metal plating layer 5, a protective film 6, and a solder layer 7. Because of the structure, many processes are required for thick film printing and firing, which does not improve yield, and also increases costs due to the use of expensive silver-palladium and high utility costs for firing. It was causing problems.

In view of these problems, the object of this invention is to provide a jumper chip that can improve yield and reduce cost by simplifying the structure.

Means for Solving the Problems In order to achieve the above object, this invention forms a base metal layer from the front surface to both ends of the back surface of an insulating substrate, and coats the surface of the base metal layer with tin or solder. It is characterized by the fact that it has been plated.

Function The jumper chip according to the present invention has a two-layer structure consisting of a base metal layer and a plating layer of tin or solder, and the former layer contributes to improving the adhesiveness of the plating layer.

Embodiment FIG. 1 is a sectional view of a jumper chip which is an embodiment of the present invention.

In the figure, reference numeral 10 is a rectangular substrate made of an insulating material such as alumina. Reference numeral 20 denotes a base metal layer formed by electroless plating from the front surface to both ends of the back surface of the substrate. Base metal layer 20
The surface is a plating layer 3 made of tin or solder plating.
Covered with 0. The base metal layer 20 is intended to have good adhesion to tin or solder plating, and is made of nickel or the like which has excellent adhesive strength to the plating. Nickel also has excellent adhesion to the substrate 10 and is preferable as the base metal. The thickness of the base metal layer 20 and the plating layer 30 is 5 to 10 μm. As described above, it is composed of a plating layer of nickel, tin, or solder, and the material cost is lower than that of forming a thick film of silver-palladium.

FIG. 3 shows the mounting state of this jumper chip. 51 to 53 are conducting wires that intersect on the circuit board 50. A jumper chip is placed on the opposing conductors 52 and 53 so as to straddle the middle conductor 51, and when heated solder 60 is placed on the side of the chip, it melts with the tin or solder of the plating layer 30, and the conductors 52 and 53 51, conduction is established through the base metal layer 20 and the plating layer 30.

The manufacturing process of the jumper chip with the above configuration is carried out in the second step.
This will be explained using figures.

Reference numeral 70 is a sheet-like alumina substrate.
First, a plurality of epoxy resin resists 40 are formed in parallel strips at regular intervals on the back surface of the substrate 70 (see FIG. 2a). Subsequently, each resist band is divided along the breaking line M. This division is performed by cutting from slits previously formed in the substrate by braking or disk scribing (see FIG. 2b).

After the strip obtained by the above division is subjected to surface treatment with hydrofluoric acid, electroless plating is performed to form a base metal layer 20 of nickel or the like (see FIG. 2c). Similarly, the strip is plated with tin or solder by electrolytic plating (barrel plating) (see FIG. 2d). Since plating is also applied to the end surfaces of the strip in these steps, both end portions are removed by end treatment.

Next, after performing a peeling process on the resist 40,
Divide the chips into individual chips along the breaking line N of the chip width (see Figure 2d). Note that the division at this time is also performed in the same way as the braking performed in .

As described above, since it can be manufactured using only the resist 40 coating process and the electroless plating and electrolytic plating processes, the printing and baking processes can be reduced and the manufacturing cost can be reduced compared to the case where only thick film formation is used.

Effects of the invention According to the invention, the two-layer structure of the base metal layer and the plating layer reduces material costs, and
The number of manufacturing steps can be reduced and the product can be manufactured at low cost.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a jumper chip that is an embodiment of the present invention, Figures 2 a to e are diagrams for explaining the manufacturing process of the jumper chip, and Figure 3 shows how the jumper chip of the embodiment is used. 4 is a cross-sectional view of a conventional jumper chip. 10... Insulating substrate, 20... Base metal layer, 3
0...Plated layer (of tin or solder).

Claims (1)

[Scope of utility model registration request] A jumper chip in which a base metal layer is formed from the front surface to both ends of the back surface of an insulating substrate, and the surface of the substrate metal layer is plated with tin or solder.