JPS6126171B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a chip-shaped conductive element, in which the front and back surfaces of an insulating substrate, at least a pair of opposing side surfaces, and one of the front and back surfaces of the insulating substrate, and To easily and inexpensively manufacture a chip-shaped conductor element having a substantially rectangular parallelepiped shape, having a continuous conductor layer on at least one pair of side surfaces and an insulator on the other surface. The aim is to provide a method that allows for

In recent years, small leadless chip-shaped parts have been developed for electrical circuit elements such as capacitors, resistors, and semiconductors, and these chip parts are attached to the wiring circuit side (copper surface) of a printed circuit board and soldered. Electronic circuit assembly technology is becoming widespread.

However, in the method of mounting and soldering these chip components on a printed circuit board,
Since the area occupied by chip components is small, the more chip components are mounted on a printed circuit board, the more compact the printed circuit board that makes up the necessary wiring circuits becomes. Because it is difficult to connect many wiring circuits, chip parts are mounted on a printed circuit board, soldered, and then jumper wires made of vinyl-coated copper wire are used to connect wiring circuits that require connection. solder or
A double-sided wiring board with through-hole plating had to be used.

However, the former method not only requires a lot of time and effort for soldering but also has the drawback of being prone to wiring errors, and the latter method has the drawback of increasing the cost of the printed circuit board.

The present invention completely eliminates the above-mentioned drawbacks of the conventional example and efficiently connects wiring circuits that occur when a large number of chip components such as capacitors and resistors are mounted on a printed circuit board and soldered. The present invention provides a method for manufacturing a chip-shaped conductor element.

A feature of the present invention is that an active material for electroless plating is applied to the surface and opposing side surfaces of an insulating substrate processed into a strip shape, and then the strip-shaped insulating substrate is coated with an electroless plating solution. A conductive metal layer is formed on the surface and opposing sides of the insulating substrate on which the active material is formed, and then the strip-shaped substrate is cut into small pieces to produce chip parts having a rectangular parallelepiped shape. It is to do so.

According to this method, it is possible to easily and inexpensively manufacture chip-shaped conductive elements that can extremely easily and reliably establish electrical connections between wiring circuits on a printed circuit board.

Hereinafter, the method for manufacturing a chip-shaped conductor element according to the present invention will be described in detail based on examples.

First, as shown in FIGS. 1A and 1B, an insulating substrate 1 made of a synthetic resin board such as a paper-based phenol laminate, a paper-based epoxy laminate, a glass-based epoxy laminate, or a ceramic is placed on a second insulating substrate 1. As shown in Figures A and B, the chip-shaped conductive elements are cut into strips having the desired width in the longitudinal direction.

Then, activation treatment is performed by immersing this strip-shaped insulating substrate 1' in an activation treatment solution consisting of, for example, an acidic solution of stannous chloride in hydrochloric acid and an acidic solution of palladium chloride in hydrochloric acid, as shown in FIG. Palladium fine particle nuclei, which serve as catalyst nuclei for electroless plating, are attached to the front and back surfaces and opposing side surfaces of the strip-shaped insulating substrate 1' to form an active matrix 2.

Next, as shown in FIGS. 4A and 4B, this strip-shaped insulating substrate 1' is immersed in a known electroless nickel plating solution or electroless copper plating solution to remove the insulating substrate on which the active substrate 2 has been formed. A conductive metal 3 made of nickel or copper is deposited on the front and back surfaces and opposing side surfaces. Then, if necessary, electroplating is performed to strengthen the thickness of the metal layer such as nickel or copper, and then metal such as tin or solder is plated on top of the layer of copper or copper.
Prevents corrosion of the nickel metal layer and improves solderability. Next, as shown in FIG. 5, this strip-shaped insulating substrate 1' is cut into small pieces according to the dimensions of a desired chip-shaped conductor element, thereby forming a chip-shaped component 4 having a rectangular parallelepiped shape.

Note that in this method, instead of cutting the insulating substrate 1 into strips, as shown in FIG. ,5c,
5d, a conductive metal layer 3 is formed on the front and back surfaces of this insulating substrate 1 and the wall surface of the through groove by the method described above as shown in FIG. 7, and then this substrate is cut into strips. By cutting the substrate into small pieces, a chip-shaped component as shown in FIG. 5 may be obtained.

In addition, in this method, an adhesive is applied to the front and back surfaces of the insulating substrate 1, the surface of the adhesive layer is roughened, and then a conductive metal layer is formed by the above-mentioned method. Chip-shaped conductive elements with excellent adhesion can be made.

A suitable adhesive for this purpose is, for example, nitrile rubber crosslinked with phenolic resin or epoxy resin, and this adhesive layer is
Etch with a sulfuric acid solution or potassium permanganate solution to form a phase.

The chip-shaped conductor obtained in the above embodiments has a structure having a continuous conductive metal layer on the front and back surfaces of an insulating substrate and a pair of opposing side surfaces; When chip-shaped conductive elements are soldered between wiring insulation using printed circuit board connections, they are used only when no other independent wiring circuit is configured between the wiring circuits that require connection. .

On the other hand, if another independent wiring circuit is configured between the wiring circuits that require connection of the printed circuit board, one of the front and back surfaces of the insulating board is made of an insulator, and the other side , a chip-shaped conductor element must be used in which a continuous conductive metal layer is formed on a pair of opposing side surfaces.

As shown in FIG. 8, a chip-shaped conductor element having such a structure has acid resistance on one of the front and back surfaces of the insulating substrate 1 made of the above-mentioned synthetic resin or ceramic, and is resistant to dilute alkaline solutions or A resist 6 that can be easily removed with a solvent is applied, and after drying the resist 6, the insulating substrate 1 is cut into strips as shown in FIG. In this case, it goes without saying that the insulating substrate 1 may be processed into the shape shown in FIG. 6 mentioned above.

Next, the strip-shaped insulating substrate 1' is activated by being sequentially immersed in the above-mentioned activation treatment solution consisting of an acidic solution of stannous chloride in hydrochloric acid and an acidic solution of palladium chloride in hydrochloric acid. As shown in FIG. 10, the active material 2 for electroless plating remains only on one surface of the insulating substrate and the opposing side surface.

The strip-shaped substrate 1' is then immersed in an electroless plating solution to form a conductive metal layer 3 on the active substrate 2, as shown in FIG. In this case, one surface of the strip-shaped substrate 1' on which the resist 6 was applied has not been subjected to activation treatment, so that no conductive metal layer is formed. After that, this strip-shaped insulating substrate 1'
is cut into small pieces as shown in FIG. 12 to form chip parts 4'.

In this method, an adhesive is applied to the surface of an insulating substrate as described above, the adhesive layer is etched to roughen the surface, and a conductive metal layer is then formed to form a chip-shaped conductive element with excellent adhesion. Needless to say, you can obtain

The chip-shaped conductor elements obtained in the above embodiments can be mounted and soldered with the conductor side facing upward, regardless of the presence or absence of other independent wiring circuits between the wiring circuits that require connection to the printed circuit board. This makes it possible to easily and reliably connect wiring circuits.

As explained above, the chip-shaped conductor element obtained by the present invention can be mounted and soldered to a printed circuit board together with other chip parts such as capacitors and resistors, so that it can be mounted and soldered on a printed circuit board after the chip parts have been attached as in the conventional method. Compared to the method of soldering with jumper wire, assembly efficiency is significantly improved. Furthermore, the chip-shaped conductor elements obtained by this method have the advantage of being highly mass-producible and can be manufactured at low cost.In addition, by using this chip-shaped conductor element, chip-shaped circuit elements such as capacitors, resistors, and semiconductors can be manufactured. It has great effects, such as being able to use it effectively and rationally.

[Brief explanation of the drawing]

Figure 1A, Figure 2A, Figure 3, Figure 4A, Figure 5
6 and 7 are perspective views showing the method of the present invention, FIGS. 1B, 2B, and 4B are side views, and FIGS. 8 to 11 are side views, and FIGS. FIG. 12 is a perspective view of the same. DESCRIPTION OF SYMBOLS 1... Insulating substrate, 1'... Strip-shaped insulating substrate, 2... Active base material, 3... Conductive metal layer, 4, 4'... Chip parts, 5a, 5b, 5c, 5d... Penetration groove, 6... Acid-resistant resist.

Claims (1)

[Claims] 1. A step of imparting activity for electroless plating to the front and back surfaces and both side surfaces of a strip-shaped insulating substrate, a step of forming a conductive metal layer on the strip-shaped insulating substrate by an electroless plating method, A method for manufacturing a chip-shaped conductive element, comprising the step of cutting the strip-shaped insulating substrate into small pieces, and forming continuous conductive metal layers on the front and back surfaces and both side surfaces of the strip-shaped insulating substrate. 2 Apply adhesive to the front and back sides of the strip-shaped insulating board,
2. The method of manufacturing a chip-shaped conductive element according to claim 1, wherein the surface of the adhesive is roughened in advance. 3. A step of applying a resist to one of the front and back surfaces of the strip-shaped insulating substrate, a step of activating the entire surface of the strip-shaped insulating substrate for electroless plating,
a step of removing the resist from the strip-shaped insulating substrate; a step of forming a continuous conductive metal layer on a surface opposite to the resist-coated surface of the strip-shaped insulating substrate and both side surfaces by electroless plating; A method for manufacturing a chip-shaped conductive element, comprising the step of cutting the strip-shaped insulating substrate into small pieces. 4. The method for manufacturing a chip-shaped conductive element according to claim 3, characterized in that an adhesive is applied to the surface of the strip-shaped insulating substrate, and the surface of the adhesive layer is roughened in advance.