JPH0691129B2 - Method of interconnecting electrode terminals and method of manufacturing electrical connection structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to interconnection of electrode terminals for electrically interconnecting electrode terminals of a wiring board facing other wiring boards and the like through conductive fine particles. The present invention relates to a method and a method for manufacturing an electrical connection structure.

[Prior Art and Problems to be Solved by the Invention] Conventionally, electrode terminals have been interconnected by the connection method disclosed in Japanese Patent Laid-Open No. 54-152470. However, in this method, the conductive particles and the constituent material of the electrode terminal are limited to the ferromagnetic material, so that the selection range of the material is narrow, and since the particles are connected in a chain in the magnetic force line direction, the other electrode terminal There is a problem that particles are distributed to unnecessary places during the pressure welding connection of.

The object of the present invention is to solve the problems of the conventional art.
In the method of interconnecting electrode terminals and the method of manufacturing an electrical connection structure, it is possible to disperse conductive fine particles only in a necessary portion on a wiring board.

[Means for Solving the Problem] In order to achieve this object, in the method of interconnecting electrode terminals and the method of manufacturing an electrical connection structure of the present invention, an electric field is concentrated on the first electrode terminals provided on the surface of the substrate. In the electrostatic field,
The electrically conductive fine particles are selectively applied onto the first electrode terminals by spraying the electrically conductive fine particles, and then the second electrically conductive fine particles are applied to the first electrode terminals through the second electrically conductive fine particles. It is characterized in that electrode terminals are connected.

Here, in order to concentrate the electric field on the first electrode terminal,
For example, the first electrode terminal may be held at a ground potential or a potential having a polarity opposite to the charge potential of the conductive fine particles. Also,
It is preferable to charge the surface of the substrate other than the first electrode terminal to a potential having the same polarity as the charging potential of the conductive fine particles. For this purpose, for example, the substrate surface may be an insulator made of a dielectric material and corona discharge may be used. There is a method of attaching free ions generated by the above to the surface of the insulator, or a method of providing an electric potential by providing an electrode pattern on the surface of the substrate.

[Operation] According to this, the charged conductive fine particles are dispersed in the electrostatic field in which the electric field is concentrated on the first electrode terminal provided on the surface of the substrate. 1
Is selectively sprayed only on the electrode terminals. Further, at that time, the conductive fine particles do not form a chain. Therefore, when connecting the second electrode terminal through the conductive fine particles, the conductive fine particles are not disposed even in an unnecessary portion, and the highly reliable interconnection of the electrode terminals is performed. A reliable electrical connection structure is manufactured.

In addition, by charging the surface of the substrate other than the first electrode terminal to a potential having the same polarity as the charging potential of the conductive fine particles, electrostatic stress between the substrate surface and the conductive fine particles may cause an unwanted portion to reach an unnecessary portion. Adhesion of the conductive fine particles is more effectively prevented.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 5 shows a method of spraying conductive particles according to a basic embodiment of the present invention.

As shown in the figure, in order to electrically interconnect the electrode terminals 4 of the wiring board facing each other through the conductive fine particles, the conductive fine particles 10a are passed through the corona electric field created by the corona discharge electrode 1. The charged conductive fine particles 10b are dispersed on the electrode terminals 4 of the wiring board in an electrostatic field in which the electric field is concentrated. According to this, by the electric field concentrated on the electrode terminals 4, the conductive fine particles are selectively dispersed almost only on the electrode terminals 4. Further, at that time, the conductive fine particles do not form a chain. Therefore, by connecting the electrode terminals through the conductive fine particles dispersed in this way, the conductive fine particles are not disposed even in an unnecessary portion, and highly reliable interconnection of the electrode terminals can be performed. Therefore, a reliable electrical connection structure is manufactured.

1 (a) and 1 (b) show a method of spraying conductive particles according to an embodiment of the present invention.

In the figure, 1 is a conductive fine particle 10a by corona discharge.
Corona charging pin (corona discharge electrode) for charging
2 is a high voltage power supply for applying a voltage to the corona charging pin 1, 4 is an electrode (terminal) of the wiring board, 6 is a base board of the wiring board, 7 is a flat plate electrode (electrode plate), 13 is the flat plate electrode 7 grounded. Reference numeral 9 is a ground wire for setting the potential, 9 is a spray gun for guiding the conductive fine particles to the corona charging pin, and 8a is a ground wire for setting the electrode terminal of the wiring board to the ground potential.

In order to disperse the conductive particles on the wiring board in this configuration, first, as shown in FIG. 1 (a), an insulating layer made of a dielectric material is applied to the portion 5 where the conductive fine particles are not desired to be attached. Object 5 is provided, the wiring board is positioned between the corona discharge electrode 1 and the electrode plate 7 grounded to the ground potential, and free ions (minus ions) 3a generated from the corona discharge electrode 1 are placed on the insulating film 5. And the insulating film 5 is charged.

Then, as shown in FIG. 1 (b), the conductive fine particles 10a
Are passed through a corona electric field created by the corona discharge electrode 1 to be charged. As a result, charged conductive fine particles
10b is an electrostatic field created between the discharge electrode 1 and the ground electrode or the take-out electrode 4 of the wiring substrate, which has a polarity opposite to the charged potential of the conductive fine particles. It is guided and adheres to the connection portion of the extraction electrode 4. At this time, since the insulating film 5 is charged to the same potential as the charged fine particles 10b, the charged fine particles 10b are repelled by the electrostatic stress to the insulating film 5, and the conductive fine particles on the insulating film 5 are repelled. It can avoid sticking to.

2 (a) and 2 (b) show a method according to another embodiment of the present invention. In this method, first, in order to give a potential on the wiring substrate where the conductive fine particles are not desired to be attached to a potential having the same polarity as the charging potential of the conductive fine particles, an electrode pattern 12 is provided on that region, which is described above. In the same manner as above, the conductive particles are charged to the same polarity as the charging potential.

Then, as shown in FIG. 2 (b), the conductive fine particles 10a are charged in the same manner as described above and sprayed in an electrostatic field.
At this time, since the electrode pattern 12 is charged to the same polarity as the charging potential of the conductive fine particles, the charged conductive fine particles 10b are charged.
Is repelled by electrostatic stress due to the electrode pattern 12,
It is possible to prevent the conductive fine particles from adhering to the electrode pattern.

FIG. 3 shows still another embodiment. In order to have a potential of the same polarity as the charging potential of the conductive fine particles on a portion of the wiring board where the conductive fine particles are not desired to be attached, the point that the electrode pattern 12 is provided is similar to the above, but here A potential is applied to the electrode pattern 12 by a power source 14, and thereafter, the conductive fine particles are charged in the same manner as described above, and are dispersed in an electrostatic field. At this time, the electrode pattern 12 is the conductive fine particles 10b.
Since a potential having the same polarity as the charging potential of is charged, the charged conductive fine particles 10b are repelled by the electrode pattern 12 due to electrostatic stress, and the conductive fine particles 10b become
2 can avoid sticking on.

Furthermore, as shown in FIG. 4, electrode terminals 4 on the wiring board
The power source 8a is applied with a potential having a polarity opposite to the charged potential of the conductive fine particles 10b.
May be given by this, thereby increasing the electrostatic attractive force between the charged conductive fine particles 10b and the electrode terminal 4,
As compared with the case of FIG. 3A, the conductive fine particles can be made to adhere to the electrode terminals more easily.

[Effects of the Invention] As described above, the present invention has the following effects.

That is, the charged conductive particles are dispersed in an electrostatic field in which the electric field is concentrated on the electrode terminals provided on the surface of the substrate, or further, the surface of the substrate other than the electrode terminals is charged to the charged potential of the conductive particles. Since the conductive particles are charged to the same polarity as the conductive particles, it is possible to prevent the conductive particles from adhering to a portion of the wiring board where the conductive particles are not required.

This makes it possible to prevent conductive particles from adhering to areas other than the electrode terminals of the wiring board that are connected to each other, and the insulation resistance between the wirings is high and the electrical conductivity of the wiring board is high. Interoperability.

Also, when conductive particles are used to make a face-down connection of semiconductor elements on the wiring board, the conductive particles should adhere to the portions corresponding to the die edges of the semiconductor elements on the wiring board. It is possible to prevent the occurrence of an edge short circuit between the wiring board and the semiconductor element.

Further, when electrically connecting interconnecting wiring boards using conductive fine particles, it is necessary to avoid adhesion of the conductive fine particles to a portion narrower than the gap between the electrode terminals connected to each other. Therefore, when the wiring boards are connected by pressure bonding, the gap between the electrode terminals facing each other can be narrowed and the conductive fine particles can be sandwiched without any trouble.

Further, by increasing the potential of a portion on the wiring board where the conductive fine particles are not desired to be attached, the conductive fine particles can be prevented from being attached to the vicinity of that portion.

[Brief description of drawings]

1 (a) and 1 (b) are schematic views showing a method for spraying conductive fine particles according to an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are other embodiments of the present invention. FIG. 3 is a schematic view showing a method for spraying conductive fine particles according to the present invention, FIG. 3 and FIG. 4 are schematic views showing a method for spraying conductive fine particles according to still another embodiment of the present invention, and FIG. It is a schematic diagram which shows the spraying method of the electroconductive fine particles which concerns on the basic Example of invention. 1: Corona charging pin, 2: High voltage power supply, 3a: Negative ion, 3
b: Free ion, 4: Electrode terminal of wiring board, 5: Insulator, 6:
Wiring board base board, 7: flat plate electrode, 13: ground wire, 9:
Spray gun, 10a: conductive particles before charging, 10b: charged conductive particles, 10c: conductive particles deposited on the electrode terminals,
11: Electric lines of force, 12: Electrode pattern, 3c: Free ions, 8a:
Ground wire, 13, 14: power supply, 10d: conductive fine particles.

Claims (4)

[Claims] 1. An electrostatic field in which an electric field is concentrated on a first electrode terminal provided on the surface of a substrate, in which electrostatically charged conductive fine particles are sprayed to selectively select the first electrode terminal on the first electrode terminal. A method for interconnecting electrode terminals, comprising providing conductive particles and then connecting second electrode terminals to the first electrode terminals through the conductive particles. 2. The method of interconnecting electrode terminals according to claim 1, further comprising the step of charging the surface of the substrate other than the first electrode terminals to a potential having the same polarity as the charging potential of the conductive fine particles. 3. The electrode terminal according to claim 2, wherein the electric field is concentrated on the first electrode terminal by holding the first electrode terminal at a ground potential or a potential having a polarity opposite to the charging potential of the conductive fine particles. Interconnection method. 4. The electrified conductive fine particles are sprayed in an electrostatic field in which an electric field is concentrated on the first electrode terminals provided on the surface of the substrate, so that the first electrode terminals are selectively electrified on the first electrode terminals. A method of manufacturing an electrical connection structure, comprising applying conductive fine particles and then connecting a second electrode terminal to the first electrode terminal through the conductive fine particles.