JPH0362536A - Method for interconnecting electrode terminals and manufacturing method for electrical connection structure - 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 [Industrial Application Field] The present invention provides a wiring board for electrically interconnecting electrode terminals of a wiring board facing another wiring board etc. via conductive fine particles. The present invention relates to a method of dispersing conductive fine particles onto a surface.

[Prior Art] Conventionally, in order to electrically interconnect electrode terminals of opposing wiring boards via conductive fine particles, a method of dispersing conductive fine particles onto a wiring board is shown in FIG. To,
A method of charging conductive fine particles 10a by passing them through a corona electric field created by a corona discharge electrode 1, and scattering the charged conductive fine particles 10b on an electrode terminal 4 of a wiring board in an electrostatic field where the electric field is concentrated. is used.

[Problem to be solved by the invention] However, in the conventional method for dispersing conductive particles,
There were a considerable number of conductive fine particles 10d that adhered to areas on the wiring board where conductive fine particles were not required, and the insulation resistance between the wirings on the wiring board could be lowered.

Furthermore, particularly when semiconductor elements are connected face-down on a wiring board, if conductive particles are present in a portion of the semiconductor element corresponding to the die edge portion, edge shorts may occur.

In addition, in wiring boards that are connected facing each other, if particles are present in a part that is narrower than the gap between the electrodes that are connected facing each other, it is possible to bring the facing electrode terminals closer together and sandwich the conductive fine particles. There were times when it caused problems.

In view of the problems of the prior art, an object of the present invention is to
In a method for dispersing conductive fine particles, it is an object of the present invention to enable conductive fine particles to be dispersed only to necessary portions on a wiring board.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides electrically charged conductive fine particles on electrode terminals of a wiring board that is electrically connected to a connecting portion of another wiring board or a component. In the method of dispersing in an electrostatic field where the electric field concentrates on the electrode terminal, a potential of the same polarity as the charged potential of the conductive fine particles is applied to a portion of the wiring board where the conductive fine particles are not desired to adhere. There is.

Here, as a method of imparting a potential of the same polarity as the charged potential of the conductive particles to a part on the wiring board where it is not desired that the conductive particles adhere, the part is made of an insulator made of a dielectric material, and by corona discharge etc. There is a method in which the generated free ions are attached to the surface of an insulator. Alternatively, there is a method of providing an electrode pattern at that part and applying a potential.

Further, the electrode terminal may be applied with a ground potential or a potential with a polarity opposite to the charged potential of the conductive fine particles.

[Function] In this configuration, the charged conductive fine particles are scattered in an electrostatic field where the electric field is concentrated on the electrode terminal, but the charged conductive fine particles are scattered in areas on the wiring board where the conductive fine particles are not desired to adhere. Because the electrical potential is made to have the same polarity as the potential, electrostatic stress acts between this area and the conductive particles, and the conductive particles may adhere to areas on the wiring board where they are not needed. Avoided.

[Example] Hereinafter, the present invention will be explained in detail using the drawings.

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

In the same figure, 1 indicates conductive fine particles 10 due to corona discharge.
Corona charging pin (corona discharge electrode) for charging a
, 2 is a high-voltage power supply for applying voltage to the corona charging pin 1, 4 is an electrode (terminal) of the wiring board, 6 is the base board of the wiring board, 7 is a flat plate electrode (electrode plate), and 13 is the flat plate electrode 7. A ground wire 9 is used to bring the conductive particles to the corona charging pin, and 8a is a ground wire used to bring the electrode terminals of the wiring board to the earth potential.

In order to scatter conductive particles onto the wiring board in this configuration, first, as shown in FIG. A wiring board is placed between the corona discharge electrode 1 and the electrode plate 7 grounded to earth potential, and free ions (negative ions) 3a generated from the corona discharge electrode 1 are transferred onto the insulating film 5. to charge the insulating film 5.

Thereafter, as shown in FIG. 1(b), conductive fine particles 10
a is passed through a corona electric field created by a corona discharge electrode 1 and charged. As a result, the charged conductive fine particles 10b are placed in an electrostatic electric field created between the discharge electrode 1 and the lead-out electrode 4 of the wiring board, which is given a ground potential or a potential of opposite polarity to the charged potential of the conductive fine particles. electric field lines 1
1 and attached to the connection part of the extraction electrode 4.

At this time, since the surface of the insulating film 5 is charged to the same polarity potential as the charged fine particles 10b, the charged fine particles tab are repelled by the electrostatic stress against the insulating film 5, and the conductive fine particles are moved onto the insulating film 5. can be avoided from adhering to.

FIGS. 2(a) and 2(b) illustrate a method according to another embodiment of the invention. In this method, first, an electrode pattern 12 is provided on the wiring board in order to give a potential of the same polarity as the charged potential of the conductive particles to a region on the wiring board where it is not desired that the conductive particles adhere. in the same way as above,
It is charged to the same polarity as the charged potential of the conductive fine particles to be dispersed.

Thereafter, as shown in FIG. 2(b), the conductive fine particles 10a are charged and dispersed in an electrostatic field in the same manner as described above. At this time, since the electrode pattern 12 is charged with the same polarity as the charged potential of the conductive fine particles, the charged conductive fine particles 10b are repelled by the electrostatic stress of the electrode pattern 12, and the conductive fine particles are moved onto the electrode pattern. can be avoided from adhering to.

FIG. 3 shows yet another embodiment. In order to give a potential of the same polarity as the charged potential of the conductive particles to a region on the wiring board where it is not desired that the conductive particles adhere, the electrode pattern 12 is provided in that region, but here A potential is applied to the electrode pattern 12 by the power source 14, and the conductive fine particles are then charged and dispersed in an electrostatic field in the same manner as described above. At this time, since the electrode pattern 12 is given a potential of the same polarity as the charged potential of the conductive fine particles 10b, the charged conductive fine particles tab are
2, the conductive fine particles ta are repelled by electrostatic stress.
b can be prevented from adhering to the electrode pattern 12.

Furthermore, as shown in FIG. 4, electrode terminals 4 on the wiring board
The power supply 8a may apply a potential of opposite polarity to the charged potential of the conductive fine particles tab, thereby increasing the electrostatic attraction between the charged conductive fine particles 10b and the electrode terminal 4, as shown in FIG. 3(a). ) The conductive fine particles can be easily attached onto the electrode terminals.

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

That is, by applying a potential of the same polarity as the charged potential of the conductive particles to a portion of the wiring board where it is not desired that the conductive particles adhere, electrostatic stress is exerted between this portion and the conductive particles. , it is possible to avoid adhesion of conductive fine particles to areas on the wiring board that do not require conductive fine particles.

This prevents conductive particles from adhering to areas other than the electrode terminals of the wiring board that are connected facing each other. physical interconnection.

Furthermore, when electrical connection is made using conductive particles to connect semiconductor elements face-down on a wiring board, the conductive particles may adhere to the portions of the wiring board that correspond to the die edges of the semiconductor elements. can be avoided,
It is possible to prevent edge shorts between the wiring board and the semiconductor element.

Furthermore, when electrically interconnecting wiring boards facing each other using conductive fine particles, it is important to avoid adhesion of the conductive fine particles to areas that are narrower than the gap between electrode terminals that are connected facing each other. Therefore, when connecting wiring boards by crimping, it is possible to narrow the gap between opposing electrode terminals and sandwich the conductive fine particles without any problem.

Furthermore, by increasing the potential of a portion of the wiring board where the attachment of conductive fine particles is not desired, adhesion of conductive fine particles to the vicinity of that portion can be avoided.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are schematic diagrams showing a method of dispersing conductive fine particles according to one embodiment of the present invention, and FIGS. 2(a) and (b) are other embodiments of the present invention. FIG. 3 and FIG. 4 are schematic diagrams showing a method of dispersing conductive fine particles according to still another embodiment of the present invention, and FIG. FIG. 2 is a schematic diagram showing a method of dispersing conductive fine particles according to an example. 1: corona; wit pin, 2: high voltage power supply, 3a: V inus ion, 3b: free ion, 4: electrode terminal of wiring board, 5: insulator, 6: base board of wiring board, 7: flat plate electrode, 13: Earth wire, 9: Spray gun, 10a: Conductive fine particles before charging, 101) = Charged conductive fine particles, 1
0c: N, conductive fine particles attached to the Fix terminal, 11
: electric force lines, 12: electrode pattern, 3c: free ions, 8a: ground wire, 13, 14: power supply, 10d: conductive fine particles. Figure Figure Figure Figure

Claims (3)

[Claims] (1) Spray charged conductive fine particles onto the electrode terminal of a wiring board that is electrically connected to the connection part of another wiring board or component in an electrostatic field that concentrates the electric field on the electrode terminal. A method for dispersing conductive fine particles, the method comprising applying a potential of the same polarity as the charged potential of the conductive fine particles to a portion of the wiring board where the conductive fine particles are not desired to adhere. (2) The method for dispersing conductive fine particles according to claim 1, wherein the electrode pattern is provided at a portion of the wiring board where attachment of the conductive fine particles is not desired. (3) The method for dispersing conductive fine particles according to claim 1, wherein the electrode terminal is given a ground potential or a potential of opposite polarity to the charged potential of the conductive fine particles.