Method for connecting printed circuit boards

Abstract

To provide a method for connecting printed circuit boards with high connection reliability, while avoiding the problem of shorting even with a fine pitch. A method for connecting printed circuit boards (PCB) containing metal wiring, or connecting a printed circuit board (PCB) containing metal wiring with a metal lead wire or a metal contact, which method includes a step of thermocompression bonding of an adhesive film with connectors, the adhesive film being composed of an adhesive composition comprising a thermoplastic resin and organic particles, wherein the viscosity decreases as the applied thermocompression force increases at a temperature of 100-250 DEG C.

Description

technical field [0001] The present invention relates to a method for connecting a printed circuit board (PCB) containing metal wiring (including flexible type and rigid type) or connecting a printed circuit board (PCB) containing metal wiring with metal leads or metal contacts (for example, in electrical Metal contacts in connectors) method. Background technique [0002] Methods utilizing soldering, anisotropic conductive adhesives, and mechanical connectors have been used in the past as electrical connection techniques for establishing connections between circuit boards. Soldering requires temperatures of 260°C and higher, and the surrounding assembled parts and even the circuit board itself sometimes cannot withstand such high temperatures. The assembly order and assembly position of parts must be considered so that parts with low thermal resistance are not exposed to heat, and this has reduced assembly density and limited the kinds of parts that can be assembled. Format...

AI Technical Summary

Problems solved by technology

Anisotropic conductive adhesives provide continuity through conductive particles in the resin, but their high connection resistance has been a problem

In addition, this method is inconvenient because breaking continuity to repair requires organic solvents, etc.

Conventional mechanical connectors, on the other hand, are helpful for repairs, but have similar problems as soldering, since the assembly of the connector itself must use soldering

In addition, especially in the case of mechanical connectors, since they have a mechanical structure that allows connection, the connector itself must have a certain size that is not conducive to high-density assembly and thin-profile assembly, so that high-density 0.3mm or smaller pitch Fitting and thin connection of 0.8mm or less cannot be achieved

[0003] Japanese Unexamined Patent Publication (Kokai No. 62-184788) describes a method in which a connection is made by passing a pair of opposing conductors through an insulating adhesive, but this technique does not provide "plastic flow characteristics" (at this property the viscosity of the adhesive only drops when high stresses are applied), and it is not suitable for easy repair

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