UNDERFILL MATERIAL AND METHOD FOR MOUNTING ELECTRONIC COMPONENT

摘要

In flip chip mounting of an electronic component, an underfill is filled between the component and a substrate, thereby reducing the thermal stress or the like. In conventional mounting of an electronic component using a copper pillar, there is such a problem that a filler contained in an underfill is separated during a heat curing step of a resin. In the present invention, the surface of a copper pillar is plated with a solder. Consequently, a movement of the charged filler in the underfill, which is caused by the electric field that is formed by a local battery due to a contact between different metals, can be prevented, thereby preventing occurrence of cracks in a connection part. As a result, the connection reliability can be improved.