Bump electrode, board which has bump electrodes, and method for manufacturing the board

Patent metadata

Field	Value
Publication number	US-9662730-B2
Application number	US-201414475249-A
Country	US
Kind code	B2
Filing date	Sep 2, 2014
Priority date	Sep 3, 2013
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

A bump electrode is formed on an electrode pad using a Cu core ball in which a core material is covered with solder plating, and a board which has bump electrodes such as semiconductor chip or printed circuit board mounts such a bump electrode. Flux is coated on a substrate and the bump electrodes are then mounted on the electrode pad. In a step of heating the electrode pad and the Cu core ball to melt the solder plating, a heating rate of the substrate is set to have not less than 0.01° C./sec and less than 0.3.

First claim

What is claimed is:

1. A method for making a bump electrode on an electrode pad, the bump electrode being made from a core ball covered with solder plating, comprising the steps of:
providing an electrode pad;
mounting the core ball covered with solder plating on the electrode pad; and
heating the electrode pad and thereby melting the solder plating in a reflow process wherein a heating rate is such as to raise a temperature of the electrode pad during the reflow process not less than 0.01 degrees C./second and less than 0.3 degrees C./second in the heating and melting step while heating in the temperature range from 210° C. to 230° C.

2. A method for manufacturing a board which has a bump electrode, the method comprising the steps of:
providing an electrode pad on a substrate;
mounting a connecting member, the connecting member including a core ball covered with solder plating, on the electrode pad; and
heating the substrate and thereby melting the solder plating with which the core ball is covered, while controlling a rate of heating the substrate and thereby raising the temperature of the electrode pad during a reflow process by not less than 0.01° C./sec but less than 0.3° C./sec in the step of melting the solder plating while heating in the temperature range from 210° C. to 230° C.).

Assignees

• Senju Metal Industry Co

Inventors

• Hattori Takahiro
• Soma Daisuke
• Sato Isamu

Classifications

• H10W95/00

  Packaging processes not covered by the other groups of this subclass · CPC title

• H10W72/01257

  by reflowing · CPC title

• H10W72/01225

  in solid form, e.g. by using a powder or by stud bumping · CPC title

• H10W72/01212

  at a different location than on the final device, e.g. forming as prepeg · CPC title

• H10W72/255

  of outermost layers of multilayered bumps, e.g. material of a coating · CPC title