| 摘要 |
PROBLEM TO BE SOLVED: To provide electronic equipment by a new soldered connection, and in particular to achieve a soldered connection at a high temperature side in the connection using a temperature hierarchy. SOLUTION: A connected part of a semiconductor device and a substrate is formed by reflowing solder paste, comprising metal balls 1 of Cu and compounds 2, 5 of the metal ball and Sn, at a temperature of 250 deg.C or higher. The metal balls 1 are coupled with the compound 3 by this reflow. As a result, lead-free soldering can be supported, and a first reflow at a high temperature side of <=290 deg.C that does not exceed the heat resistance of components in module mounting and a further second reflow on a printed board with a low temperature solder in surface mounting are made possible. |
