| 摘要 |
PROBLEM TO BE SOLVED: To provide a lead-free high-temperature solder material as an alternative material for the conventional high-temperature lead-tin solder. SOLUTION: When copper grains are added to a solder alloy composed of bismuth-copper-germanium, thus an electronic component and a semiconductor device or the like in a module component are reflow-mounted with a module substrate, and thereafter the module component is further reflow-mounted on a mother board, a joining material is not remelted by heat upon the reflow-mounting. The joining material is composed of: solder balls consisting of, by weight, 0.2 to 0.8% copper, 0.02 to 0.2% germanium and 69 to 84.78% bismuth; and 15 to 30% copper grains. COPYRIGHT: (C)2008,JPO&INPIT |
