摘要 |
A solder paste whereby metal does not flow out of a joint during a second or subsequent reflow heating stage. Said solder paste exhibits high joint strength at room temperature and at high temperatures, excels in terms of temporal stability, exhibits minimal void formation, and can form highly cohesive joints. Said solder paste comprises a powdered metal component and a flux component, said powdered metal component comprising the following: a powdered intermetallic compound that comprises copper and tin and has metal barrier layers covering the surfaces thereof; and a solder powder consisting primarily of tin. Neither the powdered intermetallic compound nor the solder powder contains a copper-only phase, inhibiting the elution of copper ions into the flux. |