| 摘要 |
PROBLEM TO BE SOLVED: To provide Pb-free solder connected structures and electronic devices in which sufficient connection strength, stable interfaces over time, sufficient solder wettability, and whisker-free characteristics are secured. SOLUTION: In this invention, an Sn-Ag-Bi based solder which has a great potential for a Pb-free solder is used in the connection with an electrode on the surface of which an Sn-Bi based layer is deposited. Preferably, the concentration of the Bi in the Sn-Bi layer is 1 to 20 wt.% for the sufficient wettability. In the case where a joint of high reliability is required, a Cu layer is deposited under the Sn-Bi layer to provide n a connection of sufficient interface strength. COPYRIGHT: (C)2010,JPO&INPIT |
