摘要 |
<p>A Pb-free solder-connected structure having a sufficiently large connection strength, featuring an interface that remains stable even after the passage of time, and maintaining sufficient wettability and resistance against whiskers, and an electronic device. Specifically, a Pb-free solder, characterized in that an Sn-Ag-Bi solder which is a representative Pb-free solder is connected to an electrode that has an Sn-Bi layer formed on the surface thereof. Bi concentration in the Sb-Bi layer is preferably 1 to 20 % by weight to obtain a sufficient degree of wettability. When a more reliable joint is required, the Cu layer is formed under the Sn-Bi layer to obtain a connection portion having a sufficiently large interfacial strength.</p> |
申请人 |
HITACHI, LTD.;SHIMOKAWA, HANAE;SOGA, TASAO;OKUDAIRA, HIROAKI;ISHIDA, TOSHIHARU;NAKATSUKA, TETSUYA;INABA, YOSHIHARU;NISHIMURA, ASAO |
发明人 |
SHIMOKAWA, HANAE;SOGA, TASAO;OKUDAIRA, HIROAKI;ISHIDA, TOSHIHARU;NAKATSUKA, TETSUYA;INABA, YOSHIHARU;NISHIMURA, ASAO |