| 摘要 |
PROBLEM TO BE SOLVED: To provide Pb-free solder paste which has high temperature stability that electronic parts do not fall or move even in the secondary soldering, to provide electronic parts, and to provide a step soldering method. SOLUTION: The metal powder of the solder paste consists of 30 to 90 mass% intermetallic compound powder of Sn, and the balance Sn powder or Pb-free solder powder essentially consisting of Sn. The soldering part of the electronic parts is soldered with the solder paste. In the step soldering, the solder paste is used for the first soldering, and Pb-free solder is used for the secondary soldering. COPYRIGHT: (C)2004,JPO |
