| 摘要 |
PROBLEM TO BE SOLVED: To provide a solder joint forming method capable of enhancing initial joint strength in solder joint, and of securely solder joining electronic devices or the like. SOLUTION: An electronic device mounting substrate 1 includes a substrate 2, an electrode layer 4 formed on the substrate, and a solder layer 5 formed on the electrode layer. The solder joint is formed beforehand by applying heat treatment at a low heat treatment temperature lower than a melting point of the solder layer 5 to the electronic device mounting substrate 1, where an electronic device is joined with the solder layer 5. The initial joint strength can be made≥30 MPa as an equilibrium state by heat treating a solder constituting the solder layer 5 after the solder junction of the electronic device. Failure soldering of the electronic device is reduced to improve the yield in the electronic device mounting. COPYRIGHT: (C)2007,JPO&INPIT |
