| 摘要 |
There are provided a method of soldering a lead-free solder which lowers a melting point of the lead-free solder and prevents deterioration of a joining strength at a portion joined by the lead-free solder, and a joined object soldered with the use of the soldering method. The lead-free solder as an alloy of tin with no lead contained is melted, and ultrasonic vibration is acted at least either to the join object to be joined by the lead-free solder or to the lead-free solder when the molten lead-free solder is solidified. Therefore crystals of contained components in the lead-free solder are made fine and the contained components are prevented from being segregated at a joining interface of the joined object, so that the joining strength at the joining interface can be increased. <IMAGE> |
