| 摘要 |
PROBLEM TO BE SOLVED: To connect an electronic component, with high reliability, to a conventional circuit board employing Pb free solder in place of Sn-37Pb solder. SOLUTION: Solder pastes 4a-4d being fed onto wiring patterns 3a-3d of a circuit board 1 has V-shape, recessed shape or projecting shape on the inner side. |
