| 摘要 |
A circuit board (A 1 ) includes an insulative substrate ( 1 ), a conductive pad ( 4 a) formed on the substrate, and a metal ( 3 ) bonded to the pad via a solder layer ( 6 ). The metal piece ( 3 ) has a welding portion ( 3 a) to which an external-connection terminal ( 5 ) is welded. A gap ( 7 ) is provided between the welding portion ( 3 a) and the substrate ( 1 ). The welding portion ( 3 a) and the solder layer ( 6 ) are separated by the gap ( 7 ). |
