| 摘要 |
PURPOSE:To facilitate absorbing stress caused by sudden thermal shock at the time of surface mount of a semiconductor device and reduce defects of the semiconductor devices by softening a lead frame to have a predetermined hardness. CONSTITUTION:A lead frame 1 for surface mounting of a semiconductor device is prepared and the lead frame 1 is softened to have a predetermined hardness. Then a semiconductor element is mounted on the lead frame 1 and the semiconductor element on the lead frame 1 is sealed with resin. Further, the semiconductor device 3 is put on a printed board 4 and fixed to the printed board 4 by heating in a solder reflow furnace. As the lead frame 1 for surface mounting is softened to have the predetermined hardness after the lead frame 1 is prepared, a gap between the resin and the lead frame 1 created by sudden thermal shock is avoided so that, even if surface mount is carried out by the solder reflow furnace, the defects can be reduced owing to excellent adhesiveness.
|
