| 摘要 |
PURPOSE:To prevent the deformation of lead and the deterioration of semiconductor elements because of no large impact at the time of cutting in the lead frame providing the dam for supporting the intermediate part of the lead with an external frame by forming said dam is such a manner that the width thereof becomes narrower in the area coming close to the cutting end. CONSTITUTION:A dam 50 is formed almost in a diamond shape in such a manner that the width becomes narrower in the area coming close to the cutting end as the width of central part is indicated by B, while the width of cutting end is indicated by (b). Thereby, the dam can be efficiently cut with a small size cutting device resulting in small cutting impact. |
