| 摘要 |
<p>PURPOSE:To make it hard to develop any crack in a resin mold layer or make such a crack develop only in a specific part even if it develops by forming a protrusion on the rear of an island part of a lead frame. CONSTITUTION:After mounting a semiconductor chip 3 on an island part 7 having a protrusion 6 of a lead frame 1, for example, by soldering, chip and lead frame terminals are connected with a wire 4. After that, a resin mold layer 5 is formed with an epoxy resin and the like. In such a case, the relationship between the thickness of its layer 5 and the length of its protrusion 6 is determined so that the protrusion makes its way through the inside of the resin mold layer 5. Such a length of the protrusion 6 makes it possible to develop a crack from a pointed end part of the protrusion 6 to the outside of the above layer 5 when stress becomes high at the inside of a semiconductor device and then it eventually lowers inner stress to prevent the expansion of cracks. Usually, most of cracks develop when its device is mounted and then, even if fine cracks develop, the cracks are filled with soldering immediately.</p> |
