| 摘要 |
<p>PROBLEM TO BE SOLVED: To effectively transmit heat which is generated from an electronic part itself into air, without using a radiation member and the like in a plastic package. SOLUTION: Dimples are formed on the whole surface/back of an IC package at uniform intervals, and radiation is improved by the increase of a surface area. In metallic molds (an upper mold 201 and a lower mold 202) in transfer molding, pins 203 which can move vertically for working the dimples (ruggedness processing) are generated for parts, equivalent to the surface and the back of the plastic package on the whole face, so that the respective pin arrangements become the uniform intervals. In a stage prior to the molding metallic molds release, the pins for dimple work in the upper mold operate downwards from the upper part, and the pins for dimple work in the lower mold similarly operate upwards from the lower part. Molding resin which is not completely hardened yet is compressed by the respective pins. Thus, the uniform dimple marks (ruggedness) 401 (final form sections) are formed on the surface and the back of the plastic package.</p> |
