To solve the problem that outer leads are deformed and chipped off in the deburring process because burrs produced between outer leads in a resin-sealing metal mold do not protrude from the outer lead mount surface.

In the region where outer leads 7 are exposed in this resin sealing metal mold 1, recesses 20 are provided in the lower metal 3, for instance, corresponding to the region in the upper metal 2 where dam clearances 12 are formed. In the process of resin molding in this metal mold designed as such, both dam clearances 8 and recesses 20 are also filled up with resin flowing out of the cavity 13, and the resin grows into dam burrs when cured. As the result, burs thus formed protrude from the mount surface of the outer leads 7 after release of the resin sealing metal mold 1, the protrusions of the dam burrs are removed by pressing, and this prevents the outer leads 7 from deformation or the like.

COPYRIGHT: (C)2004,JPO