Lead frame having oblique slits on a die pad

Abstract

A lead frame has a frame section for carriage, a square die pad for mounting a semiconductor chip, and four suspension arms bridging the frame section and corners of the die pad. The die pad has a plurality of oblique slits therein extending parallel to one another and parallel to a diagonal line of the die pad passing first and second corners of the die pad. During encapsulation, resin is introduced from a gate of molding dies located at the first corner to a vent of the molding dies located at the second corner. The oblique slits enhances oblique resin-flow under the lower surface of the die pad during encapsulation of the semiconductor device, to thereby prevent a die pad shift, unfilling of the resin and resin void in the semiconductor device.

Dependencies are inferred from the claim text.