Lead frame used for the fabrication of semiconductor packages and semiconductor package fabricated using the same

Abstract

A lead frame for a semiconductor package including a rectangular lead frame body having a central opening, a plurality of leads arranged at and along each of two or four facing sides of the lead frame body, the leads extending in flush with the lead frame body, and a semiconductor chip mounting plate positioned on a plane not flush with a plane, where the leads are positioned, the semiconductor chip mounting plate being supported by down-set tie bars and provided with at least one groove having a rectangular ring shape while serving to prevent a penetration of moisture and to provide an increased coupling strength for the semiconductor chip mounting plate, the semiconductor chip mounting plate also serving as a heat sink. A ground bridge bar having a rectangular ring shape is arranged between the semiconductor chip mounting plate and the leads and supported by another tie bars. By virtue of the bridge bar, the length of bonding wires is reduced, thereby eliminating the possibility of the bonding wires to be short-circuited. A lead frame having a double down-set structure is also provided. By virtue of the double down-set structure, it is possible to increase the size of the semiconductor chip mounting plate, thereby achieving an improvement in the heat discharge effect.