Lead frame, resin-encapsulated semiconductor device and fabrication process therefor

摘要

In a resin-encapsulated semiconductor device in which a semiconductor element is placed on the front surface of a die pad (23) of a lead frame (2) including the die pad (23) and support bars (24) of the die pad (23) that protrude outwardly from sides of the die pad (23), the semiconductor element and its periphery are encapsulated with a resin material while the rear surface of the die pad (23) is exposed to the external environment. A groove (27) is formed on the rear surface of the support bar (24) so that the groove (27) traverses the support bar (24) in the neighborhood of the boundary between the support bar (24) and the die pad (23) along a direction intersecting a protruding direction of the support bar (24). The groove (27) may be formed on the front surface of a support bar (24). The invention enables fabrication of a semiconductor device with an improved level of exposure of the rear surface of a die pad, so that deformation of the die pad in a resin-encapsulating step is prevented from occurring and the device can be mounted on a printed wiring board with a sufficient soldering strength.