Abstract: A semiconductor device is provided with a heat dissipating face side skirt portion, which is a frame-form projection, on a heat dissipating face of a lead frame. Because of this, creepage distance increases with a small increase in an amount of resin, and insulating properties improve. Also, the heat dissipating face side skirt portion is molded via two transfer molding steps, wettability of the second molding resin with respect to a first molding resin and the lead frame increases, and adhesion improves. Furthermore, an end face of an inner lead is exposed in an element sealing portion on a mounting face side, and covered with a second thin molded portion molded using the second molding resin, whereby heat generated in a semiconductor element can efficiently be caused to escape from faces of both a first thin molded portion and the second thin molded portion, because of which heat dissipation improves.

Abstract: A power semiconductor device is such that a notch provided, along a longitudinal end face of an inner lead, in a region of a lead frame to which the inner lead is bonded. A resistor is disposed, adjacent to the inner lead, on the same side as the notch with respect to the inner lead, and a distance between the inner lead and the notch is set to be smaller than a distance between the inner lead and the resistor, and thereby the inner lead, even when shifted in position, comes into no contact with the resistor. Because of this, it is no more necessary that a space be provided around the inner lead taking into consideration a positional shift of the inner lead, and it is possible to secure the heat release area of power semiconductor chips accordingly, and thus to obtain the small-sized and high-powered power semiconductor device.

Abstract: A semiconductor device is provided with a heat dissipating face side skirt portion, which is a frame-form projection, on a heat dissipating face of a lead frame. Because of this, creepage distance increases with a small increase in an amount of resin, and insulating properties improve. Also, the heat dissipating face side skirt portion is molded via two transfer molding steps, wettability of the second molding resin with respect to a first molding resin and the lead frame increases, and adhesion improves. Furthermore, an end face of an inner lead is exposed in an element sealing portion on a mounting face side, and covered with a second thin molded portion molded using the second molding resin, whereby heat generated in a semiconductor element can efficiently be caused to escape from faces of both a first thin molded portion and the second thin molded portion, because of which heat dissipation improves.

Abstract: A power semiconductor device is such that a notch provided, along a longitudinal end face of an inner lead, in a region of a lead frame to which the inner lead is bonded. A resistor is disposed, adjacent to the inner lead, on the same side as the notch with respect to the inner lead, and a distance between the inner lead and the notch is set to be smaller than a distance between the inner lead and the resistor, and thereby the inner lead, even when shifted in position, comes into no contact with the resistor. Because of this, it is no more necessary that a space be provided around the inner lead taking into consideration a positional shift of the inner lead, and it is possible to secure the heat release area of power semiconductor chips accordingly, and thus to obtain the small-sized and high-powered power semiconductor device.