Method of manufacturing semiconductor device

A method of manufacturing a semiconductor device comprising the steps of:

• (a) providing a lead frame having
• (x1) a frame part having a substantially rectangular frame-like portion,
• (x2) a tie-bar having a substantially rectangular frame-like portion, wherein the tie-bar is supported by the frame part, and formed inside therefrom,
• (x3) a plurality of leads extending inward and outward from each of four sides of the tie-bar,
• (x4) a die pad formed inside from the tie-bar, and having first and second principal faces,
• (x5) a die-pad-support lead extending inward from each corner part of the tie-bar or a joint part near the corner part, and joined to the die pad, and
• (x6) a down-set part formed in each die-pad-support lead so as to set down the die pad on the side of the second principal face;
• (b) bonding a semiconductor chip to the first principal face of the die pad via an adhesive-member layer;
• (c) after the step (b), setting the lead frame between a first molding die having a first cavity and a second molding die having a second cavity such that the first and second cavities are opposed to each other, and such that the second principal face of the die pad faces toward the second cavity;
• and
• (d) forming first and second resin sealed bodies on the sides of the first and second principal faces of the die pad respectively by performing resin sealing while the first and second molding dies clamping the tie-bar and a part of the lead frame located around the tie-bar,
• wherein a clamp-face concaved part is formed in a part of the first or second molding die corresponding to the joint part.