Semiconductor device and manufacturing method thereof

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

• (a) preparing a lead frame including a chip mounting portion and a first lead portion;
• (b) after the step (a), mounting a semiconductor chip having a first main surface, a first electrode formed in the first main surface, and a second main surface opposite to the first main surface, over the chip mounting portion of the lead frame via a bonding material such that the second main surface is opposed to the chip mounting portion;
• (c) after the step (b), arranging a metal plate over the first electrode of the semiconductor chip via a first solder, and over the first lead portion via a second solder;
• (d) after the step (c), bonding the metal plate to the first electrode of the semiconductor chip via the first solder, and to the first lead portion via the second solder, by a heat treatment for melting the first solder and the second solder;
• and
• (e) after the step (d), forming a sealing member for covering a part of the chip mounting portion, a part of the first lead portion, the semiconductor chip, and the metal plate,
• wherein a softening temperature of the metal plate used in the step (c) is lower than a softening temperature of the lead frame prepared in the step (a).

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

• (a) preparing a lead frame including a chip mounting portion and a first lead portion;
• (b) after the step (a), mounting a semiconductor chip having a first main surface, a first electrode formed in the first main surface, and a second main surface opposite to the first main surface, over the chip mounting portion of the lead frame via a bonding material such that the second main surface is opposed to the chip mounting portion;
• (c) after the step (b), arranging a metal plate over the first electrode of the semiconductor chip via a first solder, and over the first lead portion via a second solder;
• (d) after the step (c), bonding the metal plate to the first electrode of the semiconductor chip via the first solder, and to the first lead portion via the second solder, by a heat treatment for melting the first solder and the second solder;
• and
• (e) after the step (d), forming a sealing member for covering a part of the chip mounting portion, a part of the first lead portion, the semiconductor chip, and the metal plate,
• wherein a rate of decrease in hardness of the metal plate by the heat treatment in the step (d) is larger than a rate of decrease in hardness of the lead frame by the heat treatment in the step (d).