Semiconductor device and manufacturing method of semiconductor device
A semiconductor device that improves noise performance includes a circuit substrate, an enclosing case, and a metal part. A control circuit is mounted on the front surface of the circuit substrate. The enclosing case is a resin case in which semiconductor elements are installed. The metal part, included inside the enclosing case, includes a first mounting portion, a second mounting portion, and a bus bar. The first mounting portion mounts the circuit substrate on the enclosing case, and is connected to a ground pattern of the circuit substrate when mounting. The second mounting portion mounts an external instrument on the enclosing case, and is grounded when mounting. The bus bar connects the first mounting portion and second mounting portion.
1. A semiconductor device, comprising:
an enclosing case in which semiconductor elements are installed;
a circuit substrate on which a control circuit is mounted; and
a metal part, having a first mounting portion which mounts the circuit substrate on the enclosing case and is connected to a ground pattern of the circuit substrate when mounting, and a second mounting portion which mounts an external instrument on the enclosing case and is grounded when mounting, which connects the first mounting portion and second mounting portion, the metal part comprising a bus bar positioned to be parallel to the circuit substrate and having a first end and a second end opposite from the first end, wherein the first mounting portion is positioned on the first end and comprises an opening in which a first screw can be inserted, and the second mounting portion is positioned on the second end and comprises an opening in which a second screw can be inserted.
2. The semiconductor device according to claim 1 , wherein the metal part comprises:
a metal columnar support which is the first mounting portion which forms a screw seat for fastening, fixing, and mounting the circuit substrate to the enclosing case with the first screw and is connected to the ground pattern of the circuit substrate;
a metal ring portion which is the second mounting portion which forms a screw seat for fastening, fixing, and mounting the external instrument to the enclosing case with the second screw and is grounded through the second screw protruding outside the enclosing case; and
a metal bus bar which is the bus bar which connects the metal columnar support and ring portion.
3. The semiconductor device according to claim 2 , wherein the external instrument is a cooling fin which is fastened and fixed to the enclosing case by the second screw protruding outside the enclosing case, and the ground pattern of the circuit substrate is electrically connected to a metal surface of the cooling fin via the metal part.
4. The semiconductor device according to claim 2 , wherein the external instrument is a housing which is fastened and fixed to the enclosing case by the second screw protruding outside the enclosing case, and the ground pattern of the circuit substrate is electrically connected to the metal surface of the housing via the metal part.
5. The semiconductor device according to claim 2 , wherein the metal columnar support, ring portion, and metal bus bar are individual parts, and one end of the metal bus bar is fixed to a protruding portion provided at the leading end of the metal columnar support, while the other end of the metal bus bar is fastened and fixed to the ring portion by the second screw.
6. The semiconductor device according to claim 2 , wherein the metal columnar support, ring portion, and metal bus bar are integrally molded into one part.
7. The semiconductor device according to claim 2 , wherein either the metal columnar support and metal bus bar are integrally molded into one part or the metal bus bar and ring portion are integrally molded into one part.
8. The semiconductor device according to claim 1 , wherein a metal component is provided on at least one of the four corners of the enclosing case.
9. The semiconductor device according to claim 1 , further comprising a heat dissipation board arranged on a bottom portion of the enclosing case.
10. The semiconductor device according to claim 9 , wherein an inside part of the enclosing case includes a ring portion which connects the enclosing case and the heat dissipation board.
11. The semiconductor device according to claim 1 , further comprising a heat dissipation board disposed between the enclosing case and the external instrument, the external instrument being fastened to the enclosing case by the second screw inserted in the opening of the second mounting portion.
12. The semiconductor device according to claim 1 , wherein the first mounting portion, the second mounting portion, the bus bar, and the external instrument are electrically connected to each other.
13. The semiconductor device according to claim 1 , wherein the second screw inserted in the opening of the second mounting portion penetrates a surface of the external instrument.