Semiconductor module and electrically-driven vehicle
A semiconductor module includes a first semiconductor element, a second semiconductor element, a first heat spreader electrically and thermally connected to the first semiconductor element, a second heat spreader electrically and thermally connected to the second semiconductor element, a DCB substrate including a first metal foil on a top surface of a ceramic insulating substrate and including a second metal foil on a bottom surface, the first metal foil being electrically and thermally joined to the first heat spreader and the second heat spreader, and a cooler thermally connected to the second metal foil of the DCB substrate. The first semiconductor element is disposed on an upstream side, and the second semiconductor element is disposed on a downstream side with respect to a flowing direction of a refrigerant of the cooler. An area of the second heat spreader is greater than an area of the first heat spreader.
1. A semiconductor module, comprising:
a first semiconductor element;
a second semiconductor element;
a first heat spreader electrically and thermally connected to a bottom surface of the first semiconductor element;
a second heat spreader electrically and thermally connected to a bottom surface of the second semiconductor element;
a DCB substrate including a ceramic insulating substrate, a first metal foil disposed on a top surface of the ceramic insulating substrate to electrically and thermally join to a bottom surface of the first heat spreader and a bottom surface of the second heat spreader, and a second metal foil disposed on a bottom surface of the ceramic insulating substrate; and
a cooler thermally connected to the second metal foil of the DCB substrate,
wherein the first semiconductor element is disposed on an upstream side and the second semiconductor element is disposed on a downstream side with respect to a flowing direction of a refrigerant of the cooler, and
an area of the second heat spreader is greater than an area of the first heat spreader.
2. The semiconductor module according to claim 1 , wherein a length of the second heat spreader in a direction perpendicular to the flowing direction of the refrigerant is greater than a length of the first heat spreader in the direction perpendicular to the flowing direction of the refrigerant.
3. The semiconductor module according to claim 1 , wherein a length of the second heat spreader in the flowing direction of the refrigerant is greater than a length of the first heat spreader in the flowing direction of the refrigerant.
4. The semiconductor module according to claim 1 , wherein the first metal foil includes a third metal foil disposed on the bottom surface of the first heat spreader and a fourth metal foil disposed on the bottom surface of the second heat spreader.
5. The semiconductor module according to claim 1 , wherein at least one of the first semiconductor element and the second semiconductor element includes a plurality of semiconductor elements disposed to be electrically connected in parallel.
6. The semiconductor module according to claim 5 , wherein at least one of the first heat spreader and the second heat spreader is formed from a plurality of heat spreaders corresponding to the semiconductor elements for the plurality of semiconductor elements disposed to be electrically connected in parallel.
7. The semiconductor module according to claim 5 , wherein the first metal foil includes an extending portion protruding in a direction from downstream to upstream of the refrigerant flow in a region between the plurality of semiconductor elements electrically connected in parallel.
8. The semiconductor module according to claim 1 , further comprising an electrode pad disposed on the ceramic insulating substrate between the first semiconductor element and the second semiconductor element.
9. The semiconductor module according to claim 1 , wherein the first heat spreader has an external form in which a distance from an edge of the first heat spreader to an edge of the first semiconductor element is in a range between 2 mm or more and 10 mm or less, and
the second heat spreader has an external form in which a distance from an edge of the second heat spreader to an edge of the second semiconductor element is within a range between 2 mm or more and 10 mm or less.
10. The semiconductor module according to claim 1 , wherein each of a distance from the top surface of the ceramic insulating substrate to a top surface of the first heat spreader and a distance from the top surface of the ceramic insulating substrate to a top surface of the second heat spreader is between 0.8 mm or more and 2.5 mm or less,
the first heat spreader has an external form in which a distance from an edge of the first heat spreader to an edge of the first semiconductor element is between 2 mm or more and 5 mm or less, and
the second heat spreader has an external form in which a distance from an edge of the second heat spreader to an edge of the second semiconductor element is between 2 mm or more and 5 mm or less.
11. The semiconductor module according to claim 1 , wherein each of a distance from the top surface of the ceramic insulating substrate to a top surface of the first heat spreader and a distance from the top surface of the ceramic insulating substrate to a top surface of the second heat spreader is between 1.5 mm or more and 2.0 mm or less,
the first heat spreader has an external form in which a distance from an edge of the first heat spreader to an edge of the first semiconductor element is between 2 mm or more and 5 mm or less, and
the second heat spreader has an external form in which a distance from an edge of the second heat spreader to an edge of the second semiconductor element is between 2 mm or more and 5 mm or less.
12. The semiconductor module according to claim 5 , wherein a distance between one edge of one of the plurality of first semiconductor elements and one edge of another of the plurality of first semiconductor elements facing the one edge of the one of the plurality of first semiconductor elements is between 1 mm or more and 13 mm or less, or
a distance between one edge of one of the plurality of second semiconductor elements and one edge of another of the plurality of second semiconductor elements facing the one edge of the one of the plurality of second semiconductor elements is between 1 mm or more and 13 mm or less.
13. The semiconductor module according to claim 1 , wherein at least one of the first semiconductor element and second semiconductor element includes a first sensor for measuring either a current or voltage and a second sensor for measuring a temperature.
14. The semiconductor module according to claim 1 , wherein the area of the second heat spreader is increased in a range between 1.2 times or more of the area of the first heat spreader and 2.4 times or less of the area of the first heat spreader.
15. The semiconductor module according to claim 14 , wherein the area of the second heat spreader is increased in a range between 1.5 times or more of the area of the first heat spreader and 2.1 times or less of the area of the first heat spreader.
16. The semiconductor module according to claim 15 , wherein the area of the second heat spreader is increased in a range between 1.8 times or more of the area of the first heat spreader and 2.0 times or less of the area of the first heat spreader.
17. An electrically-driven vehicle, comprising:
a semiconductor module according to claim 1 ;
a motor driven by power output from the semiconductor module;
a central processing unit controlling the semiconductor module;
a pump for transporting a refrigerant for cooling the semiconductor module;
a heat exchanger for cooling the refrigerant; and
a piping connecting the semiconductor module, the pump, and the heat exchanger in closed circuit form to form a refrigerant path.