Semiconductor device

1. A semiconductor device comprising:

a first semiconductor element;

a lead including a first island portion on which the semiconductor element is mounted;

a heat dissipation member made of a ceramic material for dissipating heat from the island portion; and

a sealing resin covering the semiconductor element, the island portion and a part of the heat dissipation member,

wherein the heat dissipation member includes an exposed surface and a side surface connected to the exposed surface, the exposed surface being exposed from the sealing resin and the side surface being at least partially covered by the sealing resin, and

the side surface includes a smooth portion and a rough portion positioned farther away from the exposed surface than the smooth portion is the smooth portion being smoother than the rough portion.

2. The semiconductor device according to claim 1 , wherein the side surface is provided along an entire periphery of the heat dissipation member.

3. The semiconductor device according to claim 1 , wherein an entirety of the side surface is covered by the sealing resin.

4. The semiconductor device according to claim 1 , wherein the exposed surface is flush with a surface of the sealing resin.

5. The semiconductor device according to claim 1 , wherein the rough portion is positioned inward of the smooth portion as viewed in plan.

6. The semiconductor device according to claim 1 , wherein the smooth portion is perpendicular to the exposed surface.

7. The semiconductor device according to claim 1 , wherein the rough portion is inclined so as to shift inward as viewed in plan with increasing distance from the exposed surface.

8. The semiconductor device according to claim 1 , wherein the side surface comprises a plurality of linear portions as viewed in plan.

9. The semiconductor device according to claim 8 , wherein the heat dissipation member is rectangular.

10. The semiconductor device according to claim 1 , wherein a boundary between the smooth portion and the rough portion is parallel to the exposed surface.

11. The semiconductor device according to claim 1 , further comprising a second semiconductor element and a bonding layer,

wherein the lead includes a second island portion on which the second semiconductor element is mounted,

the bonding layer bonds the first and the second island portions to the heat dissipation member, and

the bonding layer includes a first and a second individual regions provided for the first and the second island portions, respectively, the first individual region and the second individual region being spaced apart from each other.

12. The semiconductor device according to claim 11 , wherein the first individual region has an outer edge positioned inward of an outer edge of the first island portion as viewed in plan, and the second individual region has an outer edge positioned inward of an outer edge of the second island portion as viewed in plan.

13. The semiconductor device according to claim 11 , wherein the heat dissipation member is in a form of a plate.

14. The semiconductor device according to claim 11 , wherein each of the first and the second semiconductor elements is a power semiconductor element.

15. The semiconductor device according to claim 1 , further comprising a bonding layer and a plurality of semiconductor elements including the first semiconductor element,

wherein the lead comprises a plurality of island portions including the first island portion,

the bonding layer bonds the plurality of island portions to the heat dissipation member, and

the bonding layer includes a plurality of individual regions equal in number to the plurality of island portions.

16. The semiconductor device according to claim 15 , wherein at least two of the plurality of semiconductor elements are mounted on one of the plurality of island portions.

17. The semiconductor device according to claim 15 , wherein the plurality of island portions are aligned along a common direction.

18. The semiconductor device according to claim 15 , wherein the lead includes a plurality of terminal portions that are connected to the plurality of island portions and exposed from the sealing resin.

19. The semiconductor device according to claim 1 , wherein the island portion is formed with a plurality of recesses.

20. The semiconductor device according to claim 19 , wherein the plurality of recesses are arranged to surround the semiconductor element.