Semiconductor device having a fin field effect transistor

1. A semiconductor device comprising

a fin field effect transistor configured to include at least a first fin and a second fin, the first fin having a first drain region, the second fin having a second drain region connected to the first drain region; and

a gate electrode provided in common for the first fin and the second fin, wherein

threshold voltage of the first fin and threshold voltage of the second fin are different from each other in the fin field effect transistor.

2. The semiconductor device according to claim 1 , wherein

the first fin and the second fin each extend along a first direction of a substrate plane and are different from each other in width defined in a second direction perpendicular to the first direction.

3. The semiconductor device according to claim 1 , wherein

the first fin and the second fin are different from each other in a doping amount of an impurity element in a channel forming region.

4. The semiconductor device according to claim 1 , wherein

gate length of the first fin and gate length of the second fin are different from each other.

5. The semiconductor device according to claim 1 , wherein

the second fin is provided in plurality, and the first fin and the second fins each extend along a first direction of a substrate plane and are arranged at intervals along a second direction perpendicular to the first direction, and

the first fin and the second fins are arranged symmetrically in the second direction.

6. The semiconductor device according to claim 2 , wherein

the first fin and the second fin are different from each other in a doping amount of an impurity element in a channel forming region.

7. The semiconductor device according to claim 2 , wherein

gate length of the first fin and gate length of the second fin are different from each other.

8. The semiconductor device according to claim 2 , wherein

the second fin is provided in plurality, and the first fin and the second fins each extend along a first direction of a substrate plane and are arranged at intervals along a second direction perpendicular to the first direction, and

the first fin and the second fins are arranged symmetrically in the second direction.

9. The semiconductor device according to claim 1 , wherein the a fin field effect transistor further includes a third fin, wherein the second fin comprises a pair of second fins on either side of the first fin, the third fin comprises a pair of third fins on either side of the second fins.

10. The semiconductor device according to claim 9 , wherein the third fin is wider that the second fin, the second fin being wider than the first fin.

11. The semiconductor device according to claim 10 , wherein a threshold voltage for the third fin is greater than the threshold voltage for the second fin, the threshold voltage for the second fin being greater than the threshold voltage for the first fin.

12. The semiconductor device according to claim 11 , wherein the first fin, the second fin, and the third fins include a source region and drain region formed along a y direction of the semiconductor device, the source region and the drain region sandwich a channel forming region on either side.

13. The semiconductor device according to claim 12 , wherein a silicide layer is formed to cover top surfaces of the source region and the drain region of the first fin.

14. A semiconductor device comprising:

a fin field effect transistor configured to include at least a first fin, a second pair of fins on either side of the first fin, and a third pair of fins on either side of the second pair of fins, a width of the third pair of fins being greater than a width of the second pair of fins, and the width of the second pair of fins being greater than a width of the first fin; and

a gate electrode provided in common for the first fin, the second pair of fins, and the third pair of fins, wherein

a first threshold voltage of the first fin, a second threshold voltage of the second pair of fins, and a third threshold voltage of the third pair of fins are different from each other in the fin field effect transistor.

15. The semiconductor device according to claim 14 , wherein the first fin, the second pair of fins, and the third pair of fins include a source region and drain region formed along a y direction of the semiconductor device, the source region and drain region sandwich a channel forming region on either side.

16. The semiconductor device according to claim 15 , wherein a silicide layer is formed to cover top surfaces of the source regions and the drain regions.

17. The semiconductor device according to claim 14 , wherein a buried oxide film is formed on a substrate of the fin field effect transistor, the gate electrode intersects with the first fin, the second pair of fins, and the third pair of fins at right angles.

18. The semiconductor device according to claim 14 , wherein the first fin, the second pair of fins, and the third pair of fins are separated by intervals, the width of the third pair of fins is wider than the second pair of fins by at least 70 nm, and wherein the width of the second pair of fins is wider than the first fin by at least 70 nm.

19. The semiconductor device according to claim 14 , wherein a length of the first fin, the second pair of fins, and the third pair of fins is identical.