Semiconductor device having high-K gate insulation films including lanthanum

1. A semiconductor device comprising:

a first gate insulation film on a substrate, the first gate insulation film including a first material selected from the group consisting of HfO 2 , ZrO 2 , Ta 2 O 5 , TiO 2 , SrTiO 3 and (Ba,Sr)TiO 3 ;

a first barrier film on the first gate insulation film, the first barrier film including a second material selected from the group consisting of HfON, HfSiON, ZrON and ZrSiON;

a first gate electrode on the first barrier film;

n-type source/drain regions in the substrate at both sides of the first gate electrode;

a second gate insulation film on the substrate, the second gate insulation film including a third material selected from the group consisting of HfO 2 , ZrO 2 , Ta 2 O 5 , TiO 2 , SrTiO 3 and (Ba,Sr)TiO 3 ;

a second barrier film on the second gate insulation film, the second barrier film including a fourth material selected from the group consisting of HfON, HfSiON, ZrON and ZrSiON;

a second gate electrode on the second barrier film; and

p-type source/drain regions in the substrate at both sides of the second gate electrode,

wherein lanthanum (La) is included in the first gate insulation film and the first barrier film is free of La.

2. The semiconductor device of claim 1 , wherein the first gate insulation film is free of aluminum (Al).

3. The semiconductor device of claim 1 , wherein Al is included in the second gate insulation film.

4. The semiconductor device of claim 1 , wherein the second barrier film is free of Al.

5. The semiconductor device of claim 1 , further comprising an interface film between the substrate and the first gate insulation film.

6. The semiconductor device of claim 1 , wherein the second barrier film is free of La.

7. The semiconductor device of claim 1 , wherein the first barrier film comprises an insulating material and is disposed between the first gate insulation layer and the first gate electrode.

8. The semiconductor device of claim 7 , wherein the first barrier film is free of Al.

9. A semiconductor device comprising:

a first gate insulation layer on a substrate, the first gate insulation layer comprising a first high-k oxide and lanthanum (La) and being free of aluminum (Al);

a first barrier layer on the first gate insulation layer;

a first gate electrode on the first barrier layer;

n-type source/drain regions in the substrate at both sides of the first gate electrode; and

a second gate insulation layer on the substrate, the second gate insulation layer comprising a second high-k oxide and Al;

a second barrier layer on the second gate insulation layer;

a second gate electrode on the second barrier layer; and

p-type source/drain regions in the substrate at both sides of the second gate electrode.

10. The semiconductor device of claim 9 , wherein the second barrier layer is free of Al.

11. The semiconductor device of claim 9 , wherein the second gate insulation layer is free of La.

12. The semiconductor device of claim 9 , wherein the second barrier layer is free of La.

13. The semiconductor device of claim 9 , wherein the first high-k oxide and the second high-k oxide are identical.

14. The semiconductor device of claim 13 , wherein the first high-k oxide and the second high-k oxide comprise a material selected from the group consisting of HfO2, ZrO2, Ta2O5, TiO2, SrTiO3 and (Ba,Sr)TiO3.

15. The semiconductor device of claim 9 , wherein the first barrier layer comprises an insulating material and is disposed between the first gate insulation layer and the first gate electrode.

16. The semiconductor device of claim 15 , wherein the first barrier layer is free of La.

17. The semiconductor device of claim 15 , wherein the first barrier layer is free of Al.