Semiconductor integrated circuits having contacts spaced apart from active regions

1. A semiconductor integrated circuit, comprising:

first and second active regions defined by an isolation layer on a substrate, the first and second active regions being doped with different types of impurities, the first and second active regions extending in a first direction, and the first and second active regions being spaced apart from each other in a second direction, the second direction being substantially perpendicular to the first direction;

a first gate structure, a second gate structure, a third gate structure, and a fourth gate structure, wherein

the first and third gate structures are on the first active region and a first portion of the isolation layer between the first and second active regions, the first and third gate structures extend in the second direction, and the first and third gate structures are spaced apart from each other in the first direction, and

the second and the fourth gate structures are on the second active region and the first portion of the isolation layer, the second and fourth gate structures extend in the second direction, the second and fourth gate structures are spaced apart from each other in the first direction, and the second and fourth gate structures face and are spaced apart from the first and third gate structures, respectively, in the second direction;

a first contact, a second contact, a third contact, and a fourth contact, the first to fourth contacts being on portions of the first to fourth gate structures, respectively, wherein

the first and fourth contacts are electrically connected to each other,

the second and third contacts are electrically connected to each other,

the first and third contacts are spaced apart from the first active region in the second direction by substantially the same distance, and

the second and fourth contacts are spaced apart from the second active region in the second direction by substantially the same distance;

a fifth gate structure on the first active region and the first portion of the isolation layer, the fifth gate structure extending in the second direction, and being spaced apart from the third gate structure in the first direction; and

a sixth gate structure on the second active region and the first portion of the isolation layer, the sixth gate structure extending in the second direction, and being spaced apart from the fourth gate structure in the first direction, wherein

the fifth and sixth gate structures are connected to each other on the first portion of the isolation layer, and

the fifth and sixth gate structures extend in the second direction.

2. The semiconductor integrated circuit of claim 1 , further comprising:

a first impurity region, a second impurity region, a third impurity region, and a fourth impurity region, wherein

the first and third impurity regions are at upper portions of the first active region at opposite sides of the fifth gate structure, respectively, and the first and third impurity regions are doped with impurities of a first conductivity type, and

the second and fourth impurity regions are at upper portions of the second active region at opposite sides of the sixth gate structure, respectively, and the second and fourth impurity regions are doped with impurities of a second conductivity type.

3. The semiconductor integrated circuit of claim 2 , further comprising:

a fifth contact on the third impurity region, the fifth contact being coupled to a supply voltage; and

a sixth contact on the fourth impurity region, the sixth contact being grounded.

4. The semiconductor integrated circuit of claim 2 , further comprising:

a seventh gate structure on the first active region and the first portion of the isolation layer, the seventh gate structure extending in the second direction, and being spaced apart from the fifth gate structure in the first direction; and

an eighth gate structure on the second active region and the first portion of the isolation layer, the eighth gate structure extending in the second direction, and being spaced apart from the sixth gate structure in the first direction, wherein

the seventh and eighth gate structures are connected to each other on the first portion of the isolation layer, and

the seventh and eighth gate structures extend in the second direction.

5. The semiconductor integrated circuit of claim 3 , further comprising:

a first lower wiring on the fifth contact, the first lower wiring being configured to apply the supply voltage to the fifth contact; and

a second lower wiring on the sixth contact, the second lower wiring being grounded.

6. The semiconductor integrated circuit of claim 4 , further comprising:

a fifth impurity region, a sixth impurity region, a seventh impurity region, and an eighth impurity region, wherein

the fifth and seventh impurity regions are at upper portions of the first active region at opposite sides of the first gate structure, respectively, and the fifth and seventh impurity regions are doped with impurities of a first conductivity type, and

the sixth and eighth impurity regions are at upper portions of the second active region at opposite sides of the second gate structure, respectively, and the sixth and eighth impurity regions are doped with impurities of a second conductivity type.

7. The semiconductor integrated circuit of claim 4 , further comprising:

a fifth impurity region at an upper portion of the second active region adjacent to the eighth gate structure, wherein

the fifth impurity region is electrically connected to the fifth gate structure or the sixth gate structure.

8. A semiconductor integrated circuit, comprising:

first and second active regions defined by an isolation layer on a substrate, the first and second active regions being doped with different types of impurities, the first and second active regions extending in a first direction, and the first and second active regions being spaced apart from each other in a second direction, the second direction being substantially perpendicular to the first direction;

a first gate structure, a second gate structure, a third gate structure, and a fourth gate structure, wherein

the first and third gate structures are on the first active region and a portion of the isolation layer adjacent to the first active region, the first and third gate structures extend in the second direction, and the first and third gate structures are spaced apart from each other in the first direction, and

the second and fourth gate structures are on the second active region and a portion of the isolation layer adjacent to the second active region, the second and fourth gate structures extend in the second direction, the second and fourth gate structures are spaced apart from each other in the first direction, and the second and fourth gate structures face and are spaced apart from the first and third gate structures, respectively, in the second direction;

a fifth gate structure on the first active region and the isolation layer, the fifth gate structure extending in the second direction, and being spaced apart from the third gate structure in the first direction;

a sixth gate structure on the second active region and the isolation layer, the sixth gate structure extending in the second direction, and being spaced apart from the fourth gate structure in the first direction, wherein

the fifth and sixth gate structures are connected to each other on a portion of the isolation layer between the first and second active regions,

the fifth and sixth gate structures extend in the second direction,

a seventh gate structure on the first active region and the isolation layer, the seventh gate structure extending in the second direction, and being spaced apart from the fifth gate structure in the first direction;

an eighth gate structure on the second active region and the isolation layer, the eighth gate structure extending in the second direction, and being spaced apart from the sixth gate structure in the first direction, wherein

the seventh and eighth gate structures are connected to each other on the portion of the isolation layer between the first and second active regions, and

the seventh and eighth gate structures extend in the second direction; and

a first contact, a second contact, a third contact, and a fourth contact, wherein

the first to fourth contacts are on portions of the first to fourth gate structures, respectively,

the first and fourth contacts are electrically connected to each other,

the second and third contacts are electrically connected to each other,

the first and third contacts are spaced apart from a boundary of the first active region in the second direction by substantially the same distance, and

the second and fourth contacts are spaced apart from a boundary of the second active region in the second direction by substantially the same distance.

9. The semiconductor integrated circuit of claim 8 , further comprising:

a first impurity region, a second impurity region, a third impurity region, and a fourth impurity region, wherein

the first and third impurity regions are at upper portions of the first active region at opposite sides of the first gate structure, respectively, and the first and third impurity regions are doped with impurities of a first conductivity type,

the second and fourth impurity regions are at upper portions of the second active region at opposite sides of the second gate structure, respectively, and the second and fourth impurity regions are doped with impurities of a second conductivity type,

the first and second impurity regions are electrically connected to each other, and

the third and fourth impurity regions are electrically connected to each other.

10. The semiconductor integrated circuit of claim 8 , wherein

the second and third gate structures are configured to receive a first clock signal; and

the first and fourth gate structures are configured to receive a second clock signal.

11. The semiconductor integrated circuit of claim 9 , wherein the seventh and eighth gate structures are electrically connected to the third and fourth impurity regions, respectively.

12. The semiconductor integrated circuit of claim 9 , further comprising:

a fifth impurity region, a sixth impurity region, a seventh impurity region, and an eighth impurity region, wherein

the fifth and seventh impurity regions are at upper portions of the first active region at opposite sides of the fifth gate structure, respectively, and the fifth and seventh impurity regions are doped with impurities of the first conductivity type,

the sixth and eighth impurity regions are at upper portions of the second active region at opposite sides of the sixth gate structure, respectively, and the sixth and eighth impurity regions are doped with impurities of the second conductivity type,

the seventh impurity region is configured to receive a supply voltage, and

the eighth impurity region is grounded.

13. The semiconductor integrated circuit of claim 12 , further comprising:

a ninth impurity region at an upper portion of the second active region adjacent to the eighth gate structure, the ninth impurity region being doped with impurities of the second conductivity type, wherein

the ninth impurity region is electrically connected to the fifth and sixth gate structures.

14. A method of manufacturing a semiconductor integrated circuit, the method comprising:

forming an isolation layer on a substrate to define first and second active regions, the first and second active regions extending in a first direction and being spaced apart from each other in a second direction, the second direction being substantially perpendicular to the first direction;

forming gate structures on the first active region, the second active region, and portions of the isolation layer, wherein

first and third gate structures are formed on the first active region and a portion of the isolation layer adjacent to the first active region, the first and third gate structures extend in the second direction, and the first and third gate structures are spaced apart from each other in the first direction, and

second and fourth gate structures are formed on the second active region and a portion of the isolation layer adjacent to the second active region, the second and fourth gate structures extend in the second direction, the second and fourth gate structures are spaced apart from each other in the first direction, and the second and fourth gate structures face and are spaced apart from the first and third gate structures, respectively, in the second direction;

forming first, second, third, and fourth contacts on portions of the first, second, third, and fourth gate structures, respectively;

electrically connecting the first and fourth contacts to each other; and

electrically connecting the second and third contacts to each other, wherein

the first and third contacts are spaced apart from the first active region in the second direction by substantially the same distance, and

the second and fourth contacts are spaced apart from the second active region in the second direction by substantially the same distance.

15. The method of claim 14 , further comprising:

doping, with p-type impurities, upper portions of the first active region adjacent to the first and third gate structures; and

doping, with n-type impurities, upper portions of the second active region adjacent to the second and fourth gate structures.

16. The method of claim 14 , wherein the electrically connecting the first and fourth contacts to each other comprises:

forming a first lower wiring on the first and fourth contacts.

17. The method of claim 14 , wherein the electrically connecting the second and third contacts to each other comprises:

forming first and second lower wirings on the second and third contacts, respectively;

forming first and second vias on the first and second lower wirings, respectively; and

forming a first upper wiring on the first and second vias.

18. The method of claim 14 , further comprising:

doping, with impurities of a first conductivity type, upper portions of the first active region at opposite sides of the first gate structure to form first and third impurity regions, respectively; and

doping, with impurities of a second conductivity type, upper portions of the second active region at opposite sides of the second gate structure to form second and fourth impurity regions, respectively.

19. The method of claim 18 , further comprising:

forming fifth and sixth contacts on the first and second impurity regions, respectively;

forming first and second lower wirings on the fifth and sixth contacts, respectively;

forming first and second vias on the first and second lower wirings, respectively; and

forming a first upper wiring on the first and second vias.

20. The method of claim 18 , further comprising:

forming fifth and sixth contacts on the third and fourth impurity regions, respectively;

forming first and second lower wirings on the fifth and sixth contacts, respectively;

forming first and second vias on the first and second lower wirings, respectively; and

forming a first upper wiring on the first and second vias.