Method and system for designing semiconductor integrated circuit providing dummy pattern in divided layout region

1. A method of designing a semiconductor integrated circuit, said method comprising:

dividing a layout area in which a wiring pattern is disposed, into a plurality of division areas, as executed by a processing unit on a computer;

determining a dummy pattern disposition area provided in each of the plurality of division areas, the dummy pattern disposition area being arranged away from at least one of boundaries between a corresponding division area of the plurality of division areas and adjacent division areas;

adding a dummy pattern to the dummy pattern disposition area of each of the plurality of division areas; and

combining division areas to which the dummy pattern is added

wherein said dummy pattern disposition area is defined inside respective ones of said division areas, and

wherein said dummy pattern disposition area is larger than an area of said dummy pattern.

2. The method according to claim 1 , wherein:

the wiring pattern and the dummy pattern are disposed along a first direction, the boundaries include a first boundary intersecting the first direction, and

each said dummy pattern disposition area is located away from the first boundary by a predetermined distance.

3. The method according to claim 2 , wherein:

the predetermined distance is a smallest wiring interval defined by a design rule.

4. The method according to claim 2 , wherein:

the boundaries include a second boundary parallel with the first direction, and

the dummy pattern disposition area is located on the second boundary.

5. The method according to claim 4 , wherein:

the dummy pattern is disposed on a plurality of wiring tracks running along the first direction, the determining includes:

if the second boundary overlaps any of the wiring tracks, parallel-moving the second boundary to a position at which the second boundary does not overlap any of the wiring tracks; and

determining the dummy pattern disposition area.

6. The method according to claim 1 , wherein:

the dummy pattern is coupled to one of a power supply line and a ground line.

7. The method according to claim 1 , wherein in the adding, the dummy pattern is disposed so that pattern densities of the division areas each satisfy a predetermined criterion.

8. The method according to claim 7 , further comprising:

after the combining, checking whether pattern densities around the boundaries each satisfy the predetermined criterion.

9. The method according to claim 8 , further comprising:

if a pattern density around a boundary of the boundaries does not satisfy the predetermined criterion in the checking, extracting a boundary peripheral area including the boundary from the layout area; and

re-disposing a dummy pattern in the boundary peripheral area so that a pattern density of the boundary peripheral area satisfies the predetermined criterion.

10. The method according to claim 1 , wherein the adding is simultaneously performed with respect to the plurality of division areas.

11. A system for designing a semiconductor integrated circuit, said system comprising:

a storage which stores a layout data representing a wiring pattern;

a first calculator which determines a dummy pattern disposition area provided in each of a plurality of division areas, the dummy pattern disposition area being located away from at least one of boundaries between a corresponding division area of the division areas and adjacent division areas,

the first calculator providing a plurality of division area data with respect to the plurality of division areas, the plurality of division area data each representing a layout of a corresponding division area and a corresponding dummy pattern disposition area, and the first calculator reading the layout data from the storage and divides a layout area in which the wiring pattern is disposed, into a plurality of division areas; and

a plurality of second calculators which receives the plurality of division area data and simultaneously performs adding a plurality of dummy patterns to the dummy pattern disposition areas,

wherein the first calculator receives the plurality of division area data to which the dummy patterns have been added, and combines the plurality of division areas,

wherein said dummy pattern disposition area is defined inside respective ones of said division areas, and

wherein said dummy pattern disposition area is larger than an area of one of said dummy patterns.

12. The method according to claim 1 , wherein the dummy pattern is disposed on a plurality of wiring tracks running along a predetermined direction, the wiring pattern and the dummy pattern being disposed along the predetermined direction.

13. The method according to claim 1 , wherein in the determining the dummy pattern disposition area, if a boundary overlaps one of wiring tracks running along a predetermined direction, the boundary is parallel-moved to a position at which the boundary does not overlap the one of the wiring tracks.

14. The method according to claim 1 , wherein the wiring pattern and the dummy pattern are disposed on wiring tracks running along a predetermined direction.

15. The method according to claim 1 , wherein the wiring pattern is divided by said boundaries.

16. The system according to claim 11 , wherein the dummy patterns are disposed on a plurality of wiring tracks running along a predetermined direction, the wiring pattern and the dummy patterns being disposed along the predetermined direction.

17. The system according to claim 11 , wherein in the determining the dummy pattern disposition area in the first calculator, if a boundary overlaps one of wiring tracks running along a predetermined direction, the boundary is parallel-moved to a position at which the boundary does not overlap the one of wiring tracks.

18. The system according to claim 11 , wherein the wiring pattern and the dummy patterns are disposed on wiring tracks running along a predetermined direction.