Integrated circuit including a modified cell and a method of designing the same
A method of designing an integrated circuit includes receiving input data defining the integrated circuit, receiving information from a standard cell library including a plurality of standard cells, receiving information from a modified cell library including at least one modified cell having a same function as a corresponding standard cell among the plurality of standard cells and having a higher routability than the corresponding standard cell and generating output data by performing placement and routing in response to the input data, the information from the standard cell library and the information from the modified cell library.
1. A method of designing an integrated circuit, comprising:
receiving input data defining the integrated circuit;
receiving information from a standard cell library including a plurality of standard cells;
receiving information from a modified cell library including at least one modified cell having a same function as a corresponding standard cell among the plurality of standard cells and having a higher routability than the corresponding standard cell; and
generating, by using a processor, output data by performing placement and routing in response to the input data, the information from the standard cell library and the information from the modified cell library, wherein generating the output data includes:
performing the placement and routing using the standard cells; and
when the placement and routing using the standard cells fails, replacing the corresponding standard cell with the at least one modified cell,
wherein a width of a power rail of the at least one modified cell is smaller than a width of a power rail of the corresponding standard cell, and
the width of the power rail of the at least one modified cell is smaller than a width of a power rail of another standard cell arranged adjacent to the at least one modified cell in a row such that the routability of the at least one modified cell is greater than a routability of the another standard cell.
2. The method of claim 1 , wherein a number of pin points of the at least one modified cell is larger than a number of pin points of the corresponding standard cell, wherein the pin points are positions for signal input or signal output.
3. The method of claim 1 , wherein a width of an upper power rail of the at least one modified cell is smaller than a width of an upper power rail of the corresponding standard cell, or a width of a lower power rail of the at least one modified cell is smaller than a width of a lower power rail of the corresponding standard cell.
4. The method of claim 1 , wherein a size of the at least one modified cell is equal to a size of the corresponding standard cell.
5. The method of claim 1 , wherein an upper power rail or a lower power rail of the at least one modified cell is asymmetrically divided along a cell boundary.
6. The method of claim 1 , wherein the at least one modified cell includes a dummy gate line and the corresponding standard cell does not include a dummy gate line.
7. The method of claim 6 , wherein the at least one modified cell further includes:
an internal connection wiring that is electrically connected to the dummy gate line.
8. The method of claim 7 , wherein the internal connection wiring has only one, jogging portion, wherein the jogging portion is a portion of the internal connection wiring that forms a right angle.
9. The method of claim 7 , wherein the internal connection wiring includes a wiring segment that is formed over the dummy gate line in parallel with the dummy gate line and is electrically connected to the dummy gate line, wherein the wiring segment includes a first portion and a second portion that are overlapped with each other and formed using different etching masks.
10. The method of claim 6 , wherein the at least one modified cell further includes:
at least one jumper structure that includes first contacts formed on active regions at both sides of the dummy gate line and a second contact formed on the dummy gate line to electrically connect the active regions to the dummy gate line.
11. The method of claim 10 , wherein the at least one modified cell further includes:
an internal connection wiring including a wiring segment that is formed over the dummy gate line in parallel with the dummy gate line and is electrically connected to the dummy gate line;
a third contact formed on the dummy gate line and spaced apart from the jumper structure; and
a via contact formed on the third contact to electrically connect the third contact to the wiring segment.
12. The method of claim 6 , wherein the dummy gate line includes a first gate segment and a second gate segment that are separated by a gate cut region.
13. The method of claim 12 , wherein the first gate segment is electrically connected to active regions at both sides of the first gate segment through a first jumper structure and the second gate segment is electrically connected to active regions at both sides of the second gate segment through a second jumper structure.