Integrated circuit with mixed row heights

1. An integrated circuit structure, comprising:

a plurality of first cell rows extending in a first direction, each of which has a first row height and comprises a plurality of cells disposed therein, wherein for each first cell row of the plurality of first cell rows:

each cell in the first cell row has a cell height equal to the first row height, and

the first cell row comprises a first plurality of active regions each of which continuously extends across the first cell row in the first direction; and

a plurality of second cell rows extending in the first direction, each of which has a second row height different from the first row height and comprises a plurality of cells disposed therein, wherein for each second cell row of the plurality of second cell rows:

each cell in the second cell row has a cell height equal to the second row height, and

the second cell row comprises a second plurality of active regions each of which continuously extends across the second cell row in the first direction.

2. The integrated circuit structure of claim 1 , wherein a first quantity of the first plurality of active regions is associated with the first row height, and a second quantity of the second plurality of active regions is associated with the second row height.

3. The integrated circuit structure of claim 2 , wherein the first quantity is different from the second quantity.

4. The integrated circuit structure of claim 1 , wherein each active region of the first and second pluralities of active regions comprises a region with a fin-shaped structure.

5. The integrated circuit structure of claim 1 , wherein the pluralities of first and second cell rows are arranged in an alternating configuration along a second direction perpendicular to the first direction, such that every two adjacent cell rows along the second direction comprise a first cell row and a second cell row.

6. The integrated circuit structure of claim 1 , wherein the pluralities of first and second cell rows are mixed, along a second direction perpendicular to the first direction, according to a ratio between a number of the plurality of first cell rows and a number of the plurality of second cell rows.

7. The integrated circuit structure of claim 6 , wherein the ratio is one of the following: 1/2, 1/3, 1/4, 2/3, 3/2, 2/1, 3/1, 4/1, and 1/1.

8. An integrated circuit structure, comprising:

a plurality of first cells each having a first cell height, wherein a first subset of the plurality of first cells are disposed along a first direction to form a first cell row; and

a plurality of second cells each having a second cell height different from the first cell height, wherein a second subset of the plurality of second cells are disposed along the first direction to form a second cell row different from the first cell row,

wherein the plurality of first cells each comprises a first plurality of active regions that each continuously extends across the first subset of the plurality of first cells, and wherein the plurality of second cells each comprises a second plurality of active regions that each continuously extends across the second subset of the plurality of second cells.

9. The integrated circuit structure of claim 8 , wherein a first quantity of the first plurality of active regions is associated with the first cell height, and a second quantity of the second plurality of active regions is associated with the second cell height.

10. The integrated circuit structure of claim 8 , wherein a first quantity of the first plurality of active regions is different from a second quantity of the second plurality of active regions.

11. The integrated circuit structure of claim 8 , wherein the first and second pluralities of active regions each comprises a region with a fin-shaped structure.

12. The integrated circuit structure of claim 8 , wherein a third subset of the plurality of first cells are disposed along the first direction in a third cell row different from the first and second cell rows, and a fourth subset of the plurality of second cells are disposed along the first direction in a fourth cell row different from the first and second cell rows.

13. The integrated circuit structure of claim 12 , wherein the first, second, third, and fourth cell rows are arranged in an alternating configuration along a second direction perpendicular to the first direction.

14. An integrated circuit designing system, comprising:

a non-transitory storage medium encoded with a set of instructions; and

a hardware processor communicatively coupled with the non-transitory storage medium and configured to execute the set of instructions, the set of instructions being configured to cause the processor to:

provide a first library comprising a plurality of first cells that each comprises a first plurality of active regions continuously extending along a first direction;

provide a second library comprising a plurality of second cells that each comprises a second plurality of active regions continuously extending along the first direction, wherein respective numbers of the first and second pluralities of active regions are different from each other;

retrieve a first subset of the plurality of first cells from the first library and/or a second subset of the plurality of second cells from the second library; and

place the first subset of the plurality of first cells extending along the first direction to form a first plurality of cell rows and/or the second subset of the plurality of second cells extending along the first direction to form a second plurality of cell rows.

15. The integrated circuit designing system of claim 14 , wherein a first quantity of the first plurality of active regions is associated with a first cell height of the plurality of first cells, and a second quantity of the second plurality of active regions is associated with a second cell height of the plurality of second cells.

16. The integrated circuit designing system of claim 14 , wherein the first and second pluralities of active regions each comprises a region with a fin-shaped structure.

17. The integrated circuit designing system of claim 14 , wherein:

in each of the first plurality of cell rows, the respective first pluralities of active regions of the first subset of the plurality of first cells continuously extend across the first subset of the plurality of first cells, and

in each of the second plurality of cell rows, the respective second pluralities of active regions of the second subset of the plurality of second cells continuously extend across the second subset of the plurality of second cells.

18. The integrated circuit designing system of claim 14 , wherein the set of instructions are configured to further cause the processor to:

place the first and second pluralities of cell rows along a second direction perpendicular to the first direction to form a layout of an integrated circuit.

19. The integrated circuit designing system of claim 18 , wherein the set of instructions are configured to further cause the processor to:

based on a performance requirement of the integrated circuit, determine an arrangement of the first and second pluralities of cell rows along the second direction.

20. The integrated circuit designing system of claim 19 , wherein the set of instructions are configured to further cause the processor to:

based on the performance requirement of the integrated circuit, determine a ratio of a number of the first plurality of cell rows to a number of the second plurality of cell rows arranged along the second direction.