A method of forming an integrated circuit includes placing a first and a second standard cell layout design of the integrated circuit on a layout design, and manufacturing the integrated circuit based on at least the first or second standard cell layout design. The first standard cell layout design has a first height. The second standard cell layout design has a second height. Placing the first standard cell layout design includes placing a first set of pin layout patterns on a first layout level over a first set of gridlines, extending in a first direction, and having a first width in a second direction. Placing the second standard cell layout design includes placing a second set of pin layout patterns on the first layout level over a second set of gridlines, extending in the first direction, and having a second width in the second direction.