An IC structure includes first and second cell rows extending in a first direction. The first cell row includes first cells each including one or more first fins having first source/drain regions of a first conductivity type and one or more second fins having second source/drain regions of a second conductivity type opposite the first conductivity type. The second cell row includes second cells each including one or more third fins having third source/drain regions of the first conductivity type and one or more fourth fins having fourth source/drain regions of the second conductivity type. The first cells have a same first number of the one or more first fins, and the second cells have a same second number of the one or more third fins less than the first number of the one or more first fins.