A semiconductor cell structure includes four transistors, two gate-strips, four pairs of conductive segments, and a plurality of horizontal routing lines. Each of the two gate-strips intersects a first-type active zone and a second-type active zone. A first conductive segment is configured to have a first supply voltage. A second conductive segment is configured to have a second supply voltage. The first gate-strip is conductively connected to the second conductive segment. Each of the horizontal routing lines intersects one or more conductive segments over one or more corresponding intersections while conductively isolated from the one or more conductive segments at each of the one or more corresponding intersections.