Semiconductor device including power rail

A semiconductor device comprising:

• a first cell;
• a second cell;
• a first power rail configured to supply power to the first cell, the first power rail being located on a first layer and the first power rail using the first layer with the first cell;
• and
• a second power rail configured to supply power to the first cell, the second power rail being located on a second layer and the second power rail using the second layer with the first cell,
• wherein the first power rail and the second power rail extend in a first direction,
• wherein the first power rail has a first section which is in direct contact with the first cell in the first direction and a second section which, along the first direction, is only in direct contact with the second cell,
• wherein a width of the second section in a second direction is greater than a width of the first section in the second direction, the second direction being perpendicular to the first direction,
• wherein the second power rail has a third section which is connected with the first cell in the first direction and a fourth section which is connected with the second cell in the first direction,
• wherein a width of the third section in the second direction and a width of the fourth section in the second direction are uniform,
• wherein the first layer and the second layer are spaced apart from each other in a third direction perpendicular to the first direction and the second direction, and
• wherein the first power rail and the second power rail are spaced apart from each other in the third direction,
• wherein the first cell is a standard cell, and the second cell is a filler cell or a decoupling capacitor cell,
• wherein the first power rail is expandable only in the second section, and
• wherein the width of the first power rail is uniform except the second section.

A semiconductor device comprising

• a first power rail configured to transfer power to at least one first cell, the first power rail having a line shape extending longitudinally along a first direction, the first power rail being located on a first layer and the first power rail using the first layer with the first cell, and
• a second power rail configured to transfer power to the first cell and a second cell, the second power rail having a line shape extending longitudinally along the first direction, the second power rail being located on a second layer, and the second power rail using the second layer with the first cell,
• wherein the first power rail has a first section which is in direct contact with the first cell in the first direction and a second section which, along the first direction, is only in direct contact with the second cell,
• wherein a width of the second section in a second direction is greater than a width of the first section in the second direction, the first direction being perpendicular to the second direction,
• wherein the second power rail has a third section which is connected with the first cell in the first direction and a fourth section which is connected with the second cell in the first direction,
• wherein the first power rail and the second power rail are spaced apart from each other in a third direction perpendicular to the first direction and the second direction, and wherein the first cell is a standard cell, and the second cell is a filler cell or a decoupling capacitor cell,
• wherein the first power rail is expandable only in the second section, and
• wherein the width of the first power rail is uniform except the second section.