US Patent 7737472 Semiconductor integrated circuit device

A semiconductor integrated circuit device capable of suppressing variations in transistor characteristics due to the well proximity effect is provided. Standard cell rows are arranged in a vertical direction, each standard cell row including standard cells arranged in a horizontal direction. In the standard cell rows, positions of the N well and the P region in the vertical direction are switched every other row. Adjacent standard cell rows share the P region or the N well. A distance from a PMOS transistor located at an end of a standard cell row to an end of an N well is greater than or equal to a width of an N well shared by standard cell rows.