Abstract: Gate electrodes 5A through 5F are formed to have the same geometry, and protruding parts of the gate electrodes 5A through 5F extend across an isolation region onto impurity diffusion regions. The gate electrode 5B and P-type impurity diffusion regions 7B6 are connected through a shared contact 9A1 to a first-level interconnect M1H, and the gate electrode 5E and N-type impurity diffusion regions 7A6 are connected through a shared contact 9A2 to a first-level interconnect M1I. In this way, contact pad parts of the gate electrodes 5A through 5F can be located apart from active regions of a substrate for MOS transistors. This suppresses the influence of the increased gate length due to hammerhead and gate flaring. As a result, transistors TrA through TrF can have substantially the same finished gate length.

Abstract: In layout design of a semiconductor device including a device forming region formed on a substrate; an isolation region formed on the semiconductor substrate so as to surround the device forming region; a gate electrode formed on the device forming region; and a gate interconnect connected to the gate electrode and formed on both sides of the device forming region on the isolation region, the semiconductor device is designed as follows: The gate interconnect has a first portion with a larger dimension along the gate length direction than the gate electrode on one side of the device forming region and has a second portion with a larger dimension along the gate length direction than the gate electrode on the other side of the device forming region; and a distance between the first portion and the device forming region is equal to a distance between the second portion and the device forming region.

Abstract: Gate electrodes 5A through 5F are formed to have the same geometry, and protruding parts of the gate electrodes 5A through 5F extend across an isolation region onto impurity diffusion regions. The gate electrode 5B and P-type impurity diffusion regions 7B6 are connected through a shared contact 9A1 to a first-level interconnect M1H, and the gate electrode 5E and N-type impurity diffusion regions 7A6 are connected through a shared contact 9A2 to a first-level interconnect M1I. In this way, contact pad parts of the gate electrodes 5A through 5F can be located apart from active regions of a substrate for MOS transistors. This suppresses the influence of the increased gate length due to hammerhead and gate flaring. As a result, transistors TrA through TrF can have substantially the same finished gate length.

Abstract: A first-conductive-type doped layer is provided on a second-conductive-type well, and a gate electrode of a MOS transistor and the first-conductive-type doped layer are connected to each other via a plug for filling a contact hole and a metal interconnect of Cu. Furthermore, a second-conductive-type doped layer is provided on a first-conductive-type well, and a gate electrode of a MOS transistor and the second-conductive-type doped layer are connected to each other via a plug for filling a contact hole and a metal interconnect of Cu. Then, a first diode and a second diode are provided between the gate electrode and the second-conductive-type well and between the gate electrode and the first-conductive-type well, respectively. Thus, antenna damage generated in the gate electrodes of the MOS transistors is prevented.