| 摘要 |
PURPOSE:To reduce the fluctuation in power supply potential on power supply line for stabilizing the potential by providing a MOS capacitor using two layer aluminum interconnections on an unused cell. CONSTITUTION:A MOS capacitor is formed between the first layer metallic interconnection layer 15 and the second layer metallic interconnection layer 18 holding an interlayer insulating film 17 on overall surface of an unused transistor of basic cell while the MOS capacitor is connected between VDD and VSS power supplies. Besides. the first layer metallic interconnection layer 15 is brought into ohmic contact with source.drain 13, 14 through the intermediary of contact holes 16 while the potential of source.drain of not yet used P channel type MOS transistor is fixed to VDD power supply. In such a constitution, a gate electrode 12 is connected to the isolated first layer metallic layer 15 through the intermediary of the contact hole 10 so that the potential of the electrode 12 may be fixed to the VSS power supply. Consequently, the structure of this transistor device is extremely resistant to latch up. |
