Semiconductor integrated circuit device including two types of MOSFETS having source/drain region different in sheet resistance from each other

摘要

In the semiconductor integrated circuit device of the present invention which uses MOSFETs as its components, the gate electrode of the MOSFET is constructed by using a silicide gate, a polycide gate or a metal gate. The source-drain region of the MOSFET for the internal circuit which does not require connection to an external circuit has a silicide structure, and the source-drain region of the MOSFET for the buffer circuit which requires a direct connection to an external device has a region which is not of silicide structure at least in a portion adjacent to the gate electrode. The gate electrode and the source-drain region of the internal circuit have low resistances so that it is possible to realize an increase in the operating speed by using them as a part of the wirings. Further, in the source-drain region of the buffer circuit there is provided a region of high resistance in the vicinity of the gate electrode so that it is possible to enhance the ESD resistance.