Silicides as the New IGFET Gate Electrode/Interconnect

The evolution from the LSI to the VLSI era has created new technology limitations that are primarily a result of simple device scaling and high density lithographic capability. As linewidths decrease and circuit density/complexity increases, signal propagation delay penalties offset the advantages of physical scaling. Techniques and materials to decrease wiring capacitance and/or wiring resistivity are needed. The direct replacement of the polysilicon gate electrode in an IGFET environment by a refractory metal(l), refractory silicide(2, 3, 4), or a composite of polysilicon and refractory silicide(5, 6, 7) reduces the line resistivity by at least 1OX.