Gate-workfunction engineering using poly-(Si,Ge) for high-performance 0.18 /spl mu/m CMOS technology

We show that poly-SiGe can be readily integrated as a gate material into an existing CMOS technology to achieve significant increase in the transistor performance. In order to preserve the standard salicidation scheme, a buffer poly-Si layer is introduced in the gate stack. PMOST channel profiles are optimized to account for the change of the gate workfunction. High-performance CMOS 0.18 /spl mu/m devices are manufactured using p- and n-type poly-Si/Si/sub 0.8/Ge/sub 0.2/ gates.