A Novel CMP-Less Integration Scheme For Dual Work Function Ni-FUSI CMOS

The authors demonstrate a novel CMP-less FUSI integration scheme which uses a spin-on sacrificial material for planarization showing 45nm gate length Ni-rich FUSI pMOS and NiSi FUSI nMOS transistors on HfSiON. This new scheme does not require CMP but remains compatible with phase-controlled dual-WF CMOS with independent silicidation of the S/D and the gate. This approach uses very selective dry etch processes that result in uniform poly-Si height, widening the RTP process window of NiSi FUSI from 5degC (Kittl et al., 2005) for the CMP approach to 15degC, without additional process complexity. Furthermore it is less disruptive compared to the standard CMP approach making it more compatible with stressed liners