A Cost-Effective LOP/LSTP Integrated CMOS Platform Utilizing Multi-Thickness SiON Gate Dielectrics with Hafnium for 45-nm Node

Integration technique enabling Poly/Hf/SiON gate stack with four different thickness of SiON layer is demonstrated for the first time. Two advantages of hafnium dielectric introduction, which enable low cost integration, are discussed; (i) suppression of reverse narrow channel effect and (ii) sharing of ion implantation processes among core logic (transistors used in logic circuit) and I/O transistors. In addition, mobility improvement techniques by surface roughness and local stress reduction, which enable transistor performance boost with no cost addition, are discussed. These techniques realize highly cost-effective LOP/LSTP integrated CMOS platform for 45 nm node.