METHOD TO FORM SELF-ALIGNED ELEVATED SOURCE / DRAIN BY SELECTIVE REMOVAL OF GATE DIELECTRIC IN THE SOURCE / DRAIN REGION FOLLOWED BY POLY DEPOSITION AND CMP

摘要

A method of manufacturing a self aligned elevatedsource / drain (S/D). A first insulating layer is formed over asubstrate. The first insulating layer having at least a gateopening and source / drain (S/D) openings adjacent to the gateopening. Spacer portions of the first insulating layer definethe gate opening. A gate dielectric layer is formed over thesubstrate in the gate opening. A conductive layer is formedover the substrate. The conductive layer fills the gate openingand the source / drain (S/D) openings. The conductive layer isdoped with dopants. The conductive layer is planarized to form agate over the gate dielectric layer and filling the gate openingand filling the source / drain (S/D) opening to form elevatedsource / drain (S/D) regions. The conductive layer is preferablyplanarized so that the top surface of the conductive layer islevel with the top surface of the first insulating layer. Thespacer portions are removed to form spacer openings. LDD regionsare formed in the substrate in the spacer opening. A dielectriclayer is formed over the substrate filling the spacer openings.Source / drain (S/D) regions are formed in the substrate underthe elevated source / drain (S/D) regions.