HIGH-K LAYER CHAMFERING TO PREVENT OXYGEN INGRESS IN REPLACEMENT METAL GATE (RMG) PROCESS

A semiconductor structure includes a semiconductor substrate having an outer surface; a plurality of oxide regions, located outward of the outer surface, and defining a plurality of metal-gate-stack-receiving cavities; and a liner interspersed between the plurality of oxide regions and the semiconductor substrate and between the plurality of oxide regions and the plurality of metal-gate-stack-receiving cavities. A layer of high-K material is deposited over the semiconductor structure, including on outer surfaces of the plurality of oxide regions, outer edges of the liner, on walls of the plurality of metal-gate-stack-receiving cavities, and on the outer surface of the semiconductor substrate within the plurality of metal-gate-stack-receiving cavities. The layer of high-K material is chamfered to remove same from the outer surfaces of the plurality of oxide regions, the outer edges of the liner, and partially down the walls of the plurality of metal-gate-stack-receiving cavities.