Semiconductor structures and methods thereof

Abstract

A structure has stacks of semiconductor layers over a substrate and adjacent a dielectric feature. A gate dielectric is formed wrapping around each layer and the dielectric feature. A first layer of first gate electrode material is deposited over the gate dielectric and the dielectric feature. The first layer on the dielectric feature is recessed to a first height below a top surface of the dielectric feature. A second layer of the first gate electrode material is deposited over the first layer. The first gate electrode material in a first region of the substrate is removed to expose a portion of the gate dielectric in the first region, while the first gate electrode material in a second region of the substrate is preserved. A second gate electrode material is deposited over the exposed portion of the gate dielectric and over a remaining portion of the first gate electrode material.