US Patent 10985279 Source and drain epitaxy and isolation for gate structures

Semiconductor devices and methods for forming the semiconductor devices include forming a sacrificial layer on a substrate on each side of a stack of nanosheets, the stack of nanosheets including first nanosheets and second nanosheets stacked in alternating fashion with a dummy gate structure formed thereon. Source and drain regions are grown on from the sacrificial layer and from ends of the second nanosheets to form source and drain regions in contact with each side of the stack of nanosheets. The sacrificial layer is removed. An interlevel dielectric is deposited around the source and drain regions to fill between the source and drain regions and the substrate.