Patent ID: 11791401

Abstract:
A method of fabricating a device includes providing a fin having a plurality of channel layers and a plurality of multilayer epitaxial layers interposing the plurality of channel layers. The multilayer epitaxial layers include a first epitaxial layer interposed between second and third epitaxial layers. The first epitaxial layer has a first etch rate and the second and third epitaxial layers have a second etch rate greater than the first etch rate. The method further includes laterally etching the first, second, and third epitaxial layers to provide a convex sidewall profile on opposing lateral surfaces of the multilayer epitaxial layers. The method further includes forming an inner spacer between adjacent channel layers. The inner spacer interfaces the convex sidewall profile of the multilayer epitaxial layers along a first inner spacer sidewall surface. The method further includes replacing the multilayer epitaxial layers with a portion of a gate structure.