US Patent 11538927 Nanostructures and method for manufacturing the same

Semiconductor structures and the manufacturing method thereof are disclosed. An exemplary manufacturing method includes forming a stack of a first type and a second type epitaxial layers on a frontside of a semiconductor substrate, patterning the stack to form a fin-shaped structure, depositing a dielectric layer on sidewalls of the fin-shaped structure, and recessing the dielectric layer to expose a top portion of the fin-shaped structure. A top surface of the recessed dielectric layer is above a bottom surface of the stack. The exemplary manufacturing method also includes forming a gate structure over the top portion of the fin-shaped structure, etching the semiconductor substrate from a backside of the semiconductor substrate, and etching at least a bottommost first type epitaxial layer and a bottommost second type epitaxial layer through the trench.