abstract |
A material stack comprising alternating layers of a silicon etch stop material and a germanium nanowire template material is formed on a surface of a bulk substrate. The material stack and a portion of the bulk substrate are then patterned by etching to provide an intermediate fin structure including a base semiconductor portion and alternating portions of the silicon etch stop material and the germanium nanowire template material. After recessing each germanium nanowire template material and optionally the base semiconductor portion, and etching each silicon etch stop material to define a new fin structure, a spacer is formed on sidewall surfaces of the remaining portions of the new fin structure. The alternating layers of germanium nanowire template material are then suspended above a notched surface portion of the bulk substrate and thereafter a functional gate structure is formed. |