Patent attributes
Embodiments of the invention provide a method for forming NFET, PFET, or NFET and PFET nanowire devices on a substrate. According to one embodiment, the method includes providing a film stack containing a Si layer, a SiGe layer, and a Ge layer positioned between the Si layer and the SiGe layer, and selectively removing the Ge layer by etching that is selective to the Si layer and the SiGe layer, thereby forming an opening between the Si layer and the SiGe layer. According to another embodiment, the method providing a film stack containing alternating Si and Ge layers, and selectively removing the Ge layers by etching that is selective to the Si layers. According to another embodiment, the method includes providing a film stack containing a plurality of alternating SiGe and Ge layers, and selectively removing the plurality of Ge layers by etching that is selective to the SiGe layers.