US Patent 9711414 Strained stacked nanosheet FETS and/or quantum well stacked nanosheet

Exemplary embodiments provide for fabricating a biaxially strained nanosheet. Aspects of the exemplary embodiments include: growing an epitaxial crystalline initial superlattice having one or more periods, each of the periods comprising at least three layers, an active material layer, a first sacrificial material layer and a second sacrificial material layer, the first and second sacrificial material layers having different material properties; in each of the one or more periods, placing each of the active material layers between the first and second sacrificial material layers, wherein lattice constants of the first and second sacrificial material layers are different than the active material layer and impose biaxial stress in the active material layer; selectively etching away all of the first sacrificial material layers thereby exposing one surface of the active material for additional processing, while the biaxial strain in the active material layers is maintained by the second sacrificial material layers; and selectively etching away all of the second sacrificial material layers thereby exposing a second surface of the active material layers for additional processing.