| abstract |
The present invention relates to nanosheet transistors with improved internal spacers, wherein a method of forming nanosheet and nanowire transistors includes the formation of alternating epitaxial layers of silicon germanium (SiGe) and silicon (Si), wherein each of the silicon The germanium content within the germanium layers varies globally to tune the selective etching of these layers. The germanium content can be controlled such that the recessed regions created by partial removal of the silicon germanium layer have uniform lateral dimensions, and backfilling of the recessed regions with an etch-selective material results in the formation of a robust etch barrier. |