Channel structures with sub-fin dopant diffusion blocking layers

Abstract

Embodiments of the disclosure are in the field of advanced integrated circuit structure fabrication and, in particular, integrated circuit structures having channel structures with sub-fin dopant diffusion blocking layers are described. In an example, an integrated circuit structure includes a fin having a lower fin portion and an upper fin portion. The lower fin portion includes a dopant diffusion blocking layer on a first semiconductor layer doped to a first conductivity type. The upper fin portion includes a portion of a second semiconductor layer, the second semiconductor layer on the dopant diffusion blocking layer. An isolation structure is along sidewalls of the lower fin portion. A gate stack is over a top of and along sidewalls of the upper fin portion, the gate stack having a first side opposite a second side. A first source or drain structure at the first side of the gate stack.