Integrated circuit structures with source or drain dopant diffusion blocking layers

Abstract

Embodiments of the disclosure include integrated circuit structures having source or drain dopant diffusion blocking layers. In an example, an integrated circuit structure includes a fin including silicon. A gate structure is over a channel region of the fin, the gate structure having a first side opposite a second side. A first source or drain structure is at the first side of the gate structure. A second source or drain structure is at the second side of the gate structure. The first and second source or drain structures include a first semiconductor layer and a second semiconductor layer. The first semiconductor layer is in contact with the channel region of the fin, and the second semiconductor layer is on the first semiconductor layer. The first semiconductor layer has a greater concentration of germanium than the second semiconductor layer, and the second semiconductor layer includes boron dopant impurity atoms.