CONSTRAINED EPITAXIAL FORMATION USING DIELECTRIC WALLS

Techniques to form semiconductor devices having one or more epitaxial source or drain regions formed between dielectric walls that separate each adjacent pair of source or drain regions. In an example, a semiconductor device includes a semiconductor region extending in a first direction from a source or drain region. Dielectric walls extend in the first direction adjacent to opposite sides of the source or drain region. The first and second dielectric walls also extend in the first direction through a gate structure present over the semiconductor region. A dielectric liner exists between at least a portion of the first side of the source or drain region and the first dielectric wall and/or at least a portion of the second side of the source or drain region and the second dielectric wall. The dielectric walls may separate the source or drain region from other adjacent source or drain regions.