Wrap-Around Contact

摘要

Fin structures are formed on a substrate. An isolation region is between the fin structures. The fin structures comprise epitaxial regions extending above the isolation region. Each of the epitaxial regions has a widest mid-region between an upper-surface and an under-surface. A dual-layer etch stop is formed over the fin structures and comprises a first sub-layer and a second sub-layer. The first sub-layer is along the upper- and under-surfaces and the isolation region. The second sub-layer is over the first sub-layer and along the upper-surfaces, and the second sub-layer merges together proximate the widest mid-regions of the epitaxial regions. Portions of the dual-layer etch stop are removed from the upper- and under-surfaces. A dielectric layer is formed on the upper- and under-surfaces. A metal layer is formed on the dielectric layer on the upper-surfaces. A barrier layer is formed on the metal layer and along the under-surfaces.

主权项

1. A method comprising:
forming a first fin structure and a second fin structure on a substrate, an isolation region being disposed between the first fin structure and the second fin structure, the first fin structure comprising a first epitaxial region extending above the isolation region, the second fin structure comprising a second epitaxial region extending above the isolation region, each of the first epitaxial region and the second epitaxial region having a widest mid-region between an upper-surface and an under-surface; forming a dual-layer etch stop over the first fin structure and the second fin structure, the dual-layer etch stop comprising a first sub-layer and a second sub-layer, the first sub-layer being along the upper-surface of the first epitaxial region, the under-surface of the first epitaxial region, the upper-surface of the second epitaxial region, the under-surface of the second epitaxial region, and the isolation region, the second sub-layer being over the first sub-layer and along the upper-surface of the first epitaxial region and the upper-surface of the second epitaxial region, the second sub-layer merging together proximate the widest mid-region of the first epitaxial region and the widest mid-region of the second epitaxial region; removing at least portions of the dual-layer etch stop from the upper-surface and the under-surface of the first epitaxial region and from the upper-surface and the under-surface of the second epitaxial region; forming a first dielectric layer on at least portions of the upper-surface and the under-surface of the first epitaxial region and on the upper-surface and the under-surface of the second epitaxial region; forming a metal layer on the first dielectric layer on at least the upper-surface of the first epitaxial region and the upper-surface of the second epitaxial region; and forming a barrier layer on the metal layer and along the under-surface of the first epitaxial region and the under-surface of the second epitaxial region.