| abstract |
A semiconductor device includes a substrate including a plurality of transistor devices formed thereon, at least an epitaxial structure formed in between the transistor devices, and a tri-layered structure formed on the epitaxial structure. The epitaxial structure includes a first semiconductor material and a second semiconductor material, and a lattice constant of the second semiconductor material is larger than a lattice constant of the first semiconductor material. The tri-layered structure includes an undoped epitaxial layer, a metal-semiconductor compound layer, and a doped epitaxial layer sandwiched in between the undoped epitaxial layer and the metal-semiconductor compound layer. The undoped epitaxial layer and the doped epitaxial layer include at least the second semiconductor material. |