US Patent 9583487 Semiconductor device having metallic source and drain regions

Semiconductor devices having metallic source and drain regions are described. For example, a semiconductor device includes a gate electrode stack disposed above a semiconducting channel region of a substrate. Metallic source and drain regions are disposed above the substrate, on either side of the semiconducting channel region. Each of the metallic source and drain regions has a profile. A first semiconducting out-diffusion region is disposed in the substrate, between the semiconducting channel region and the metallic source region, and conformal with the profile of the metallic source region. A second semiconducting out-diffusion region is disposed in the substrate, between the semiconducting channel region and the metallic drain region, and conformal with the profile of the metallic drain region.