Strain-engineered MOSFETs having rimmed source-drain recesses

摘要

An integrated circuit (IC) includes a plurality of strained metal oxide semiconductor (MOS) devices that include a semiconductor surface having a first doping type, a gate electrode stack over a portion of the semiconductor surface, and source/drain recesses that extend into the semiconductor surface and are framed by semiconductor surface interface regions on opposing sides of the gate stack. A first epitaxial strained alloy layer (rim) is on the semiconductor surface interface regions, and is doped with the first doping type. A second epitaxial strained alloy layer is on the rim and is doped with a second doping type that is opposite to the first doping type that is used to form source/drain regions.