We investigated Si:C S/D stressors having a retrograde carbon profile formed by carbon ion implantation and solid phase epitaxy (SPE). The retrograde carbon profile features a 30-nm-thick buried silicon carbon (Si:C) layer that is spatially decoupled from a 10-nm-thick surface layer with high phosphorus concentration. Retrograde carbon profile can increase the dopant activation rate in the Si:C S/D stressors and achieves more than 30% reduction of sheet resistance (R-s) when SPE temperature is lower than 800 degrees C. Samples with retrograde carbon profile have a lower R-s for a given substitutional carbon concentration compared to the uniform carbon profile samples. Nickel monosilicide (NiSi) formed on Si:C S/D with a retrograde carbon profile has a R-s which similar to 10% lower than that formed on Si:C with uniform C profile. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.072204jes] All rights reserved.