The dopant and thermal interaction on solid phase epitaxy (SPE) formed SiC has been investigated. We have studied the impact on substitutional carbon concentration ([C]sub) from various thermal steps including low temperature anneal, SiGe epitaxy thermal budget, RTP, and laser anneal (LSA). Regarding the integration scheme for implementing embedded SiC (eSiC) S/D on NMOS performance enhancement, both post-LDD and post-S/D schemes were studied. The higher [C]sub in post-LDD scheme was observed and the S/D dopants were found to enhance the carbon precipitation into interstitial with conventional RTP/LSA activation thermal processes. The phosphorous implant is also found to degrade [C]sub in comparison to As implant. The higher [C]sub and proximity to channel of formed eSiC in post-LDD scheme are beneficial to device performance. The fabricated eSiC S/D NMOS shows 31% mobility improvement and 7% current enhancement.