R4 has a small improvement in epi height (1-2 nm) and a significant improvement in doping. The doping of this recipe reaches around 1.8E21/cm 3 . But, we have lost crystallinity due to the increased temperature. R5 has shown a significant improvement in doping (~ 2E21/cm 3 ) while maintaining an epi height ~ 21 nm. But the crystallinity has been severely compromised.