Defect reduction and dopant activation of in situ phosphorus-doped silicon on a (111) silicon substrate using nanosecond laser annealing

In situ phosphorus-doped silicon (ISPD) has been actively investigated as a source/drain material. However, defect formation during the epitaxial growth of ISPD layers in 3D structures deteriorate the device performance. In this study, we investigate the elimination of inherent defects in ISPD layers using nanosecond laser annealing (NLA). High-density twin- and stacking-fault defects in the ISPD layers cause strain relaxation and dopant deactivation. The NLA process dramatically reduces or eliminates the defects, consequently generating the strain and electrically activating the incorporated phosphorous. The ISPD epitaxial growth and subsequent NLA processes will be robust methods for the fabrication of advanced 3D devices. (author)