Sub-amorphizing Si pre-implantation was combined with relatively high doses (1014/cm2) of implanted B. It was found that spreading resistance profiling could be used to optimize the Si implant energy. The resultant dopant profiles showed that not only was channelling suppressed and dopant diffusion reduced, but activation could also be controlled. Equivalent medium-doped regions, 150nm in extent, were created by conventional furnace annealing. It was concluded that sub-amorphizing Si pre-implants could be used to create very shallow junctions in the medium-dose drain regions of devices.

Optimized Sub-Amorphizing Silicon Implants to Modify Diffusion and Activation of Arsenic, Boron and Phosphorus Implants for Shallow Junction Creation S.Aronowitz, H.Puchner, J.Kimball: Journal of Applied Physics, 1999, 85[7], 3494-8