Effects of "fast" rapid thermal anneals on sub-keV boron and BF2 ion implants

The effects of "fast" ramp-rates (up to 425 degrees C/s) and spike anneals are investigated for 0.25 keV, 0.5 keV, and 1.0 keV(11)B+ and for 1.1 and 2.2 keV BF2 at a dose of 1e15/cm(2). Below an implant energy threshold where no extended defects form, fast ramp-rates become important in minimizing the thermal diffusion component and reducing the junction depth. Above this implant energy threshold, TED minimizes the advantages of these fast ramp-rates. Annealing in a low and controlled O-2 ppm in N-2 ambient further reduces diffusion by minimizing/eliminating oxygen related enhanced diffusion effects, while simultaneously optimizing anneal reproducibility and across-the-water uniformity.