Author:

Keywords:

Science & Technology, Physical Sciences, Physics, Applied, Physics, INTERSTITIAL CLUSTERS, BORON, DISSOLUTION, ACTIVATION, MECHANISMS, SILICON, 02 Physical Sciences, 09 Engineering, 10 Technology, Applied Physics, 40 Engineering, 51 Physical sciences

Abstract:

© 2014 AIP Publishing LLC. A series of B implantation experiments into initially amorphized and not fully recrystallized Si, i.e., into an existing a/c-Si bi-layer material, have been conducted. We varied B dose, energy, and temperature during implantation process itself. Significant B migration has been observed within c-Si part near the a/c-interface and near the end-of-range region before any activation annealing. We propose a general concept of local trapping sites as experimental probes of nanoscale reaction-diffusion processes. Here, the a/c-Si interface acts as a trap, and the process itself is explored as the migration and clustering of mobile BI point defects in nearby c-Si during implantation at temperatures from 77 to 573K. We find that at room temperature - even at B concentrations as high as 1.6 atomic %, the key B-B pairing step requires diffusion lengths of several nm owing to a small, ∼0.1 eV, pairing energy barrier. Thus, in nanostructures doped by ion implantation, the implant distribution can be strongly influenced by thermal migration to nearby impurities, defects, and interfaces.