Influence of Si surface on damage generation and recombination

We have studied the influence of Si surface on damage generation and recombination using classical molecular dynamics simulations. We have found that, when approaching to the surface, damage generation is enhanced due to weaker atomic bonding. Furthermore, generated damage is more stable as it reveals the mean lifetime of defects and the activation energy for recombination. Therefore near the surface damage is generated easily and it is more stable than in the bulk. These findings explain the experimental observations of a reduced amorphization threshold for the formation of ultra-shallow junctions and the difficulty to regrowth ultra thin body Si devices.