Pair diffusion models have gained popularity in describing transient enhanced diffusion effects during low thermal budget processes [Mor86], [Mul87], [Cra88], [Mor89], [Orl90]. Our model is based on works of Budil et al. [Bud88] and Heinrich et al. [Hei90].
Dopants 
(at substitutional sites), point defects 
(interstitials 
and vacancies 
) and dopant point-defect pairs (
, 
) are treated
separately. Therefore, three species for each dopant and two additional
species for point defects are required.