A simplified 5-species non-equilibrium kinetic model for P diffusion was presented. The resultant system of evolution equations was of simple reaction-diffusion form, with constant diffusivities. Upon using first-order thermodynamic estimates for the reaction rates, the P profile after 10min of pre-deposition exhibited the expected tail. Only when the bimolecular generation-recombination rate was significantly increased did a kink plateau result. This suggested that recombination might be the predominant factor which produced the known non-linearity.

W.B.Richardson, B.J.Mulvaney: Applied Physics Letters, 1988, 53[20], 1917-9