In order to simulate the transient enhanced diffusion near the surface or interface, a set of equations describing the impurity diffusion and quasi-chemical reactions of

dopant atoms and point defects in shallow ion-implanted layers was proposed and analyzed. The diffusion equations obtained take into account different charge states of mobile or immobile species and drift the mobile species in the built-in electric field and field of elastic stresses. The absorption of self-interstitials on the surface and drift of the defects due to elastic stresses result in the non-uniform distributions of point defects. It was shown analytically and by means of numerical calculations that consideration of the non-uniform defect distributions enables one to explain the phenomenon of so-called up-hill impurity diffusion near the surface during annealing of ion-implanted layers. The performed calculations of the boron concentration profile after annealing of a shallow implanted layer agreed well with the experimental data confirming the efficiency of the proposed equations.

Set of Equations for Transient Enhanced Diffusion in Shallow Ion-Implanted Layers. O.I.Velichko, Y.P.Shaman, A.K.Fedotov, A.V.Masanik: Computational Materials Science, 2008, 43[2], 279-85