ANOMALOUS DIFFUSION AND SEPARATION OF IMPLANTED IMPURITIES IN THE ELASTIC-STRAIN FIELDS

A model is developed that takes into account the occurrence of an addi tional motive force of diffusion as well as the dependence of that for ce on the dose of an implanted impurity, The force is induced by the l attice distortions and consequent mechanical stresses, Increments of t he ion-penetration depth and the diffusion coefficients of the impurit ies under the ion-implantation conditions were estimated through compu ter simulation. The proposed model predicts sufficiently well the diff usion anomalies, revealed by experiment, The migration velocity of an impurity was found to depend on the density and fluence of the implant ed atoms. In the case that two impurities are being implanted whose at omic diameters are different the impurities separate due to interactio n with one anther.