The properties of nanostructures such as ultra-thin layers 50nm in thickness or smaller were strongly dependent on the state of a defect sub-system in the layers. The present objective was to study the influence of charge states and internal elastic stress on the transport of point defects in Si. The equation for the diffusion of point defects, taking account of the contributions of different charge states of defects to the transport process, was reduced to a form which was convenient for numerical solution. For this purpose, the effective diffusivity of point defects was obtained as a function of the dopant concentration and empirical parameters. The effective coefficient of the absorption of point defects by immobile sinks was also obtained in a similar convenient form. By using the modified equation for the diffusion of point defects, the transport processes of diffusing species were simulated for various charge states of the defects and for non-uniform dopant distributions. The cases of zero and non-zero elastic stresses were investigated.

The Influence of Charge States and Elastic Stresses on the Diffusion of Point Defects in Silicon. O.I.Velichko, A.K.Fedotov: Materials Science and Engineering B, 2003, 99[1-3], 567-71