Random electric fields and impurity diffusion in delta layers

Impurity diffusion in the delta layer during the process of its growth has been considered. Experiments show that the spreading of the impurity profil e has a complex dependence on the in-plane impurity concentration. We carri ed out the numerical simulation of the self-consistent diffusion problem fo r the impurities moving in their own random electric field and have shown t hat at some critical impurity concentration in delta layer the impurity dis tribution function perpendicular to the layer acquires a non-Gaussian chara cter.