Weak localisation and interaction of electrons in MBE delta<Sb>-layers in Si

Temperature (1.6 - 20 K) and magnetic field (up to 2.5 T) dependences of quantum corrections to the conductivity and Hall coefficient of Si epitaxial films containing a delta -layer of different sheet density N-Sb are studied. The quantum corrections are due to the effects of electron weak localization (WL) and electron-electron interaction (EEI). Analysis of the quantum corrections made it possible to determine the temperature dependence of electron phase relaxation time tau(phi), the spin-orbit interaction time tau(so) and the screening factor F. It is found that the dependence tau(phi)(T) is determined by the electron-electron scattering processes, tau(phi) proportional to T--p with p approximate to 1, and an increase in the parameter F with decreasing electron concentration n in the delta-layer is related to the specific features of the screening processes in two-dimensional electron systems