Low-temperature electron transport in Si with an MBE-grown Sb δ layer

Studies of the electrical properties of Si single crystals with δ(Sb) layers of various sheet densities $N_D,$ of Sb atoms $(5\mathrm{}\times {10}^{12}–3\times {10}^{14}{\mathrm{cm}}^{\mathrm{-}2})$ have furnished detailed information about the low-temperature features of the electron transport in this system. The metal-type conductivity of δ layers at $N_D>~3\times {10}^{13}{\mathrm{cm}}^{\mathrm{-}2}$ exhibits manifestations of the weak localization of electrons and electron-electron interaction in a two-dimensional system. The temperature dependence of electron phase relaxation time, the spin-orbit interaction time, and parameter ${\lambda }^D$ of the electron-electron interaction are determined. It is found that a decrease in the electron density in the δ layer is accompanied by decrease in the parameter ${\lambda }^D.$ The effect of electron heating by an electric field is used to find the temperature dependence of the electron-phonon relaxation time. At low temperature the hopping-type conductivity of δ layers at $N_D<~1\times {10}^{13}{\mathrm{cm}}^{\mathrm{-}2}$ is realized; at sufficiently low temperatures (