The electronic properties of the (111)Si/SiO2 interface and its characteristic defect, Pb, were studied. The interface was modelled as a SiO2 Bethe lattice which was attached to a semi-infinite Si crystal. The study took account of changes in the defect-state energies and of charge transfer across the interface towards nearest-neighbor O atoms. Green's function techniques were used to consider electron-electron correlations within an extended Hubbard-like Hamiltonian and within an unrestricted spin Hartree-Fock approximation. It was concluded that taking account of the above correlations resulted in a satisfactory agreement between the present results and the available experimental data.

M.R.Beltrán: Physical Review B, 1994, 50[15], 10915-23