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    Ionized impurity scattering
    Magnetic impurity
    Residual resistivity
    Anderson impurity model
    Citations (0)
    Abstract A muffin‐tin impurity model for the scattering properties of substitutional impurities is applied to 3d transition metal impurities in Al. The relative potential between impurity muffin‐tin and host muffin‐tins is chosen in such a way that a sum rule for the scattering phase shifts is fulfilled to obtain selfconsistent screening of the impurity charge. Calculations of the change in the electronic density of states and residua, l resistivity are presented, which show a characteristic behaviour due to the fact that a virtual bound state is crossing the Fermi level of the host.
    Ionized impurity scattering
    Citations (10)
    We investigate the effect due to background impurities embedded in the region of two-dimensional electron gases to the magnetotransport. These impurities are achieved by homogeneously incorporating Si atoms in single quantum wells of high quality GaAs/AlGaAs heterostructures. Several materials were grown this way with different densities of Si atoms. At low temperature the mobility decreases monotonically with increasing impurity density. In materials with incorporated impurities, effects are observed with increasing temperatures. On the one hand, a minimum in mobility appears, marking a transition between scattering enhancement due to acoustic phonon and mobility enhancement due to impurity driven conductivity. The temperature at which the transition takes place decreases with increasing impurity density. On the other hand, the incorporated impurities induce a non-monotonic temperature dependence of the electron density. The magnitude of this variation rises with increasing impurity density. The theory of electron-electron interaction correction to the conductivity alone fails to explain our results.
    Ionized impurity scattering
    Electron Mobility
    Citations (0)
    Abstract Spin-dependent scattering is considered to be the origin of giant magnetoresistance in magnetic multilayers, although the role of bulk or interface defects is still under discussion. We present calculations of spin-dependent impurity scattering potentials as a function of the impurity position in a Co/Cu-multilayer. The calculations are performed within spin density functional theory using a Green function method (the tight binding Korringa-Kohn-Rostoker method). It is shown that the impurity potential depends strongly on the impurity position, which is reflected in local densities of states and local impurity moments. Furthermore, calculations of magnetic properties of impurity pairs at the interface are presented and compared with results for single impurities.
    Magnetic impurity
    Ionized impurity scattering
    Anderson impurity model
    Position (finance)
    Citations (5)
    The impurity-limited resistance in quasi-one dimensional nanowire structures is studied under the framework of the Landauer and the Lippmann-Schwinger theories. The charge polarity dependence of the impurity-limited resistance (mobility) under localized impurities with short-range scattering potential is theoretically clarified. We show that the impurity-limited resistance (mobility) could be modulated over three orders of magnitude by varying the axial separation of the ionized impurities, provided that the charge polarity of the impurities is opposite to that of carriers. The present results are consistent with recent experimental observations that the electron mobility in Junctionless-FETs is enhanced as the donor concentration becomes large, contrary to the usual trends found from the semi-classical calculations.
    Ionized impurity scattering
    Polarity (international relations)
    Electron Mobility
    Modulation (music)
    Citations (0)
    In this letter we present results for the mobility of electrons confined in a layered structure when the scattering of the confined carriers is dominated by ionized impurity scattering. In the size quantum limit, the mobility is found to decrease with the layer thickness in contrast to the situation where acoustic phonon scattering is dominant. In the latter case, the mobility is found to increase with the layer thickness. We have considered the effects of both background and remote impurities on the mobility of the confined carriers. The results which we have obtained are considerably different from those currently available in the literature.
    Ionized impurity scattering
    Electron Mobility
    Phonon scattering
    Carrier scattering
    Citations (23)
    The electronic properties of impurities are shown to limit the attainable maximum impurity concentration in semiconductors. The repulsive interaction between impurities due to (i) the Coulombic charge of ionized impurities and (ii) the increase of electronic energy at high doping concentrations can result in impurity segregation effects that limit the maximum achievable doping concentration. As an example, we consider the doping properties of Be, C, and Zn in GaAs. The characteristics of these impurities at extremely high concentrations agree with Monte Carlo simulations and molecular-dynamics calculations of impurity incorporation during crystal growth, which take into account the repulsive interaction between impurities.
    Ionized impurity scattering
    Citations (26)