Hole mobility in SiGe alloys from first principles.

ORAL

Abstract

First principles density functional theory is used to calculate the mobility of holes in Si$_{1-x}$Ge$_{x}$ alloys as a function of alloy composition. The alloy host is modelled within the virtual crystal approximation (VCA) using supercell techniques. The scattering matrix for carrier scattering in the presence of a Ge or Si substitutional atom in the VCA lattice is determined from the resultant energy splitting in the valence bands. The effect of the spin-orbit interaction is included in these calculations. The mobility is obtained from the scattering rate using the Boltzmann transport equation in the relaxation time approximation.

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Authors

  • Sian Joyce

  • Felipe Murphy-Armando

    • Tyndall National Institute, Lee Maltings, Prospect Row, Cork, Ireland

  • Stephen Fahy

    • Department of Physics, University College Cork, Ireland
    • Tyndall National Institute, University College Cork
    • Tyndall National Institute and Dept. of Physics University College Cork, Ireland
    • Department of Physics and Tyndall National Institute, University College, Cork, Ireland