Charge transfer, polarization, and relaxation effects on the Auger line shapes of Si.

Abstract

The Auger line shapes of Si are quantitatively interpreted noting particularly the core-hole screening effects as exhibited through charge transfer, polarization, and atomic relaxation. The ${\mathrm{KL}}_{1}$V, ${\mathrm{KL}}_{2}$,3V, and ${L}_{1}$${L}_{2}$,3V line shapes reflect a core-hole-screened density of states (DOS) consistent with the core hole in the final state of these processes. A DOS appropriate for the screened core hole is obtained by distorting the theoretical DOS for the ground state utilizing the Green's function for a tight-binding Hamiltonian and a central-cell potential. Comparison of the ${L}_{2}$,3VV and KVV line shapes reveal large differences. These differences are discussed in the context of surface effects, intrinsic and extrinsic plasmon losses, and final-state shakeoff. The ${L}_{2}$,3VV and KVV line shapes also suggest some distortion effects due to final-state hole correlation. The ${\mathrm{KL}}_{2}$,3${\mathrm{L}}_{2}$,3 line shape is interpreted in the context of similar line shapes for Na, Mg, Al, and P; all show plasmon losses and, except for P, initial-state shakeoff contributions.