Ion fraction in the scattering of hydrogen on silicon surface

EVELINA A. GARCÍA; C. GONZÁLEZ PASCUAL; P. G. BOLCATTO; M. C. G. PASSEGGI; E. C. GOLDBERG

Physica Status Solidi C

WILEY-VCH Verlag GmbH & Co. KGaA

Lugar: Weinheim, Germany; Año: 2005 vol. 2 p. 3794 - 3797

We present a theoretical calculation of the resonant charge-exchange process occurring in H0 scatteringby Si(100)2 × 1 surfaces. In the atom-surface interacting system the core states of the surface atoms areincluded and the parameters of the Hamiltonian are calculated in an ab initio basis taking into account theextended features of the surface and the localized atom-atom interactions within a mean-field approximation.The density of states of the surface and sub-surface atoms are obtained from a molecular dynamic-densityfunctional theory in the local density approximation. An elastic binary collision is assumed to fix theprojectile trajectory, while the inelastic processes are determined by the interaction of the projectile atomwith all the surface atoms ’seen’ along its trajectory. The ion fractions are calculated by using the Green-Keldysh formalism to solve the time dependent process. The results, obtained as an average over differentpossibilities for the scattering center, reproduce the general trends of the experiment.