TOF analysis of reflection of low-energy light ions from solid targets using coaxial impact collision ion scattering spectroscopy (CAICISS)

The energy spectra of He and D particles reflected from the Si(111)-root3 x root3 Sb surface at the angle of pi in the sub-keV regime have been studie d by means of a CAICISS system. The quantum efficiency of the microchannel plate for the particle detector in the CAICISS system has been determined a s a function of the kinetic energy from the comparison of the experimental peak intensity from Sb atoms in the sub-monolayer regime with the theoretic al one. The latter is calculated by use of the elastic scattering cross-sec tion derived from the Thomas-Fermi model of the screened Coulomb potential. The energy spectra of He particles backscattered from the Si(111) substrat e on incidence of 2 keV He+ ions have been also obtained by use of the quan tum efficiencies determined and compared with the theoretical ones calculat ed on the large angle single deflection model. (C) 2001 Elsevier Science B. V. All rights reserved.