Elastic electron reflection for determination of the inelastic mean free path of medium energy electrons in 24 elemental solids for energies between 50 and 3400 eV

Elastic electron backscattering coefficients have been measured for 24 elem ental solids (Ag, Al, Au, Be, Bi, C, Co, Cu, Fe, Ge, Mg, Mn, Mo, Ni, Ta, Te , Ti, Pb, Pd, Pt, Si, V, W and Zn) for energies between 50 and 3400 eV. Val ues for the electron inelastic mean free path (IMFP) were derived from the experimental intensities on the basis of a simple physical model that accou nts for bulk elastic and inelastic scattering only. The internal consistenc y of the data set and the evaluation procedure is satisfactory for energies > 150 eV. For energies greater than or equal to 200 eV the IMFP values wer e found to be well described by the Bethe equation for inelastic scattering , as found earlier by analysis of optical scattering data with the aid of t he linear response theory [Surf. Interface Anal. 21 (1994) 165]. We also co mpare the parameters beta (being related to the total dipole matrix element s for inelastic scattering) and gamma (determining the details of the energ y dependence of the IMFP) that appear in the Bethe equation with correspond ing results based on optical data. Both parameters were found to agree well with the earlier analysis by Tanuma et al. [Surf. Interface Anal. 21 (1994 ) 165] within the statistical accuracy of the present analysis. Experimenta l data on the recoil energy in elastic scattering were also analyzed and co mpared with detailed results of Monte Carlo simulations of this phenomenon. The recoil energies are correctly predicted to within 10% by the single de flection model based on the Rutherford cross section. (C) 2001 Elsevier Sci ence B.V. All rights reserved.