Quantitative analysis of reflection electron energy loss spectra to determine electronic and optical properties of Fe Ni alloy thin films
Abstract Electronic and optical properties of Fe Ni alloy thin films grown on Si (1 0 0) by ion beam sputter deposition were studied via quantitative analyses of reflection electron energy loss spectra (REELS) The analysis was carried out by using the QUASES XS REELS and QUEELS e( k o REELS softwares to determine the energy loss function (ELF) and the dielectric functions and optical properties by analyzing the experimental spectra. For Ni, the ELF shows peaks around 3.6, 7.5, 11.7, 20.5, 27.5, 67 and 78 eV. The peak positions of the ELF for Fe 28 Ni 72 are similar to those of Fe 51 Ni 49 even though there is a small peak shift from 18.5 eV for Fe 51 Ni 49 to 18.7 eV for Fe 28 Ni 72 A plot of n, k, e 1 and e 2 shows that the QUEELS e( k o REELS software for analysis of REELS spectra is useful for the study of optical properties of transition metal alloys. For Fe Ni alloy with high Ni concentration (Fe 28 Ni 72 e 1 and e 2 have strong similarities with those of Fe. This indicates that the presence of Fe in the Fe Ni alloy thin films has a strong effect.