Characteristic Energy Loss Spectra of II-VI Compounds

Characteristic electron energy loss spectra of some II-VI compounds, ZnS, ZnSe, ZnTe, CdS and CdSe, were measured up to about 25 eV by transmission of 40 keV electrons and compared with the energy loss function -Im[ ε (ω) -1 ] calculated from optical measurements. Good agreements between them were found in the peaks from 0 eV to about 13 eV. Some of the characteristic energy losses were explained; losses at about 11∼12 eV are due to the excitations of the valence electron plasmons, those at about 14 eV and those at about 17 eV are due to the excitations of cation d electrons and of anion s electrons respectively.