Monte Carlo Simulation of Elastic and Inelastic Scattering of Electrons in Thin Films:1. Valence Electron losses

AMonteCarlocomputerprogram which takesintoaccountboth elastic and inelastic scatteringof electrons has been set up.Inthe present paper the latteisr limited to valence electron losses. These are described through three modelms:oadified form of the Lindharddielectricfunctiontotakeintoaccountheenergygap,the plasmon-pole approximationtothedielectricfunctionandthe cross-sections forplasmonand single electron excitation simply joined at their intersection point. Calculations were performed for100keV electronsinsilicon,withthicknessvaryingfrom850to2550A,i.e.from1to3 total mean free paths. Thefirst two modelsgive practically the same resultswhile the third one is not good enough. The effectof the thickness on the transmitted energy spectrumis analysedfor the purpoosfethickness determination. Thiasnalysisis extended to the complete energy-angle spectrum to discriminate between the effects of plural elastic and inelastic scattering, in order to reconstruct thesingle inelastic scattering spectrum.