Evaluation of the contribution fraction of close collision to the backward electron emission induced by He+ ion

Abstract

Electron emission for He+ incident on solid surfaces of C, Cu and Al was simulated with the MonteCarlo method.The backward electron emission yields are calculated.The contribution fraction of electrons emitted by close collision to the total backward emission yield is evaluated with this code, and contribution fraction is 0.5,0.55 and 0.42 for C, Cu and Al, respectively. The effect of highenergy (E＞100eV) δ electrons on the backward electron yield is also considered in detail, and only those δ electrons with an energy of a few hundred eV plays an important role in the backward electron emission. For C, δ electrons will affect the behaviour of electron emission yield near the maximum electronic stopping power. Results of yield obtained are compared with experimental data of other authors, and a good agreement is found.