Straggling and extreme cases in the energy deposition by ions in submicron silicon volumes

The variations in the energy deposited by ions in thin silicon layers and submicron volumes are calculated using Monte Carlo and convolution methods. For the δ-electron spectra we use a detailed spectrum, considering solid state effects. For each ion, the energy it deposits in a sensitive (to single events) volume (SV) is found by subtracting the energy of the δ-electrons when escaping the SV from the energy the ion loses in the SV. The behavior of the resulting straggling functions is studied in detail as function of the SV shape and angle of incidence of the ion beam. They are used for estimating the probabilities of single events, in particular those due to rare high energy deposition events. The latter are compared with the probability for events due to nuclear reactions of the ion with the electronic material nuclei.