Inelastic mean free path of H+ and He+ with the energy of similar to 100 keV in carbon film

The energy loss distributions of H+ and He+ with similar to 100 keV transmitted through carbon films with a thickness of similar to 6 nm have been measured by means of high-resolution (similar to 30 eV) ion energy loss spectroscopy. The zero energy loss peaks have been observed. The presence and effect of pinholes in films is inferred from the H-2(+) transmission yield. Assuming that the intensity ratio of the zero energy loss peak over the sum of this peak and the main energy loss peak follows an exponential decrease with the film thickness, the inelastic mean free path was derived as 0.6 and 0.9 nm for H+ and He+ at 100 keV and these values are compared with the experimental values for equivelocity electrons and also with the calculated values for equivelocity electrons, positrons and protons.