Study of ion tracks by micro-probe ion energy loss spectroscopy

Structural changes of ion-irradiated polymers can be visualized by wet chemical etching. In this process, the latent tracks can be developed into pores of various shapes and sizes. To nondestructively determine the 3D structure (spatial density distribution) of an individual pore, a new approach, utilizing energy loss spectroscopy of ions transmitted through a pore and its vicinity has been tested. To evaluate the density alterations in the pore, a new Monte Carlo simulation code was developed. The code calculates residual energy of ions passing through the pore of a selected shape and compares the data with the measured energy spectra. The best fit determines the appropriate geometrical parameters of the pore. In the paper, details of a tomographic examination of a single pore in a thin polymer foil are presented and discussed for the first time.