Eur. Phys. J. D (2016) 70: 248
https://doi.org/10.1140/epjd/e2016-70277-3

Regular Article

Stopping cross sections of protons in Ti, TiO₂ and Si using medium energy ion scattering

Department of Physics and Astronomy, University of Western Ontario, London, Ontario, N6A 3K7, Canada

^a e-mail: mbrockle@uwo.ca
^b Currently at National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada.

Received: 19 April 2016
Published online: 22 November 2016

Abstract

Stopping cross sections of protons in Ti, Si, and TiO₂ films in the energy range 50–170 keV were determined from medium energy ion scattering (MEIS) spectra by an iterative procedure. The energy loss of protons was investigated for pure Ti and Si films, deposited by molecular beam epitaxy (MBE) onto n-Si(100) and diamond-like carbon (DLC) substrates respectively. Consecutive annealing of Ti at 200 °C in O₂ resulted in stoichiometric TiO₂ thin-films. Thickness and composition of the films and the interfacial properties were determined using Rutherford backscattering spectroscopy (RBS), MEIS, and X-ray photoelectron spectroscopy (XPS). Calculated stopping cross sections of Ti, Si, and TiO₂ in the range of energies were compared with the commonly used SRIM2003 values. For Ti and Si, SRIM2003 values appear to be overestimated over the entire energy range. The new stopping cross sections explain deviations from previously reported values for SrTiO₃. We note that the stopping cross sections of O in a gaseous phase, used in Bragg’s rule calculations, cannot be applied for accurate quantitative ion beam analysis in solid compounds in the medium ion energy range.