Interface Excitation Effect in Reflection Electron Energy Loss Spectroscopy

ABSTRACT We performed reflection electron energy loss spectroscopy (REELS) measurements with electron energies between 500 and 2000 eV for three samples consisting of a film of SiO , with thickness of 1.2, 2.1, or 100 nm, deposited on a Si substrate. In parallel, we conducted Monte Carlo (MC) simulations in the same conditions including surface excitations and also interface excitations occurring at the SiO /Si interface, calculated from the local inverse inelastic mean free path (local‐IIMFP) model. Our experimental and theoretical results show an energy loss peak at about 8 eV, which is a clear signature of the SiO /Si interface effect. Moreover, the agreement between simulated and experimental spectra is very good in a range of energy loss of 50 eV. We thus confirm the existence of the interface effect, and we also demonstrated the validity of the local‐IIMFP model.