LOW-ENERGY AUGER-ELECTRON SPECTROSCOPY OF IRON-OXIDE - OXIDATION OF ONE MONOLAYER OF IRON ON CU(100)

The peak shape of the iron M2,3VV Auger peak during the oxidation of one monolayer of iron on Cu(100) was studied. Peak shape analysis indicated that all iron is oxidised to gamma-Fe2O3 before oxygen adsorbs on the Cu(100) surface. The oxidation of iron probably proceeds at once from Fe0 to Fe3+ though initially adsorbing oxygen causes a different ratio between the cross transition and the auto-ionisation peak than later adsorbing oxygen.