The effect of rare earth impurities on the oxidation of chromium

Abstract

A systematic study has been made of the effects of Group III and rare earth impurities on the thermal oxidation of chromium. The elements were introduced by ion implantation. The oxidation properties and impurity behaviour were studied using alpha particle Rutherford backscattering, nuclear reaction analysis, CAMECA ion microprobe analysis, X-ray diffraction and scanning electron microscopy. Cr⁺ ion implantation was used to study radiation damage and annealing behaviour. For unannealed chromium the oxidation rate was found to be reduced by 60-90% by all the implanted species. Some evidence was found for a correlation with the mobility of the implanted species, X-ray measurements indicate the possible formation of a binary oxide.