The spectroscopy of ion-induced photon emission and its application to quantitative surface analysis

Experimentally observed photon spectra produced by ion bombardment of transition elements Sc, Ti, V, Cr, Fe, Ni, and Cu and Zn with Ar⁺ ions are very similar to arc spectra of these same elements, with respect to relative intensities of lines observed. Standard spectrochemical analysis techniques, based on the assumption of local thermodynamic equilibrium in the arc plasma, have been applied to the spectra of the pure elements, to determine the effective arc temperature under relatively clean conditions and in an oxygen environment. These techniques have then been applied to the analysis of a stainless steel sample, again under relatively clean and oxygen environments. In order to explain differences in the $\text{Fe}\text{Cr}$ ratios measured, the behaviour of the intensities of the Fe and Cr emission has been investigated as a function of the oxygen background pressure. The results indicate that while analysis is possible the results depend on the oxygen background pressure.