K-SHELL AUGER TRANSITIONS INDUCED BY MO X-RAYS

For exciting K-Auger transitions of elements with atomic number between 13 and 26, Mo x-rays (Mo bremsstrahlung + Mo L(alpha, beta) from a high voltage (max. 30 kV) source were used. High-resolution K-Auger spectra were measured by the help of a high luminosity hemispherical electron spectrometer. Spectral intensities obtained using the Mo x-ray source are compared to the respective intensities measured using an Al anode and source parameters usual for electron spectrometers. The attainable gain in Auger yields is between 2 and 15 for most elements investigated and reaches a factor of 20.5 in the case of P KLL. Optimum conditions of K-Auger excitation (regarding the atomic number region mentioned) are also discussed. As an example for applications, the phosphorus K-Auger parameter has been determined for GaP, taking an advantage of the presence of the P Is (Mo Lalpha) photoelectron line in the spectra excited by Mo x-rays. The higher analytical sensitivity, attainable by measuring Mo x-ray-induced P KLL Auger electrons compared to the sensitivity of the conventional XPS (Al Kalpha excited P 2p), is demonstrated in the case of a phosphoric compound (corrosion inhibitor) adsorbed on a polycrystalline Fe surface.