Absolute energy calibration in Auger electron spectroscopy by using elastically backscattered primary electrons

Abstract

AbstractThe feasibility of an absolute energy calibration in Auger electron spectroscopy has been studied by using elastically backscattered primary electrons with an accuracy of 15 meV(σ) for the energy range 10–1200 eV. Our novel prototype cylindrical mirror analyser (CMA) was further improved for this work. An electron gun with a special tungsten cathode should present well‐defined characteristics of primary electrons of constant shape in the energy distribution, irrespective of the acceleration voltage. The effects caused by the Wehnelt bias, space charge and cathode temperatures were examined. Thus, for the proper setting of the Wehnelt bias and cathode temperature, an ‘iteration’ method (between higher and lower energies) using a precision calibrated primary accelerating power supply was employed to obtain the transfer coefficient of the CMA. This is a self‐consistent method with automatic correction for work functions. Furthermore, a poor energy resolution of the CMA would shift the peak position in a spectrum as the result of a convolution of the actual spectrum with the analyser function, particularly for higher energies. Such peak shifts were simulated using an experimental spectrum. Copyright © 2002 John Wiley & Sons, Ltd.