Thickness dependence of the L2,3 branching ratio of Cr thin films

We report the electronic structure of chromium (Cr) thin films depending on its thickness using two measures, total electron yield (TEY) and transmission yield mode. The Cr L edge X-ray absorption spectroscopy (XAS) spectrum shows strong thickness dependence with broader line widths observed for L2,3 edge peaks for thinner films. The white line ratio (L3/L2) was found to be 1.25 from the integrated area under each L3 and L2 peak and 1.36 from the ratio of the amplitudes of each L3 and L2 peak after the deconvolution. Additionally, we show that full-width at half-maximum (FWHM) at the L2 and L3 edges and the branching ratio of Cr change as a function of film thickness and these are discussed in detail. Using L2,3 resonance intensity variation as a function of film thickness we calculated the electron escape depth and X-ray attenuation length in Cr. Comparing our results with the literature, there was good agreement for the L3–L2 ratio although the detailed shape can show additional solid state and atomic effects.