In the present work, formation of interfaces in the W/Be layered structures was studied using X-ray photoelectron
spectroscopy. Chemical composition and significance of the interfaces depending on the thickness and
ordering of beryllium and tungsten layers were investigated by means of the XPS spectra decomposition technique.
The formation of tungsten beryllides WBe2 and WBe12 at the W-on-Be and Be-on-W interfaces, respectively,
was revealed. The thickness of WBe2 beryllide does not depend on the thickness of a tungsten top layer,
whereas WBe12 thickness increases with increasing Be top layer thickness. Additionally, oxidation of a Be layer
under a thin W layer was established and possible mechanism underlying this process was proposed.