Evaluation of temperature‐dependent surface chemistry in Zr ₂ Fe and ZrVFe via X‐ray photoemission spectroscopy

Abstract

Abstract The near atomic composition and the character of chemical bonds in two non‐evaporable gettering alloys have been investigated via core level (Zr 3d; Fe 2p; V 2p; O 1s; C 1s) XPS ( h v = 1253.6 eV). The samples have been measured in UHV after in‐air fracturing and various annealing steps (up to 850 °C). For T > 400 °C a progressive and sizeable decrease of the near surface C content along with an increase in the Zr concentration is observed in both alloys. An annealing‐induced Zr enrichment at the surface is found, the metallic atomic concentrations being permanently far from the nominal bulk stoichiometry. The annealing induces a strong evolution in the chemical bonds, the metallic species being completely oxidized in‐air fractured samples while progressively emerging a metallic character at increasing temperatures. Surface metallization proceeds faster in Zr 2 Fe than in the V‐containing getter.