Oxide dispersion hardened Mo thin films for high-temperature electrode applications

A new approach for the preparation of oxide dispersion hardened (ODS) Mo thin films is introduced. The 100 nm thick Mo based films were deposited on thermally oxidized Si substrates by magnetron sputtering from two different Mo-La 2 O 3 composite targets with 0.7 or 2.1 weight% La 2 O 3 . Pure Mo films served as a reference. The samples were annealed at 800 ° C or at 875 ° C for 24 h in high vacuum. Phase formation, morphology and electrical resistivity were analyzed by X-ray diffraction, scanning and scanning transmission electron microscopy and the van der Pauw method. The presence of La in the grown films was verified by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The results proved a successful transfer of La species from the composite targets into the grown film by the sputtering process, which led to the desired hardening of the film. There was a direct correlation between the content of La 2 O 3 in the target and its content in the grown film correlated with a systematic change of the physical properties. The suitability of the proposed approach was successfully demonstrated. • ODS Mo thin films are sputter-deposited from Mo-La 2 O 3 composite targets. • Films sputtered from targets with different amount of La 2 O 3 are compared. • Phase formation, electrical resistivity and morphology of the films are analyzed. • La 2 O 3 is successfully transferred from the target to the grown films. • A direct correlation between the amount of La 2 O 3 and film properties is observed.