Thin films of iron-based chalcogenide superconductors FeSe0.92, with iron partially replaced (at least up to 10 at %) by elements such as cobalt, nickel, manganese, or copper, have been grown on the surface of \((10\bar 12)\) LaAlO3 crystals. Growth is performed by the laser ablation of a target prepared in the form of a ceramic pellet by high-temperature synthesis and the sintering of preliminarily pressed stoichiometric mixture of powders. Iron in these ceramics is replaced with an alloying metal by no more than 3 at %. The rest (7 at %) of the metal is in the form of precipitates of other phases. X-ray diffraction analysis of the grown films has shown that they are single-crystal and free of any precipitates of other crystallographic orientations and phases. This is evidence of the complete (10 at %) replacement of iron with a doping metal in the film structure. This circumstance indicates that the synthesis of components occurs more actively and completely during laser ablation (than in solid-phase chemical reactions) as a result of the transformation of multicomponent target material into plasma. Thus, one can fabricate film materials in a wider range of chemical compositions than in the form of solid-phase synthesized ceramics.
Thin films of FeSe0.92 and FeSe0.5Te0.5 iron chalcogenide superconductors and solid solutions containing these components in different ratios have been grown on the surface of LaAlO3 (10\(\bar 1\)2) crystals by pulsed laser deposition. Films of solid solutions have been deposited by simultaneous laser ablation from two targets of the FeSe0.92 and FeSe0.5Te0.5 stoichiometric compositions onto one substrate. An X-ray diffraction study of the film structure shows that the films grown are epitaxial and their lattice parameters regularly vary with the ratio of the deposited components, which was controllably varied by changing the ablation intensities from the targets.