Thin films of Fe1+δSe1−xTex (δ∼0.18 and x∼0.5) have been successfully grown on (100)-oriented single-crystalline SrTiO3 and LaAlO3 substrates by pulsed laser deposition. The crystal structure was characterized by x-ray diffraction and the superconducting properties by electrical resistivity measurements. X-ray diffraction analysis establishes the growth of films with c-axis orientation. Atomic force microscopy showed a smooth surface morphology for the films grown on SrTiO3 substrates. All the films are observed to be superconducting with a transition temperature, Tc of ∼8–14 K, depending on the deposition conditions. The deposition parameters were optimized to obtain good quality films with Tc comparable to that of the target material. The upper critical field shows a positive curvature near Tc unlike the opposite behavior observed in conventional superconductors.

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