Effect of Argon Annealing Time on Properties of Fe(Se,Te) Thin Films

Abstract

Abstract: As one of the iron-based superconducting thin films, Fe(Se,Te) thin films have the simplest crystal structure, fewer elements and easy to be synthesized, which is conducive to the study of superconductivity mechanism and has potential technical applications. In this paper, Fe(Se,Te) thin films were prepared by magnetron sputtering on CaF₂ single crystal substrates at 320 ℃ and annealed in argon atmosphere. The effects of annealing time on the crystal structure, surface morphology, composition and electrical transport characteristics of Fe(Se,Te) thin films were investigated. The results show that the crystallinity of Fe(Se,Te) thin films is good, annealing is helpful to eliminate FeSe phase in the thin films, lattice constant c is not sensitive to annealing, and the grain size of the thin films increases after annealing. The composition of Fe(Se,Te) thin films is different from the nominal composition of target material, and the longer the annealing time, the denser the particles on the Fe(Se,Te) films surface. The resistance of Fe(Se,Te) thin films decreases with the increase of temperature, showing semiconductor characteristics, and the resistance increases obviously after 3 h annealing.

Key words: Fe(Se,Te) thin film, magnetron sputtering, argon annealing, electrical transport characteristic, iron-based superconducting thin film

CLC Number:

LUO Lulin, ZHANG Jie, YANG Xinsheng, ZHAO Yong. Effect of Argon Annealing Time on Properties of Fe(Se,Te) Thin Films[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2022, 51(4): 660-665.

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