Highly Crystalline Y₃Fe₅O₁₂ Thin Films by Cictric Spray Pyrolysis

Abstract

Ethylene glycol solution of mixed-metal Y(III)-Fe(III) citric complexes has been used as a starting material for a spray pyrolysis deposition of Y₃Fe₅O₁₂ (YIG) thin films on silica and on single crystal Y₃Al₅O₁₂ (YAG) substrates heated up to 500°C. O₂ was used as a carrier gas. A post-deposition thermal annealing at 800–1100°C was applied. Films of 0.1–1.2 μm in thickness were obtained. Their composition, binding energies, crystal structure, morphology, and magnetic properties were studied. Phase homogeneous polycrystalline or highly textured YIG films were obtained on silica or YAG substrates at annealing temperatures of 860° and 960°C, respectively. The crystallite grain sizes of both type of layers were ∼80 nm along the (400) plane. A columnar structure of the films with the column diameter of 400–500 nm might be supposed following the atomic force microscopy data. Saturation and permanent magnetizations along the easy axis of 1545 Gs and 816 Gs, respectively, and coercive force along the same axis of 4 Oe were measured.