화학공학소재연구정보센터
Applied Surface Science, Vol.258, No.10, 4764-4769, 2012
Surface morphology, structure, magnetic and electrical transport properties of reactive sputtered polycrystalline Ti1-xFexN films
Polycrystalline Ti1-xFexN films with different Fe atomic fractions (x) were fabricated by reactive facing-target sputtering. The lattice orientation changes from (2 0 0) to (1 1 1) with the increase of x, which makes the surface morphology evolve from spherical, triangular-pyramid-like islands to random-leafs-like ones. The films are ferromagnetic with a Curie temperature of higher than 305 K, and the saturation magnetization (M-s) is very small. Obvious asymmetric M-H curves are observed at low temperatures, and the shift of M-H curves decreases with the increasing temperature because of the relaxation of the pinned moments at low temperatures. All of the samples show semiconducting-like behavior with a mechanism of variable-range hopping at low-temperature range. Magnetoresistance (MR) is very small. The small M-s and MR can be explained by the facts that the interaction between Fe3+-N3--Fe3+ is antiferromagnetic superexchange coupling, and no double exchange exists in Fe3+-N3--Ti3+, which is different from that in the Cr-doped TiN films. (C) 2012 Elsevier B.V. All rights reserved.