Magnetic and spin-dependent transport properties of reactive sputtered epitaxial Ti1−xCrxN films

• Published in: Acta materialia Vol. 60; no. 9; pp. 3690 - 3697
• Main Authors: Duan, X.F., Mi, W.B., Guo, Z.B., Bai, H.L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-05-2012; Elsevier
• Subjects: Applied sciences; Carrier density; Cross-disciplinary physics: materials science; rheology; Curie temperature; Electrical properties; Electrical resistivity; Epitaxy; Exact sciences and technology; Ferromagnetic materials; Localization; Magnetic thin films; Magnetoresistance; Magnetoresistivity; Materials science; Metals. Metallurgy; Methods of deposition of films and coatings; film growth and epitaxy; Nitrides; Physics; Position (location); Production techniques; Sputtering; Surface treatment; Nitrides; Electrical properties; Magnetoresistance; Magnetic thin films; Sputtering; Magnetic material; Diffusion; Thin film; Magnetic properties
• ISSN: 1359-6454; 1873-2453
• DOI: 10.1016/j.actamat.2012.03.043

Reactive-sputtered epitaxial Ti1−xCrxN films are ferromagnetic in the range of 0.17⩽x⩽0.51 due to the Cr–N–Cr double-exchange interaction below the Curie temperature (TC). The TC first increases, then decreases as x increases, and a maximum of 120K appears at x=0.47. All of the films are metallic with a transition near TC. A resistivity minimum ρmin is observed below 60K in the films with 0.10⩽x⩽0.51 due to the effects of the weak localization and electron–electron interaction. The negative magnetoresistance (MR) is caused by the double-exchange interaction below TC and the weak localization can also contribute to MR below Tmin where ρmin appears. The x-dependent electron carrier densities reveal that the ferromagnetism is not from the carrier-mediated mechanism. The anomalous Hall resistivity follows the relation of ρxyA∝ρxx2, which is from the side-jump mechanism.