Vanadium trapped by oblique nano-sheets to preserve the anisotropy in Co–V thin films at high temperature

Favieres, C. ; Vergara, J. ; Magén, C. (Universidad de Zaragoza) ; Ibarra, M.R. (Universidad de Zaragoza) ; Madurga, V.

Resumen: In this study, oriented nano-sheets generated during the growth of cobalt-rich Co–V and Co–Zn thin films induced a large anisotropy in the magnetic and transport properties. The regular nano-sheets were tilted 52–54 deg. with respect to the substrate plane, ˜ 3.0–4.0 nm thick, ˜ 30–100 nm wide, and ˜ 200–300 nm long, with an inter-sheet distance of ˜ 0.9–1.2 nm. In spite of the different microstructures of the two kinds of samples where the Co–V films were amorphous, whereas the Co–Zn films showed a growth of Zn nanocrystals, the oblique nano-sheet morphology conferred noticeable shape anisotropy to both specimens. This anisotropy resulted in an in-plane uniaxial magnetic anisotropy. The changes in the nano-morphology caused by thermal treatments, and hence in their anisotropic properties, were studied. While the Co–V samples retained or increased their magnetic and transport anisotropies, this anisotropic behavior vanished for the annealed Co–Zn films. High resolution transmission electron microscopy, HRTEM, including chemical analysis at the nano-scale, and the dependence of the anisotropic resistance on temperature allowed to establish the nature and the activation energy spectra of the atomic relaxation processes during heating. These processes displayed a single peak at 1.63 eV for the Co–V and two peaks at 1.67 and 2.0 eV for the Co–Zn. These spectra and their singularities were associated to the changes induced in the nano-morphology of the films by thermal treatments. The Co–V films retained their nano-sheet morphology almost up to 500 ºC; the Co–Zn films lost their nano-sheets at 290 ºC. The thermal stability exhibited by the Co–V films makes them useful for applications in ultra high frequency, optical, magnetostrictive and magneto-electric devices.

Idioma: Inglés

DOI: 10.1016/j.jallcom.2022.164950

Año: 2022

Publicado en: JOURNAL OF ALLOYS AND COMPOUNDS 911 (2022), 164950 [12 pp.]
ISSN: 0925-8388

Factor impacto JCR: 6.2 (2022)

Categ. JCR: METALLURGY & METALLURGICAL ENGINEERING rank: 8 / 79 = 0.101 (2022) - Q1 - T1
Categ. JCR: CHEMISTRY, PHYSICAL rank: 45 / 161 = 0.28 (2022) - Q2 - T1
Categ. JCR: MATERIALS SCIENCE, MULTIDISCIPLINARY rank: 91 / 343 = 0.265 (2022) - Q2 - T1

Factor impacto CITESCORE: 10.9 - Materials Science (Q1) - Engineering (Q1)

Factor impacto SCIMAGO: 1.079 - Materials Chemistry (Q1) - Metals and Alloys (Q1) - Mechanics of Materials (Q1) - Mechanical Engineering (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E26
Financiación: info:eu-repo/grantAgreement/ES/MINECO/MAT2017-82970-C1
Financiación: info:eu-repo/grantAgreement/ES/MINECO/MAT2017-82970-C2-R

Tipo y forma: Article (Published version)

Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)