Thin magnetic films of Sm–Co nanocrystallites exploiting spin coating deposition

• Published in: Thin solid films Vol. 519; no. 19; pp. 6290 - 6296
• Main Authors: Saravanan, P., Ramana, G. Venkata, Rao, K. Srinivasa, Sreedhar, B., Perumal, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 29-07-2011; Elsevier
• Subjects: Annealing; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Exact sciences and technology; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Magnetic films; Magnetic properties; Magnetic properties and materials; Magnetic properties of monolayers and thin films; Magnetic properties of surface, thin films and multilayers; Magnetization; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanocrystallites; Nanocrystals; Nanoscale materials and structures: fabrication and characterization; Other topics in nanoscale materials and structures; Physics; Precursors; Samarium–cobalt; Silicon dioxide; Sol–Gel; Spin coating; Theory and models of film growth; Thin magnetic films; X-ray diffraction; Nanocrystallites; Thin magnetic films; Spin coating; X-ray diffraction; Samarium–cobalt; Sol–Gel; Magnetic properties; Nucleation; Annealing temperature; XRD; Cobalt; Precursor; Magnetic thin films; Thin films; Coercive force; Samarium; Thermal annealing; Sol-gel process; Crystal structure; Crystalline phase; Magnetization; Layer thickness; Samarium-cobalt; Spin-on coating; Spinning; Nanostructured materials; Sol―Gel
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2011.03.131

Thin magnetic films of Sm–Co nanocrystallites on SiO
2 substrate were fabricated using spin coating deposition. In a typical synthesis, precursor of Sm–Co oleate complex was spin coated onto a SiO
2 substrate in the form of precursor films and subsequently they were subjected to reductive annealing at 773
K for 2
h, so as to crystallize Sm–Co phase in the films. It has been found that the reductive annealing temperature (573–773
K) played a critical role on the nucleation and formation of Sm–Co crystalline phases; while the spinning speed (3000–5000
rpm) has a significant effect in controlling the film thickness, which in turn affects the particle diameter, inter-particle distance and packing density of the Sm–Co nanocrystallites. Coercivity values of 27.9, 23.9 and 18.7
kA⋅m
−
1
and magnetization values of 2.89, 2.51 and 2.21
×
10
−
6
A⋅m
2 were achieved for the Sm–Co films with thicknesses of 345 (3000
rpm), 264 (4000
rpm) and 162
nm (5000
rpm), respectively. Further, these hard magnetic properties could be significantly improved by subjecting the Sm–Co films to post-annealing at 873
K.