Effect of Yttrium Addition on Structure and Magnetic Properties of Co60Fe20Y20 Thin Films

Abstract

In this paper, a Co60Fe20Y20 film was sputtered onto Si (100) substrates with thicknesses ranging from 10 to 50 nm under four conditions to investigate the structure, magnetic properties, and surface energy. Under four conditions, the crystal structure of the CoFeY films was found to be amorphous by an X-ray diffraction analyzer (XRD), suggesting that yttrium (Y) added into CoFe films and can be refined in grain size and insufficient annealing temperatures do not induce enough thermal driving force to support grain growth. The saturation magnetization (MS) and low-frequency alternate-current magnetic susceptibility (χac) increased with the increase of the thicknesses and annealing temperatures, indicating the thickness effect and Y can be refined grain size and improved ferromagnetic spin exchange coupling. The highest Ms and χac values of the Co60Fe20Y20 films were 883 emu/cm3 and 0.26 when the annealed temperature was 300 °C and the thickness was 50 nm. The optimal resonance frequency (fres) was 50 Hz with the maximum χac value, indicating it could be used at a low frequency range. Moreover, the surface energy increased with the increase of the thickness and annealing temperature. The maximum surface energy of the annealed 300 °C film was 30.02 mJ/mm2 at 50 nm. Based on the magnetic and surface energy results, the optimal thickness was 50 nm annealed at 300 °C, which has the highest Ms, χac, and a strong adhesion, which can be as a free or pinned layer that could be combined with the magnetic tunneling layer and applied in magnetic fields.

Studying the Effects of Annealing and Surface Roughness on Both the Magnetic Property and Surface Energy of Co60Fe20Sm20 Thin Films on Si(100) Substrate

“…Conversely, rougher surfaces exhibit higher carrier conductivity, leading to a reduction in electrical resistance. The comparison with other designated materials can be seen in Table 1, including Cobalt Iron Ytterbium (CoFeYb) and Cobalt Iron Yttrium (CoFeY), deposited on Si(100) substrates [55,56]. The information presented in Table 1 highlights that the maximum χac in the current research is lower than observed in Co60Fe20Yb20 and Co60Fe20Y20 materials.…”

Co40Fe40Y20 Nanofilms’ Structural, Magnetic, Electrical, and Nanomechanical Characteristics as a Function of Annealing Temperature and Thickness

“…Compounds are formed by combining rare-earth elements and transition metals such as iron and cobalt, and it is worthwhile to explore the performance of the resulting compounds. CoFeY alloys are frequently utilized in the magnetic-recording-head sector for write poles, yokes, and shields [18][19][20]. In more recent nanofilm literatures, the effects of thickness and annealing temperature on characteristics have been investigated [21,22].…”