Tailoring the magnetic anisotropy and domain patterns of sputtered TbFeGa alloys

Abstract

We report the magnetic anisotropy and domain configuration of cosputtered TbFeGa alloys. The layers were deposited from two targets with compositions TbFe 2 and Fe 3 Ga, respectively. The structural and magnetic properties do not only depend on the composition but also on the growth conditions. Alloys with the same composition but deposited using a DC or a pulsed power source in the TbFe 2 target exhibit a different magnetic anisotropy. The perpendicular magnetic anisotropy, the size and topology of domain patterns can be tailored by changing the evaporation parameters of TbFe 2 . The width of the stripe domain increases from 235 to 835 nm when using the DC source in the TbFe 2 . We correlate this effect with Tb enrichment of the Tb x Fe! x phases present in the samples.

Evolution of the structural and magnetic properties of sputtered TbxFe73Ga27-x (7 at.% ≤ x ≤ 11 at.%) thin films upon the increase of Tb content

“…In our compounds the Tb content is higher than that solubility limit, and in agreement with those reports, we observe a (Fig. 1b) as reported in previous works in which much higher Tb dopings are introduced [24,25]. Therefore, the growth conditions proposed in this work enable to tune the structure of Tb x Fe 73 Ga 27-x (7 at.% x 11 at.%) thin films from two separate phases, related to FeeGa and TbeFe alloys, to one phase similar to TbFe 2 as the Tb content increases from 7 at.% to 11 at.%.…”

“…The peak at 2q~73.68 corresponds to the reflection (211) of Mo. In the samples studied in this work, it is observed a diffraction peak at 40.7 as also observed in previous works about TbeFeeGa compounds with a Tb content~10 at.% [24,25]. Although this peak is near the (110) of Mo, it is closer to that of the TbFe 2 being possible to correlate it to the latter structure (Fig.…”

“…Nevertheless, more studies are necessary to know the microstructure and magnetic behavior in each compositional range. In addition, it is of relevance the investigation of the effect of growth conditions as already indicated by previous works [25]. Here, we present an investigation about the magnetic behavior of Tb x Fe 73 Ga 27-x (7 at.% x 11 at.%) thin films obtained by cosputtering.…”

“…The targets have a diameter of 5 cm and a thickness of 0.3 cm. The deposition was performed in the oblique incidence, being the angle of incidence between each target and the substrate of about 25 and the distance between the targets and the substrate of 9 cm, i.e., smaller than in previous works [24,25]. Another difference in comparison to previous works is the use of a DC power source in the two targets.…”

“…In particular, l s shows an increase of~250% in (110)-textured polycrystalline alloys doped with a 0.3 at.% of Tb [23]. Besides, there have also appeared works about ternary TbeFeeGa compounds where another compositional range has been explored, Tb y Fe 100-x-y Ga x thin films with y between 9 and 10 at.% and x from 13 to 16 at.% obtained by cosputtering [24,25]. The magnetic anisotropy and the possibility to control it by means of the growth conditions have been the main goal of those studies.…”