Underlayer effect on structural and magnetic properties of Co₉₀Fe₁₀ thin films

Abstract

In the present study, the single layer Co 90 Fe 10 and X/Co 90 Fe 10 (X = Cu, Cr, Au, Ni 80 Fe 20 ) double layer films were investigated. Films were fabricated by DC magnetron sputtering at room temperature on Si substrates. In order to improve the soft magnetic properties of CoFe films, four different underlayers were examined. The coercivity values of the films were obtained by using a laboratory design magneto-optic Kerr effect (MOKE) magnetometry. Magnetic force microscopy and x-ray diffraction results show that the crystalline structure and magnetic domains of CoFe films are sensitive to the initial layer. It was seen that the soft magnetic properties of CoFe films were improved with underlayers. Particularly, the Au underlayer was effective in reducing coercivity H c from 37 to 5 Oe.

Tuning the Magnetic Properties of FeCo Thin Films through the Magnetoelastic Effect Induced by the Au Underlayer Thickness

“…Figure shows the room-temperature magnetization, M , versus magnetic field, H , in-plane for the easy and hard axis for all samples. The coercivity field for the thinner film ≈143 Oe is higher to the expected for FeCo alloys prepared by a classical sputtering method (50–100 Oe), concluding that a thin gold-underlayer can increase the H c . At the same time, for subsequent thicknesses, the coercivity field reflects a progressive decreasing, as shown in Table , which strongly suggests a tuning of the coercive field by the control of the underlayer thickness.…”