Mnx Zny Fe3-x-y O4 films with a tailored microstructure were prepared by the spin-spray technique. The films were then heat treated (260 °C for 3 min) in a similar way to that of the reflow soldering process. The as-prepared and heat-treated films were studied for their structural, electrical, and magnetic properties. By using an oxidizing solution of C H3 COONa+ (N H4)2 C O3 +NaOH+NaN O2 (in contrast to that of C H3 COONa+NaN O2 in the conventional spin spray), Mn concentration (CMn) in the film was increased and a narrow columnar structure was obtained. This structure resulted in an increased surface resistivity (ρ s), thereby good noise suppressing properties even after the heat treatment. The films exhibited a high deposition rate of up to 63 nmmin with a good adhesion to the substrate. A slight decrease in the saturation magnetization (Ms) and increase in the uniaxial anisotropy field (Hk), and coercivity (Hc) were observed due to the heat treatment. The films also exhibited a decrease in imaginary permeability in the lower frequencies and the resonance frequency (fr) shifted to a higher frequency range. The film characteristics were as follows: Ms of 450-570 emu cm3, Hc of 18-45 Oe, Hk of 43-86 Oe, ρ s of 103 - 107 sq, initial permeability μ′ of 25-60, imaginary permeability μ″ of 20-38, and resonance frequency fr of 530-750 MHz. The films prepared at optimum condition exhibited reflection loss (S11) less than -10 dB and the transmission loss (Δ Ploss) of up to 50% at 10 GHz. Δ Ploss exhibited uniform distribution up to 1 GHz even after the heat treatment.
All Science Journal Classification (ASJC) codes
- 物理與天文學 (全部)