Ni-Zn ferrite films have been prepared by spraying a reaction solution of FeCl{sub}2 + NiCl{sub}2 + ZaCl{sub}2 (pH = 6.8) and an oxidizing solution of NaNO{sub}2 + CH{sub}3COONH{sub}4 + NH{sub}4OH (pH = 6.8-9.2) simultaneously onto rotating glass substrates at a substrate temperature of 90 ℃. The deposition rate increased with the pH value of the oxidizing solution, and a maximum deposition rate of 67 nm/min was attained at pH = 8.4. The film surface observed by scanning electron microscopy was smooth, and a high value of saturation magnetization M{sub}s = 482 emu/cm{sup}3 with a low value of coercivity H{sup}c = 17 Oe were measured. The film showed a high static permeability μ' = 70 and very high magnetic resonance frequency f{sub}r of about 900 MHz. The imaginary part of the permeability μ" was greater than 30 over a wide frequency range from 300 MHz to 3 GHz. Ni-Zn ferrite films prepared in this study should be useful not only for planar inductors but also as shielding materials for electromagnetic interference suppressions.
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