Magnetic properties of NiCuZn ferrite thin films prepared by the sol-gel method

Abstract

Ni_0.4Cu_0.2Zn_0.4Fe₂O₄ thin films were fabricated on Si substrates by using the sol-gel method and rapid thermal annealing (RTA), and their magnetic properties and crystalline structures were investigated. The samples calcined at and above 600 °C have a single-phase spinel structure and the average grain size of the sample calcined at 600°C is about 20 nm. The initial permeability μ _i, saturation magnetization M _s and coercivity H _c of the samples increase with the increasing calcination temperature. The sample calcined at 600°C exhibits an excellent soft magnetic performance, which has μ _i=33.97 (10 MHz), H _c=15.62 Oe and M _s=228.877 emu/cm³. Low-temperature annealing can enhance the magnetic properties of the samples. The work shows that using the sol-gel method in conjunction with RTA is a promising way to fabricate integrated thin-film devices.

Keywords

Ni_0.4Cu_0.2Zn_0.4Fe₂O₄ thin films / sol-gel method / rapid thermal processing / magnetic properties

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