Electro-infiltrated nickel/iron-oxide and permalloy/iron-oxide nanocomposites for integrated power inductors

Magnetic nanocomposite materials are of interest for applications including power inductors and transformers, where a combined large bandwidth, low loss, and relatively high permeability are desired. This work demonstrates the fabrication of nickel/iron-oxide nanocomposites, up to similar to 3 mu m thick, and permalloy/iron-oxide nanocomposites, up to similar to 1 mu m thick, using an electro-infiltration process, whereby the voids in an iron-oxide nanoparticle film are filled with electroplated metal. Measurements show that the magnetic nanocomposites exhibit hybrid magnetic properties: modestly high permeability and saturation attributed to the metal matrix phase, but with an increased bandwidth attributed to the iron-oxide inclusion phase. At 10 MHz, the nickel/ironoxide nanocomposite material exhibits a relative permeability of similar to 23, with a loss tangent around 0.1; the permalloy/iron-oxide nanocomposite exhibits a relative permeability of similar to 136, with a loss tangent around 0.15.