Influence of V2O5 on the Magnetic Properties of Nickel-Zinc-Copper Ferrites

Nickel-zinc-copper ferrites are used for manufacturing multilayer chip inductors. They can also be used to realize integrated transformers but in this case, low core losses are also required. Their sintering temperature (around 900degC) is low but not enough to allow co-firing with conventional silver inks for making the internal conductor. Their sintering temperature can be lowered by using sintering aids like low melting point oxides: B₂O₃, Bi₂O₃ or V₂O₅. Previous papers showed that V₂O₅ was effective for lowering the sintering temperature but only for low permeability ferrites (mu < 30) and for low power applications. In this paper, we report the effect of V₂O₅ upon the magnetic properties of some NiZnCu ferrites with permeability higher than 300 and with low core losses.