V2O5도핑된 NiCuZn 페라이트로 제조된 칩인덕터에서의 Ag/Cu 석출

Abstract

The purpose of this study is to investigate the effect of V2O5 addition on the Ag and Cu precipitation in the NiCuZn ferrite layers of 7.74.51.0 mm sized multi-layer chip inductors prepared by the screen printing method using 0~0.5 wt% V2O5-doped ferrite pastes. With increasing the V2O5 content and sintering temperature, Ag and Cu oxide coprecipitated more and more at the polished surface of ferrite layers during re-annealing at 840℃. It was thought that during the sintering process, V dissolved in the NiCuZn ferrite lattice and the Ag-Cu liquid phase of low melting point was formed in the ferrite layers due to the Cu segregation from the ferrite lattice and Ag diffusion from the internal electrode. During re-annealing at 840℃, the Ag-Cu liquid phase came out the polished surface of ferrite layers, and was decomposed into the isolated Ag particles and the Cu oxide phase during the cooling process.