Magnetic properties of electroplated nano/microgranular NiFe thin films for rf application

Abstract

A granular NiFe thin film with large in-plane magnetic anisotropy and high ferromagnetic-resonance frequency developed for radio-frequency integrated circuit (IC) applications is presented. During the deposition, three-dimensional (3D) growth occurs, yielding NiFe grains (φ~1.0 μm). Nanonuclei (φ~30-50 nm) are observed in single NiFe grains by atomic-force microscopy (AFM). The in-plane magnetic anisotropy is estimated to be ~50 mT. The frequency-dependent complex permeability is extracted. By taking the NiFe film as a magnetic core, solenoid-type inductors are fabricated and demonstrated and show a high operating frequency (~5.5 GHz) with a maximum quality factor (~3). © 2005 American Institute of Physics.