Electroplated and screen-printed magnetic materials applicable to micromachined magnetic devices

Abstract

In this research, electroplated magnetically isotropic and anisotropic soft alloys and screen-printed soft ferrites applicable to micromachined micromagnetic devices are fabricated and characterized using in-situ measurement techniques. Appropriate magnetic materials and deposition methods, such as electroplating and screen-printing techniques, are examined and material test structures are fabricated. Following material characterization, micromachined inductors with three-dimensional structure are fabricated to determine the usefulness of the magnetic materials and deposition methods. The micromachined inductor is a key component and geometry for realizing micromagnetic devices such as amplifiers, filters, sensors, and actuators. Three different material types are studied in this work Electroplated magnetically isotropic soft alloys, permalloy (Ni80Fe20), orthonol (Ni50Fe50), and amorphous cobalt-iron-copper (CoFeCu) alloys, are studied, followed by electroplated magnetically anisotropic soft alloys of permalloy (Ni80Fe20) and supermalloy (NiFeMo), which have magnetically easy and hard axes. Finally, screen-printed polymers filled with soft ferrite (NiZn and MnZn) powders, are fabricated and characterized.