Towards Wafer Scale Inductive Determination of Magnetostatic and Dynamic Parameters of Magnetic Thin Films and Multilayers

We investigate an inductive probe head suitable for noninvasive characterization of the magnetostatic and dynamic parameters of magnetic thin films and multilayers on the wafer scale. The probe is based on a planar waveguide with rearward high frequency connectors that can be brought in close contact to the wafer surface. Inductive characterization of the magnetic material is carried out by vector network analyzer ferromagnetic resonance. Analysis of the field dispersion of the resonance allows the determination of key material parameters such as the saturation magnetization M-s or the effective damping parameter a(eff). Three waveguide designs are tested. The broadband frequency response is characterized and the suitability for inductive determination of Ms-s and a(eff) is compared. Integration of such probes in a wafer prober could in the future allow wafer scale in-line testing of magnetostatic and dynamic key material parameters of magnetic thin films and multilayers.