Voltage Tunable RF Integrated Multiferroic Inductors with FeGaB/Al2O3 Multilayer Films

Abstract

As one of the three fundamental components for electronic circuits, inductors have been extensively used in a variety of applications. Voltage tunable capacitors have been widely used in many different circuit applications. However, voltage tunable inductors have not been readily available, which severely limits their applications. Lou and coworkers [1] have recently reported a new class of compact and power-efficient voltage tunable multiferroic inductors, which was based on a solenoid inductor with a multiferroic core which exhibited a large tunable inductance range of Lmax/Lmin=550%, together with 3_ enhanced quality factors and >10~100_ enhanced operation frequency range which is ideal for real applications. In this work, we report new RF multiferroic inductors based on integrated magnetic solenoid inductors with FeGaB/Al2O3 multilayer film [2] on 0.5mm thick ferroelectric (011) cut PMN-PT slab. Vector network analyzer based on RF probing system was used to implement the testing. Integrated magnetic inductors were epoxy bonded to PMN-PT slab for achieving voltage tunable multiferroic inductors. The inductor shows very good high frequency performance with a wide operation frequency range of 0.5~2.5GHz, in which the inductance is over 2nH and the peak quality factor is close to 20. The integrated magnetic inductor also showed an inductance value of about two times as that of the same size air core inductor. Under an applied voltage on the PMN-PT heterostructure, the inductance and quality factor can be both tuned through a strain mediated magnetoelectric coupling due to the change of E-field.