Magnetoelectric FeCoBSi/PVDF bilayers

In Magnetoelectric composites magnetostrictive and piezoelectric materials are combined in a way that changes in the dimension of the magnetostrictive material by an external magnetic field will lead to a measurable polarization change of the piezomaterial. It was already demonstrated that laminates fabricated by gluing of a FeCoBSi foil to a PVDF (polyvinylidene fluoride) foil provide a fairly high magnetoelectric response, but downsizing and integration into devices is rather complicated. To avoid these problems and to achieve a better mechanical coupling at the metal-polymer interface we deposited the FeCoBSi directly onto a piezoelectric PVDF foil by DC magnetron sputtering. An in situ applied magnetic bias field was used to improve the magnetic field direction sensitivity. The influence of the substrate preparation, sensor design and sputter parameters on the magnetoelectric output signal will be discussed.