Highly Sensitive Surface Acoustic Wave Magnetic Field Sensor Using Multilayered TbCo₂/FeCo Thin Film

Abstract

Over the last decades, the use of Surface Acoustic Waves (SAW) has emerged as a promising technology in many applications such as filters, signal processing but also sensors. We report the fabrication and the characterization of a SAW delay line magnetic field sensor using uniaxial multi-layered 14×[TbCo2(3.7nm)/FeCo(4nm)] nanostructured thin film deposited on Y36° Lithium Niobate (Figure 1a). The sensor shows an interesting dependency to a tunable bias magnetic field with different orientations relative to the easy axis. The obtained results are well explained using an equivalent piezo-magnetic model described in a previous work.

Keywords

• SAW sensor
• magnetostriction
• ∆E-effect
• multilayered thin film