In Operando imaging Surface Acoustic Waves in Aluminum Scandium Nitride thin film

Our study focuses on new magnetoelectric sensors, enhancing sensitivity to bio-magnetic frequencies. Surface Acoustic Wave (SAW) sensors utilizing Aluminum Scandium Nitride (AlScN) as the piezoelectric material show great potential for improving sensor sensitivity. Finite Element Method (FEM) simulations indicate that these systems can excite surface confined or bulk acoustic modes, with different strain profiles. The distribution of shear and transverse components depend on the mode. We aim to deploy full-field X-ray diffraction microscopy (FF-XRD) to image periodic variations in lattice spacing. This is achieved by applying a high-frequency signal via interdigital transducers to induce standing SAWs with μm scale, generating a stationary strain pattern. The high resolution and wide-field of FF-XRD make it well-suited for this analysis. The understanding of the strain profile combined with other techniques are essential to study the shear component, improving the sensor sensitivity.