Selective chemical sensor for liquid specimens based on lithium tantalate surface acoustic wave devices

We report in this paper the fabrication and characterization of a 121 MHz delay-line SAW device selective chemical sensor micro-fabricated on 36° rotated Y-cut X-propagating LiTaO3. A custom designed test fixture was manufactured for RF measurements. The proof of the sensor concept was based on detection of high molecular weight targets in liquid samples. Thus, the antigen-antibody label-free interaction was studied by monitoring the variation of the angle phase of SAW sensor with the concentration of some target biological analyte.