SH-SAW taste sensor based on acoustoelectric interaction

Abstract

This paper aims at discussing an application of SH-SAW devices on 36° rotated Y cut, X-propagating LiTaO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> to a taste sensor for identifying liquid samples. Theoretical sensor sensitivity for the acoustoelectric interaction with a liquid-loading on the SAW propagation surface was derived. The results strongly suggested that by employing different center frequency SH-SAW devices, the sensor can recognize many liquid samples without coating materials. In the experiment, we fabricated a taste sensor consisting of three SH-SAW devices at the center frequencies 30, 50, and 100 MHz, respectively. Identification of samples, 11 kinds of fruit juices, was achieved by classification in principal-component analysis and discriminant analysis. Since the SH-SAW sensor without a coating film has intrinsically good reproducibility and stability, it is an effective sensor for identifying and controlling the taste samples