SURFACE-ACOUSTIC-WAVE MICROSENSORS

It was found that a surface acoustic wave microsensor is highly sensit ive in detecting the physical and chemical changes of the medium on th e vibrating surface in real time. Hence, microsensors are used in many applications. There are already several types of surface acoustic wav e microsensors with their differences based on vibration and wave mode s. New types of sensors are proposed herein and new findings and new a pplications are reported. The present level of development of surface acoustic wave microsensors is described and these sensors are compared , discussed, and evaluated. Fundamental characteristics are then prese nted for the shear-surface acoustic wave (SH-SAW) microsensors using a 36 degrees rotated Y-plate X-propagation LiTaO3 studied by the author s. It is shown that this sensor has many applications. Further, if sev eral SH-SAW sensors with different frequencies are used, a high recogn ition rate can be obtained even for liquid samples that cannot be reco gnized by human perception. The example used here is 13 types of whisk ey.