Comparison of Acoustic Wave Sensors With Different Cut src='/images/tex/18822.gif' alt='{rm LiNbO}_{3}'> Working on Pseudo-LFE Mode

摘要

In this paper, two pseudo-LFE devices made up of X-cut and (yxl) 21.82$^{circ}~{rm LiNbO}_{3}$ are investigated and compared. The coupling factors of both devices are calculated and the impedance characteristics are tested by impedance analyzer. The sensitivity and stability of both devices to the electrical property changes of liquid are also tested in isopropanol-water and NaCl-water solution. We find that the X-cut ${rm LiNbO}_{3}$ device has a higher piezoelectric coupling factor and better resonance in the deionized water than (yxl) 21.82$^{circ}~{rm LiNbO}_{3}$ device. The results also show that X-cut ${rm LiNbO}_{3}$ devices are more sensitive to the change of liquid conductivity and permittivity than (yxl) 21.82$^{circ}~{rm LiNbO}_{3}$ device even with similar stability.