Shear Horizontal Surface Acoustic Wave Resonators for Ammonia Detection

Abstract: This Shear horizontal surface acoustic wave (SH-SAW) devices coated with L-glutamic acid hydrochloride have been fabricated and used as ammonia sensors in this work. The humidity effect on the ammonia sensors was also studied. The sensitivity of the ammonia sensor was 4.6 ppm/ppm and the frequency shift was negative at 50°C in dry air. As the humidity rose in the environment, the sensor exhibited a positively increasing frequency shift. It proved that the humidity in the environment interfered with the detection to ammonia. This work would focus on estimating the cross-sensitivity of the humidity interference. Key-Words: Shear horizontal surface acoustic wave, L-glutamic acid hydrochloride, Ammonia, Sensitivity