The interference of humidity on a shear horizontal surface acoustic wave ammonia sensor

The interference of humidity on an ammonia sensor was studied in this work. The shear horizontal surface acoustic wave (SH-SAW) device coated with L-glutamic acid hydrochloride was fabricated and used as an ammonia sensor. The sensitivity of the SH-SAW ammonia sensor was 4.6 ppm/ppm and the mass loading dominated the perturbation in dry air at 50 degrees C. As the humidity rose in the environment, the perturbation was primarily from the elastic effect. This work estimated the cross-sensitivity of the interference of humidity. Finally, the neural network technique was used to identify ammonia in the environment. (c) 2006 Elsevier B.V. All rights reserved.