| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensor high in detection accuracy easy to produce and utilizing various parameters possessed by a surface elastic wave device. SOLUTION: In a resonator type surface elastic wave filter equipped with an IDT electrode 1 (A1), a reflector 2 and a piezoelectric substrate (quartz ST cut plate), the whole of the surface containing the IDT electrode 1 and the reflector 2 of the filter is coated with TiO2 (film thickness; about 1μm) by using a spin coating method. This surface elastic wave filter is set to a container capable of being evacuated and susceptible to gas substitution. After the container having the surface elastic wave filter housed therein is evacuated, the interior of the container is set to an air atmosphere containing a sample to be irradiated with ultraviolet rays and, immediately after irradiation, a change of the center frequency, insertion loss and impedance (resistsance + reactance) of the surface elastic wave filter is measured. The chemical seed of the sample is identified from the measured result. Further, the photocatalyst reaction possessed by TiO2 is monitored by the measurement of impedance. |
