S&M2752 Research Paper of Special Issue
Published in advance: March 4, 2021
Published: December 16, 2021
Fabrication of Impedance Sensor with Hydrophilic Property to Monitor Soil Water Content for Slope Failure Prognostics [PDF]
Masato Futagawa, Tatsumi Ito, Shin Ogasahara, Kenichiro Kusano, Yasushi Fuwa, and Mitsuru Komatsu
(Received November 1, 2020; Accepted February 19, 2021)
Keywords: soil water content, impedance sensor, LSI technology, hydrophilic property, slope failure prognostics
To minimize the damage caused by slope failure, knowledge of the increase in water content in mountain soil is important. Our group has been studying miniaturized impedance sensors for multipoint measurements in soil. Conventional sensors with a SiNx top film sometimes cannot detect changes in the water content in soil resulting from rain. Experiments on the slide distances of water droplets were performed using SiOx and SiNx films. As the slide distance of the SiOx film was shorter than that of the SiNx film, it was confirmed that the SiOx film is more hydrophilic than the SiNx film. To improve contact characteristics between the sensor surface and free water in soil, we covered our conventional sensor chip with a hydrophilic SiOx film. As a contact property test, the sensor chip measured the impedances of model soils. The proposed sensor achieved stable contact with the free water in the soil. Moreover, the chip operated for a long period of time on a mountain slope. The sensor could measure nearly theoretical outputs in response to rainfall. Thus, we succeeded in fabricating a stable soil monitor sensor with a hydrophilic SiOx film.Corresponding author: Masato Futagawa
This work is licensed under a Creative Commons Attribution 4.0 International License.
Cite this article
Masato Futagawa, Tatsumi Ito, Shin Ogasahara, Kenichiro Kusano, Yasushi Fuwa, and Mitsuru Komatsu, Fabrication of Impedance Sensor with Hydrophilic Property to Monitor Soil Water Content for Slope Failure Prognostics, Sens. Mater., Vol. 33, No. 12, 2021, p. 4147-4156.