Study on micropillar arrangement optimization of wireless-electrodeless quartz crystal microbalance sensor and application to a gas sensor

Self Cite

The hydrogen energy, which is environmentally friendly and does not emit carbon dioxide, has been attracting attention as an alternative fuel to the fossil fuel. In the shift to a hydrogen energy society, the highly sensitive hydrogen gas sensor has been required for the storage and management of hydrogen gas. In this research, we propose a film deposition method to induce the in-plane plastic deformation in the thin film, and apply it to a hydrogen gas sensor, where the palladium film formed by this method is deposited on a thin quartz resonator. It is found that the sensor chip with the plastically deformed palladium film is about 1.5 times more sensitive than the conventional sensor chip and has high-speed response. The developed sensor is a novel device that can be used in an oxygen-free environment without any temperature compensation and constant heating.

Section: Hydrogen Detection Performance Of Wireless Qcm Hydrogen Gas ...mentioning

confidence: 99%

Improvement of hydrogen detection sensitivity of palladium film by in-plane compressive plastic deformation and application to hydrogen gas sensor

Kato

Ato

Ichikawa

et al. 2022

Self Cite

“…Furthermore, to avoid the negative effects of the electrodes on the sensitivity, there is a method of wireless excitation of the quartz crystal resonator using a coil. [11][12][13][14][15][16] For sensors embedded in the human body, a method has been proposed, in which a quartz crystal resonator is connected to a coil to be remotely excited. 17) A non-contact measurement of liquid concentration as a resonance frequency has been proposed, where a capacitance related to the liquid concentration and a quartz crystal resonator are utilized.…”

Section: Introductionmentioning

confidence: 99%

Non-contact bolt axial force measurement based on the deformation of bolt head using quartz crystal resonator and coils

Hasebe

Wada

Nakamura

2022

As a health monitoring tool of bolts in infrastructures, we propose a non-contact evaluation method for the axial force of a bolt. Deformation of the bolt head is measured as an electrical capacitance variation detected as a frequency shift of a simple circuit composed of a quartz crystal resonator and coils. The measurement was carried out via magnetic field coupling between the coil installed on the bolt head and another coil connected to the measurement instrument. Since the method requires no active electronic circuit or battery for the bolt, low cost and high durability can be expected. First, the circuit was analyzed and optimized using an equivalent circuit model. Then, the feasibility of the proposed method was experimentally studied using a prototype. It was demonstrated that the method enabled non-contact axial force estimation in which the dependence on the distance between the coils is sufficiently small for detecting bolt looseness.

“…We have developed a ball surface acoustic wave (SAW) sensor, [9][10][11] as an application of piezoelectric devices [12][13][14][15] such as a planar SAW sensor 16) and quartz crystal microbalances. 17,18) Using the ball SAW sensor as a detector, we developed a portable ball SAW GC. [19][20][21][22][23][24][25] The key features of the ball SAW GC are the multiple roundtrips of a SAW on a spherical crystal 10,11) and a metal micro-electromechanical-system (MEMS) column 25) coated with a stationary phase in a 3 m long microchannel formed by diffusion bonding of etched stainless-steel plates.…”

Section: Introductionmentioning

confidence: 99%

Development of ball surface acoustic wave gas chromatograph for environmental monitoring in spacecraft and its application on the ground

Iwaya

Akao

Yamanaka

et al. 2022

For on-site analysis of surface materials on the moon, planets, and small bodies and for the monitoring of air quality in crewed spacecraft, we have developed a portable gas chromatograph (GC) equipped with a ball surface acoustic wave (SAW) sensor. In this study, we fabricated a 10 cm cube GC that implements the forward flush method using two metal micro-electro-mechanical-system (MEMS) columns coated with different stationary phases in microchannels fabricated by wet etching and diffusion bonding of stainless-steel plates. Using this GC, we succeeded in analyzing 10 kinds of gas within 10 min. In addition, for the application of the ball SAW GC on the ground, we also developed a palm-sized GC with a single metal capillary column and used it in the analysis of the headspace gas of sake. We showed that the ratio of peak areas differed among odorants depending on the brand and brewing process of sake.