Strain Sensitizing of High-Sensitivity SAW Sensor Based on FBG

Author(s):  
Zhang Wei
Keyword(s):  
2014 ◽  
Vol 28 (07) ◽  
pp. 1450056 ◽  
Author(s):  
Hua-Lin Cai ◽  
Yi Yang ◽  
Yi-Han Zhang ◽  
Chang-Jian Zhou ◽  
Cang-Ran Guo ◽  
...  

In this paper, a surface acoustic wave (SAW) biosensor with gold delay area on LiNbO 3 substrate detecting DNA sequences is proposed. By well-designed device parameters of the SAW sensor, it achieves a high performance for highly sensitive detection of target DNA. In addition, an effective biological treatment method for DNA immobilization and abundant experimental verification of the sensing effect have made it a reliable device in DNA detection. The loading mass of the probe and target DNA sequences is obtained from the frequency shifts, which are big enough in this work due to an effective biological treatment. The experimental results show that the biosensor has a high sensitivity of 1.2 pg/ml/Hz and high selectivity characteristic is also verified by the few responses of other substances. In combination with wireless transceiver, we develop a wireless receiving and processing system that can directly display the detection results.


ACS Sensors ◽  
2016 ◽  
Vol 2 (1) ◽  
pp. 157-164 ◽  
Author(s):  
Pintu Adhikari ◽  
Laura Alderson ◽  
Florian Bender ◽  
Antonio J. Ricco ◽  
Fabien Josse

2012 ◽  
Vol 22 (2) ◽  
pp. 025002 ◽  
Author(s):  
Haekwan Oh ◽  
Keekeun Lee ◽  
Kyoungtae Eun ◽  
Sung-Hoon Choa ◽  
Sang Sik Yang

2021 ◽  
Vol 11 (17) ◽  
pp. 8123
Author(s):  
Yahui Tian ◽  
Honglang Li ◽  
Wencan Chen ◽  
Zixiao Lu ◽  
Wei Luo ◽  
...  

Surface acoustic wave (SAW) sensors have been applied in various areas with many advantages, such as their small size, high sensitivity and wireless and passive form. Love wave mode sensors, an important kind of SAW sensor, are mostly used in biology and chemistry monitoring, as they can be used in a liquid environment. Common Love wave mode sensors consist of a delay line with waveguide and sensitive layers. To extend the application of Love wave mode sensors, this article reports a novel Love wave mode sensor consisting of a waveguide layer with microphononic crystals (PnCs). To analyze the properties of the new structure, the band structure was calculated, and transmission was obtained by introducing delay line structures and quasi-three-dimensional models. Furthermore, devices with a traditional structure and novel structure were fabricated. The results show that, by introducing the designed microstructure of phononic crystals in the waveguide layer, the attenuation was barely increased, and the frequency was shifted by a small amount. In the liquid environmental experiments, the novel structure with micro PnCs shows even better character than the traditional one. Moreover, the introduced microstructure can be extended to microreaction tanks for microcontrol. Therefore, this novel Love wave mode sensor is a promising application for combining acoustic sensors and microfluidics.


2021 ◽  
Vol 22 (2) ◽  
pp. 168-177
Author(s):  
Aliza Aini Md Ralib ◽  
Amirah Syahirah Syamsil Omar

Surface acoustic wave sensors (SAWs) are excellent at detecting volatile organic compounds (VOCs) since a sensing layer can be created by spreading a thin film of material across the delay line. This critically enhances performance as it is sensitive to the physical phenomena of interest. This study aims to provide a thorough investigation of the sensitivity of polymer-coated SAW-based gas sensors to VOCs using simulations via the finite element method (FEM). As such, quartz was chosen as the piezoelectric substrate while polymeric materials were chosen as the sensing layers due to their high sensitivity, low energy consumption, short response time, performance at room temperature, and reversibility after exposure to an analyte. The polymeric materials chosen were: (1) polyisobutylene (PIB), (2) polydimethylsiloxane (PDMS), (3) polyisoprene (PIP), (4) polyimide (PI), and (5) phenylmethyldiphenylsilicone (OV25). The VOCs chosen for investigation were: (1) dichloromethane (DCM), (2) trichloroethylene (TCE), (3) 1,2-dichloroethylene (DCE), and (4) carbon tetrachloride (CCl4). The performance of each polymer-coated SAW sensor was evaluated in terms of frequency shift and sensitivity to each VOC in FEM simulations. Our study found that the PIB-coated sensor had the highest sensitivity (4.0571 kHz/ppm) to DCM vapor and good sensitivity (45.257 kHz/ppm) to TCE vapor. However, the performance of each polymer-coated sensor varied depending on the type of VOC being tested. As an example, while the OV25-coated sensor was more sensitive (52.57 kHz/ppm) than the PIB-coated sensor (53.54 kHz/ppm) to TCE vapor regardless of the concentration, the PIB-coated sensor was more sensitive to DCM vapor at both low (4.06 kHz/ppm) and high (3.54 kHz/ppm) concentrations than the OV25-coated sensor. Therefore, the results of our FEM simulations indicate that polymer-coated SAW-based gas sensors are highly capable of self-powered VOC detection. ABSTRAK: Sensor gelombang akustik permukaan (SAW) adalah sangat baik dalam mengesan sebatian organik meruap yang tidak stabil (VOCs), kerana lapisan pengesan dapat dihasilkan dengan melapis nipis bahan pada lapisan garis tunda. Cara ini dapat menambah baik prestasi kerana ianya sensitif kepada fenomena fizikal yang dituju. Kajian ini bertujuan bagi menyediakan kajian menyeluruh terhadap kesensitifan sensor gas berasaskan SAW bersalut polimer pada VOC menggunakan simulasi melalui kaedah unsur terhingga (FEM). Oleh itu, kuarza dipilih sebagai substrat piezoelektrik manakala bahan polimer dipilih sebagai lapisan penginderaan berdasarkan kepekaan tinggi, penggunaan tenaga rendah, respon masa singkat, prestasi suhu bilik, dan faktor keboleh-balikan setelah terdedah kepada analit. Bahan polimer yang dipilih adalah: (1) polisobutilena (PIB), (2) polidimethilsiloxana (PDMS), (3) polisoprena (PIP), (4) polimida (PI), dan (5) phenilmethildiphenilsilikon (OV25). VOC terpilih bagi kajian adalah: (1) diklorometana (DCM), (2) trikloretilena (TCE), (3) 1,2-dikloroetilena (DCE), dan (4) karbon tetraklorida (CCl4). Prestasi setiap sensor SAW bersalut polimer dinilai berdasarkan peralihan frekuensi dan kesensitifan pada setiap VOC simulasi FEM. Dapatan kajian menunjukkan sensor bersalut-PIB mempunyai kesensitifan paling tinggi (4.0571 kHz/ppm) terhadap wap DCM dan kepekaan yang baik (45.257 kHz / ppm) terhadap wap TCE. Walau bagaimanapun, prestasi setiap sensor bersalut polimer adalah berbeza bergantung kepada jenis VOC yang sedang diuji. Sebagai contoh, sensor bersalut OV25 adalah lebih sensitif (52,57 kHz/ppm) daripada sensor bersalut PIB (53,54 kHz/ppm) pada wap TCE tanpa mengira kepekatan. Manakala sensor bersalut PIB lebih sensitif terhadap wap DCM pada kedua-dua kepekatan rendah (4.06 kHz/ppm) dan tinggi (3.54 kHz/ppm) daripada sensor bersalut-OV25. Oleh itu, hasil simulasi FEM menunjukkan bahawa sensor gas berasaskan SAW bersalut polimer adalah sangat berpotensi sebagai pengesan VOC berkuasa sendiri.


2013 ◽  
Vol 664 ◽  
pp. 986-989 ◽  
Author(s):  
Zhi Hua Ying ◽  
Jia Hu ◽  
Cong Ping Wu ◽  
Yi Qing Yang ◽  
Liang Zheng ◽  
...  

This study contributes to the measurements of formaldehyde at room temperature. A bilayer structure based surface acoustic wave (SAW) sensor has been fabricated and experimentally studied. The coating materials carbon nanotubes (CNTs) and poly (4-vinylphenol) (P4VP) were deposited by a spray-painting method onto SAW sensors configured as 433.92MHz two-port resonator-based oscillators. The results display high sensitivity and entirely reversibility. The response and recovery times of the bilayer structure are very short, and the response values are obviously greater than plus of the two single layers. Some sensing mechanisms between analytes and the bilayer structure SAW sensor will be discussed preliminarily.


1994 ◽  
Vol 144 ◽  
pp. 21-28 ◽  
Author(s):  
G. B. Gelfreikh

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.


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