scholarly journals Characteristics of Highly Sensitive Hydrogen Sensor Based on Pt-WO3/Si Microring Resonator

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 96 ◽  
Author(s):  
Sosuke Matsuura ◽  
Naoki Yamasaku ◽  
Yoshiaki Nishijima ◽  
Shinji Okazaki ◽  
Taro Arakawa
Keyword(s):  
Sol Gel ◽  
Tungsten Bronze ◽  
Complementary Metal Oxide Semiconductor ◽  
Hydrogen Sensor ◽  
Hydrogen Gas ◽  
Microring Resonator ◽  
Oxide Semiconductor ◽  
Gas Sensitivity ◽  
Highly Sensitive ◽  
New Energy

Hydrogen gas has attracted attention as a new energy carrier, and simple but highly sensitive hydrogen sensors are required. We fabricated an optical hydrogen sensor based on a silicon microring resonator (MRR) with tungsten oxide (WO3) using a complementary metal-oxide-semiconductor (CMOS)-compatible process for the MRR and a sol-gel method for the WO3 layer and investigated its sensing characteristics at device temperatures of 5, 20, and 30 °C. At each temperature, a hydrogen concentration of as low as 0.1 vol% was successfully detected. The gas sensitivity increased with decreasing temperature. The dependence of the sensitivity on the device temperature can be attributed to the thickness of tungsten bronze (HxWO3) formed by WO3 during exposure to hydrogen gas. In addition, a hydrogen gas sensor based on a silicon-MRR-enhanced Mach–Zehnder interferometer (MRR-MZI) is proposed and its significantly high sensing ability using improved changes in the transmittance of light is theoretically discussed.

scholarly journals Response Characteristics of Silicon Microring Resonator Hydrogen Sensor

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 795
Author(s):  
Naoki Yamasaku ◽  
Sosuke Matsuura ◽  
Yoshiaki Nishijima ◽  
Taro Arakawa ◽  
Shinji Okazaki
Keyword(s):  
Sol Gel ◽  
Hydrogen Sensor ◽  
Hydrogen Gas ◽  
Microring Resonator ◽  
Wavelength Shift ◽  
Pure Hydrogen ◽  
Sensitive Layer ◽  
Response Characteristics ◽  
Gel Technique ◽  
Resonant Wavelength Shift

A silicon microring-resonator (MRR) hydrogen sensor which utilizes platinum-loaded tungsten oxide (Pt/WO3) thin film was fabricated and evaluated. The uniform film was deposited on MRR portion by using sol-gel technique. By the exposure to pure hydrogen gas, the sensor devise showed the large resonant wavelength shift at room temperature. It is suggested that the change in the optical properties of hydrogen sensitive layer results in this response.

Ethanol Sensor Based on Microring Resonator

2013 ◽  
Vol 655-657 ◽  
pp. 669-672
Author(s):  
Yao Chen ◽  
Yu Li Ding ◽  
Zheng Yu Li
Keyword(s):  
Chemical Sensors ◽  
Environmental Control ◽  
Low Cost ◽  
Virus Detection ◽  
Complementary Metal Oxide Semiconductor ◽  
Medical Diagnostics ◽  
Ethanol Solution ◽  
Microring Resonator ◽  
Oxide Semiconductor ◽  
Detection Mechanism

Chemical sensors is gaining long-standing interests due to their applications in many areas such as bacterial and virus detection, medical diagnostics, drug development, food safety and environmental control. Among the existing chemical sensors, optical planar sensors show promising and attempt to beat their commercialized competitors because of their robustness, lable-free detection mechanism, mature complementary metal oxide semiconductor (coms) fabrication technology and naturally low cost. Silicon nitride microring resonators were demonstrated as chemical sensors. Using the technique of coms technology, the microring devices were fabricated with 200 µm in radius. Performance of the devices was measured, which showed the quality factor (q) was up to 25,000. Sensitivity of 108.9336 nm per reflective index unit (nm/riu) and detection limit of 1.836×10-4 riu were demonstrated by using various concentrations of ethanol solution as analytes.

scholarly journals Terahertz real-time imaging uncooled array based on antenna- and cavity-coupled bolometers

2014 ◽  
Vol 372 (2012) ◽  
pp. 20130111 ◽  
Author(s):  
François Simoens ◽  
Jérôme Meilhan
Keyword(s):  
Real Time ◽  
Direct Detection ◽  
Detection Threshold ◽  
Complementary Metal Oxide Semiconductor ◽  
Industrial Applications ◽  
Oxide Semiconductor ◽  
Thz Radiation ◽  
Quarter Wavelength ◽  
Highly Sensitive ◽  
Thz Range

The development of terahertz (THz) applications is slowed down by the availability of affordable, easy-to-use and highly sensitive detectors. CEA-Leti took up this challenge by tailoring the mature infrared (IR) bolometer technology for optimized THz sensing. The key feature of these detectors relies on the separation between electromagnetic absorption and the thermometer. For each pixel, specific structures of antennas and a resonant quarter-wavelength cavity couple efficiently the THz radiation on a broadband range, while a central silicon microbridge bolometer resistance is read out by a complementary metal oxide semiconductor circuit. 320×240 pixel arrays have been designed and manufactured: a better than 30 pW power direct detection threshold per pixel has been demonstrated in the 2–4 THz range. Such performance is expected on the whole THz range by proper tailoring of the antennas while keeping the technological stack largely unchanged. This paper gives an overview of the developed bolometer-based technology. First, it describes the technology and reports the latest performance characterizations. Then imaging demonstrations are presented, such as real-time reflectance imaging of a large surface of hidden objects and THz time-domain spectroscopy beam two-dimensional profiling. Finally, perspectives of camera integration for scientific and industrial applications are discussed.

Room Temperature Hydrogen Gas Sensitivity of Nanocrystalline-Doped Tin Oxide Sensor Incorporated into MEMS Device

2004 ◽  
Vol 828 ◽  
Author(s):  
Satyajit Shukla ◽  
Rajnikant Agrawal ◽  
Lawrence Ludwig ◽  
Hyoung Cho ◽  
Sudipta Seal
Keyword(s):  
Tin Oxide ◽  
Room Temperature ◽  
Microelectromechanical Systems ◽  
Sol Gel ◽  
High Sensitivity ◽  
Hydrogen Gas ◽  
Chamber Pressure ◽  
Gas Sensitivity ◽  
Film Sensor ◽  
Mems Device

ABSTRACTNanocrystalline indium oxide (In2O3)-doped tin oxide (SnO2) thin film sensor has been sol-gel dip-coated on a microelectromechanical systems (MEMS) device. The micro-sensor device is successfully utilized to sense ppm level H2 at room temperature with high sensitivity. The chamber pressure has no pronounce effect on the room temperature H2 sensitivity.

Hydrogen-Sensor Prepared Using Proton-Conducting Glass Films

2007 ◽  
Vol 124-126 ◽  
pp. 627-630 ◽  
Author(s):  
Midori Matsumura ◽  
Yusuke Daiko ◽  
Masayuki Nogami
Keyword(s):  
Thin Film ◽  
Indium Tin Oxide ◽  
High Speed ◽  
Sol Gel ◽  
Reference Electrode ◽  
Hydrogen Sensor ◽  
Hydrogen Gas ◽  
Oxide Thin Film ◽  
Proton Conducting ◽  
Glass Films

Solid-state potentiometric thin film hydrogen gas sensors were successfully fabricated using a sol-gel-derived high proton-conducting P2O5-SiO2 glass films. Manganese oxide thin film coated on an indium tin oxide (ITO)-coated glass substrate was used for reference electrode. The sensor exhibited high speed responsibility within 10 s and 120 s at 30 oC and -30oC, respectively, for 1 vol.% hydrogen gas. A linear relationship between the electromotive force (EMF) and the logarithmic hydrogen concentration of 0.1~1 vol.% was obtained in the temperature ranging from -30 to 30 oC. The sensing mechanism was also discussed to improve the sensitivity and sensing speed against low H2 concentration at low temperatures.

scholarly journals Palladium nanoparticle-decorated multi-layer Ti3C2Tx dual-functioning as a highly sensitive hydrogen gas sensor and hydrogen storage

RSC Advances ◽  
2021 ◽  
Vol 11 (13) ◽  
pp. 7492-7501
Author(s):  
Thanh Hoang Phuong Doan ◽  
Won G. Hong ◽  
Jin-Seo Noh
Keyword(s):  
Hydrogen Storage ◽  
Gas Sensor ◽  
Hydrogen Sensor ◽  
Hydrogen Gas ◽  
Dual Function ◽  
Palladium Nanoparticle ◽  
Step Process ◽  
Highly Sensitive

Nanocomposites of PdNPs and ML-Ti3C2Tx MXene are synthesized using a facile two-step process, and it is demonstrated that they can dual-function as a highly sensitive hydrogen sensor and hydrogen storage.

An Improved Thermal Type Microsensor with Thermal Isolation Microcracks

2010 ◽  
Vol 97-101 ◽  
pp. 4230-4233
Author(s):  
Yun Zi Cai ◽  
Chih Hsiung Shen ◽  
Shu Jung Chen
Keyword(s):  
Heat Flow ◽  
High Performance ◽  
Infrared Detector ◽  
Thermal Conductance ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Main Stream ◽  
Infrared Sensors ◽  
Ir Radiation ◽  
Highly Sensitive

A new idea of improving complementary metal-oxide-semiconductor (CMOS) thermopile performance is introduced to reduce the thermal conductance by leading the microcracks into structure of thermopile, which greatly increases the heat flow barrier. A highly sensitive infrared detector requires a low thermal conductance to maximize the temperature change and signal induced by incident IR radiation. Several designs of infrared microsensors are proposed to study influential parameters from microcrack for improving performance of thermopile. To that end, by using some adequate designs of polysilicon architecture, we can greatly reduce the heat flow from the main stream without introducing further electric resistance, which is related with noise. Firstly we develop such a structure of thermopile with low thermal conductance and high performance by using CMOS compatible process which can be easily and exactly fabricated. The suspended structure of infrared sensors is used in this study to provide ideal, thermally isolated, structures for support of the thin film detector. We also simulate the heat flow of the new structures. The results show good match with our original idea.

A Capacitive Ammonia Sensor Using the Commercial 0.18 μm CMOS Process

2015 ◽  
Vol 1091 ◽  
pp. 3-8
Author(s):  
Ming Zhi Yang ◽  
Ching Liang Dai
Keyword(s):  
Sol Gel ◽  
Complementary Metal Oxide Semiconductor ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Ammonia Vapor ◽  
Ammonia Sensor ◽  
Post Process ◽  
Sensitive Film ◽  
Interdigital Electrodes

The project presents an ammonia sensor with heater on-a-chip manufactured using the commercial 0.18 μm CMOS (complementary metal oxide semiconductor) process. The ammonia sensor is composed of a sensitive film, interdigital electrodes and a polysilicon heater. The sensor is a capacitive type and the sensitive film is ZrO2that is prepared by sol-gel method. The sensor requires a post-process to remove the sacrificial oxide layer and coat the ZrO2film on the interdigital electrodes. When the sensitive film absorbs ammonia vapor, the capacitance of the sensor generates a change. Experimental results show that the sensitivity of the ammonia sensor is 2.47 pF/ppm at 270 °C.

Preparation and Characterization of Pt/WO3 Nano-Film and Its Hydrogen-Sensing Properties

2008 ◽  
Author(s):  
Changjun Hou ◽  
Jiale Dong ◽  
Yan Xu ◽  
Danqun Huo ◽  
Yike Tang ◽  
...  
Keyword(s):  
Tungsten Trioxide ◽  
Gas Sensing ◽  
Sol Gel ◽  
Hydrogen Gas ◽  
Molecular Structures ◽  
Oxide Semiconductor ◽  
Pt Catalyst ◽  
Hydrogen Sensing ◽  
Afm Analysis ◽  
Type Semiconductor

Tungsten trioxide is an n-type semiconductor, which has been extensively used for the development of metal oxide semiconductor gas sensors. The hydrogen gas sensing performance of platinum (Pt) catalyst activated WO3 thin films were investigated here. All of the Pt/WO3 films membranes are sensitive to hydrogen gas and the sample by sol-gel and DC reactive magnetron sputtering methods. X-ray diffraction results indicate that the tungsten trioxide is cubic crystal, and the AFM analysis shows molecular structures of the samples are tetrahedron. It means the four consecutive quadrilateral forms we observed in the 9nmx9nm molecular structure are scattergram of tungsten-ions and oxide-ions on 106 sides in WO2.9 structure cell, and the lost one oxide-ion resulted in the transition of WO3 to WO2.9. With anneal temperature rising, the membranous poriness decreasing. The higher crystal degree is, the lower gasochromic efficiency is. The change of combining environment and content of O−2 ions in colorized / decolorized state WOx films was observed in XPS analysis of Pt/WO3 film, the peak shape had changed greatly. As a result, the explanation to this phenomenon is available here according to XPS chemical shift of electric potential model theory.

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