IEEJ Transactions on Sensors and Micromachines
Online ISSN : 1347-5525
Print ISSN : 1341-8939
ISSN-L : 1341-8939
Search
Advanced search
OR
Browse
Search
Volume 130, Issue 3
Displaying 1-11 of 11 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
Paper
  • Differential Platinum Thin Film Hydrogen Gas Sensor Fabricated by MEMS Techniques
    Daisuke Yamazaki, Toshitsugu Ueda
    2010 Volume 130 Issue 3 Pages 65-68
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.65
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    In this paper, thermo-resistive platinum (Pt) thin film sensor, which was produced using Micro Electro Mechanical Systems (MEMS) fabrication techniques, is proposed. The sensor design incorporated resistor elements that would facilitate the temperature-resistance characteristics and mechanisms of Pt based thin film thermo-resistors. Especially, this paper reports the characteristics of a new differential Pt thin film hydrogen gas sensor. The fabricated hydrogen sensor detected the concentration of hydrogen gas in the air from 2% to 10%. It was possible to achieve the correct the heat transfer with this new differential Pt thin film hydrogen gas sensor. The characteristics of sensor's output are higher than conventional ones that we developed.
    View full abstract
    Download PDF (877K)
  • Study on Operation Mechanisms of Semiconducting Thin-Film Gas Sensors by Hall-Effect Measurements
    Daizo Uemura, Kazuhiro Hara
    2010 Volume 130 Issue 3 Pages 69-74
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.69
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    Although Fe2O3-based thin-film gas sensors show considerable sensitivity to pollutant gases such as NOX or inflammable gases such as H2 and i-C4H10, the operation mechanism is not clear. In this study, the Hall effect of the sensing film is measured in an atmosphere containing NOX or an inflammable gas to clarify the sensing mechanism based on the change of the measured carrier density and Hall mobility in the presence of the gas. This study makes clear that the change of carrier concentration mainly determines the sensitivity while the change of Hall mobility does not contribute to the sensitivity. In addition the surface density of chemisorbed species is roughly estimated from the measurements. The Debye length is also estimated and discussed in relation with the sensing mechanism.
    View full abstract
    Download PDF (874K)
  • Semiconducting Thin-Film Sensors for Detection of Polluting Gases and Floating Particles
    Tatsuya Yokoyama, Kazuhiro Hara
    2010 Volume 130 Issue 3 Pages 75-79
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.75
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    A micro sensor for polluting gases and organic floating particles has been developed. The sensor is composed of two parts: a sensing element and a micro heater. Both parts are fabricated using thin-film technology, IC fabrication, and a micromachining technique. The sensing film has a double-layered structure; the first layer is a Fe2O3-based thin-film and the second layer is a SnO2-based thin-film. They are deposited by r.f. sputtering on a SiO2/Al2O3/SiO2 diaphragm formed on a Si substrate. A thin-film heater is also fabricated on a similar diaphragm on another Si substrate. The sensing element and the micro heater are placed in parallel at a distance of about 50μm. The sensor is sensitive to polluting gases such as NOX, exhaust gases, cigarette smoke, and organic floating particles such as pollen.
    View full abstract
    Download PDF (656K)
  • Development of High Reliability and High Accuracy Micro Airflow Sensor for Automobile
    Masahiro Matsumoto, Masamichi Yamada, Hiroshi Nakano, Rintarou Minamit ...
    2010 Volume 130 Issue 3 Pages 80-85
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.80
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    A new cyclone bypass is adopted to prevent collision of dusts and water splash to the sensing element. Poly silicon heater and temperature sensor are used to obtain corrosion resistance and acidity-proof of the sensing element. The signal conditioning LSI compensates sensor characteristic by calculate 3rd order polynomial expression. Micro airflow sensor for automobile with high accuracy of 2% and high reliability of 2% was achieved.
    View full abstract
    Download PDF (843K)
  • Dual Axis Light Sensor for Tracking Sun
    Miki Shibata, Toyokazu Tambo
    2010 Volume 130 Issue 3 Pages 86-91
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.86
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    We have developed convenient light sensors to control a platform of solar cell panel. Dual axis light sensor in the present paper has structure of 5 PD (photodiode) light sensor which is composed of 5 photodiodes attached on a frustum of pyramid(1). Light source can be captured in front of the sensor by rotating the X and Y axis as decreasing the output deviation between two pairs of outside photodiodes. We here report the mechanism of sun tacking using the dual axis 5 PD light sensor and the fundamental results performed in the dark room.
    View full abstract
    Download PDF (680K)
  • Antireflection Subwavelength Gratings at Near-Infrared Wavelengths Fabricated by Self-Organized Nanoparticles
    Yoshiaki Kanamori, Shuhei Haida, Kazuhiro Hane
    2010 Volume 130 Issue 3 Pages 92-96
    Published: March 01, 2010
    Released on J-STAGE: March 01, 2010
    DOIhttps://doi.org/10.1541/ieejsmas.130.92
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    We design subwavelength gratings (SWGs) in 1.55 μm wavelength range used for optical communication devices or solar cells. Also, we propose a novel fabrication technique of SWGs using self-organized nanoparticles, for the large-area and low-cost fabrication. In the fabrication, SiO2 particles with the diameters of 170 nm are spin-coated on a silicon substrate. Then, a 170-nm-period SiO2 particle pattern is formed on the substrate. Using the SiO2 particles as a mask, the silicon substrate is etched by a dry etching machine. A 170-nm-period SWG with tapered profile is fabricated. The SWG height is approximately 820 nm. Reflectivity of the SWG is decreased to be -18.7 dB (1.3%) from -3.39 dB (45.8%) of a Si mirror surface at a wavelength of 1550 nm. Calculated reflectivity of the SWG at a wavelength of 1550 nm is -18.3 dB (1.5%), which almost agrees with the measured value.
    View full abstract
    Download PDF (1302K)
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top